WO2011069121A1

WO2011069121A1 - Mesenchymal stem cells (mscs) isolated from mobilized peripheral blood

Info

Publication number: WO2011069121A1
Application number: PCT/US2010/058980
Authority: WO
Inventors: Wayne Marasco; Satish Medicetty; Yajuan Jiang
Original assignee: Neostem, Inc.
Priority date: 2009-12-04
Filing date: 2010-12-03
Publication date: 2011-06-09
Also published as: TW201130977A

Abstract

The present invention generally relates to methods of obtaining peripheral blood-derived MSCs (PB- derived MSCs) and bone-marrow derived MSC (BM-derived MSCs) from a peripheral blood sample obtained from a human subject. In particular, the present invention relates to the surprising discovery that the mobilization of MSC into the peripheral blood is temporally regulated and that the number of circulating MSCs in human peripheral blood peaks after at least 2 days post administration of a mobilizing agent, such as G-CSF or GM-CSF to a human subject. Accordingly, in some embodiments, the present invention relates to methods of obtaining PB-derived and BM-derived MSC from peripheral blood from a human subject in vivo and ex vivo using mobilizing agents, such as G-CSF or GM-CSF, where administration of G-CSF and/or GM-CSF are optimized to mobilize MSCs and enrich the number of MSCs in the peripheral blood as apposed to other stem cell populations, such as HSCs.

Description

MESENCHYMAL STEM CELLS (MSCs) ISOLATED FROM MOBILIZED PERIPHERAL

BLOOD

FIELD OF THE INVENTION

[001] The present invention relates to the stem cells, in particular methods and compositions for the optimal timing for the isolation of human mesenchymal stem cells (MSCs) from mobilized peripheral blood, and subsequent use of isolated MSCs, such as cryopreservation and/or for the treatment of a subject in need thereof, such as in autologous regenerative medicine.

BACKGROUND OF THE INVENTION

[002] Mesenchymal stem cells (MSCs) are multi-potent cells which have great utility in the field of cell therapy. MSCs can differentiate into at least three downstream mesenchymal cell lineages (i.e., osteoblasts, chondroblasts and adipocytes). To date, no unique MSC marker has been identified. As such, morphological and functional criteria are used to identify these cells. See, Horwitz E, et al., "Clarification of the nomenclature for MSC: the international Society for Cellular Therapy position statement," Cytotherapy 7:393 (2005); and Dominici M, et al., "Minimal criteria for defining multipotent mesenchymal stromal cells. The international Society for Cellular Therapy position statement," Cytotherapy 8:315 (2006). Because MSCs can differentiate into many cell types, the art contemplates methods for differentiating MSCs for cell-based therapies, for regenerative medicine and for reconstructive medicine.

[003] For the preparation of MSCs compositions, the typical process consists of isolating the MSCs based on their plastic-adherence properties and thereafter expanding them in culture. This process is relatively easy when the MSCs are isolated from human body fluids during fetal development. However, obtaining MSCs from adult body fluids is much more complicated and less reproducible.

[004] Typically, MSCs are isolated from adult bone marrow, fat, cartilage and muscle. Pittenger F, et al., "Multilineage potential of adult human mesenchymal stem cells," Science 284: 143-147 (1999); Zuk P, et al., "Multilineage cells from human adipose tissue: implications for cell-based therapies," Tissue Eng. 7:21 1-228 (2001); and Young H, et al., "Human reserve pluripotent mesenchymal stem cells are present in the connective tissues of skeletal muscle and dermis derived from fetal, adult, and geriatric donors," Anat. Rec. 264:51-62 (2001).

[005] MSCs can also be isolated from human neonatal tissue, such as Wharton's jelly (Wang H, et al., "Mesenchymal stem cells in the Wharton's jelly of the human umbilical cord," Stem Cells 22: 1330-1337 (2004)), human placenta (Fukuchi Y, et al., "Human placenta-derived cells have mesenchymal stem/progenitor cell potential," Stem Cells 22:649-658 (2004)); and umbilical cord blood (Erices A, et al., "Mesenchymal progenitor cells in human umbilical cord blood," Br. J. Haematol. 109:235-242 (2000)) and human fetal tissues (Campagnoli C, et al., "Identification of mesenchymal stem/progenitor cells in human first-trimester fetal blood, liver, and bone marrow," Blood 98:2396-2402 (2001)).

[006] The art is limited by an inability to isolate sufficient MSCs for subsequent differentiation and use. Where suitable donors are available, the invasive procedures, such as bone marrow biopsy which are required to isolate even a limited number of MSCs present significant risks to donors. It also remains difficult to maintain isolated MSCs in long-term culture and to maintain such cultures free of bacterial or viral contamination.

[007] It has been previously reported that MSCs can be isolated from human non-mobilized peripheral blood. Kassis I, et al, report the "Isolation of mesenchymal stem cells from G-CSF- mobilized human peripheral blood using fibrin microbeads," Bone Marrow Transplant. 37:967-976 (2006). Kassis I, et al report that MSCs be obtained from mobilized peripheral blood and to a lesser extent from non-mobilized peripheral blood. Mobilization of MSCs to peripheral blood has been reported by administration of Granulocyte-colony Stimuling Factor (G-CSF) for a period of at least 5 days. However, this method appears to be defective and poorly reproducible because only a small percentage of MSCs are isolated, and these have limitations in their growth and expansion potential.

[008] Therefore, it is necessary to find an improved method for obtaining MSCs from peripheral blood, which allows the preparation of enriched MSCs populations.

[009] Citation of the above documents is not intended as an admission that any of the foregoing is pertinent prior art. All statements as to the date or representation as to the contents of these documents is based on the information available to the applicants and does not constitute and admission as to the correctness of the dates or contents of these documents.

SUMMARY OF THE INVENTION

[0010] The present invention generally relates to the discovery of the administration of a mobilizing agent and the optimal timing of collecting a particular stem cell population from mobilized peripheral blood. In particular, the inventors have discovered the optimal timing of collecting and isolating mesenchymal stem cells (MSCs) from mobilized peripheral blood following

administration of a mobilizing agent, such as for example but not limited to, GM-CSF and G-CSF, or AM3100 (Plerixafor). Stated another way, the inventors have surprisingly discovered a method of achieving a superior yield of MSCs by isolating the mobilized MSC at an optimal timepoint following administration of a mobilizing agent when they are at their maximum levels in the mobilized peripheral blood.

[0011] The inventors have surprisingly discovered that the mobilization of MSC into the peripheral blood is temporally regulated and that the number of circulating MSCs in human peripheral blood peaks at a different time than other mobilized stem cell populations such as HSCs following the administration of a mobilizing agent, such as G-CSF or GM-CSF to a human subject. Accordingly, the inventors have demonstrated that the protocol of the use of G-CSF or GM-CSF to optimize the mobilization of MSCs into the peripheral blood is different from that typically used for

mobilization of other stem cells, such as CD34+ HSCs into the peripheral blood.

[0012] Accordingly, the present invention relates to the discovery that different stem cell populations are mobilized from bone marrow in a temporally regulated manner. In particular, the inventors have discovered that different stem cell populations are released or produced by the bone marrow at different times following administration of specific stem cell mobilizing agents, and

consequently, the timing of collection or isolation of a certain population of stem cells from mobilized peripheral blood needs to be coordinated in order to optimize the isolation of a specific stem cell population of interest. For example, the inventors have discovered that administration of a stem cell mobilizing agent to a subject will mobilize stem cells at different rates, for different durations and at different amounts at different times, and therefore the inventors have discovered that the stem cell of interest to be harvested from mobilized peripheral blood will dictate a coordinated dosing regimen and harvesting of the stem cells from the mobilized peripheral blood. For example, the inventors have discovered that a peripheral blood mobilizing factor, such as GM- CSF and/or G-CSF mobilizes different stem cell populations such as hematopoietic stem cells (HSCs), Mesenchymal stem cells (MSCs) and other stem cell populations, such as very small embryonic like (VSEL) stem cells ("VSELs") into the peripheral blood in distinct temporal pattern.

[0013] Surprisingly, unlike the conventional use of GM-CSF and/or G-CSF which is administered for at least 5 days and HSCs being collected on the 6th day, the inventors have unexpectedly discovered that high concentration of MSCs in mobilized blood can be achieved after about 2 days of administration of GM-CSF and/or G-CSF. Thus, the inventors have discovered a method to obtain an optimal yield of MSCs, whereby the MSCs are collected or isolated from mobilized peripheral blood following administration of such a mobilizing agent for at least 1 day, but no more than 4 days. In one embodiment, such a mobilizing agent is administered about 2 days, and the MSC harvested on the last day of administration of the mobilizing agent or on the next day. There are other mobilizing agents that have different temporal responses, and they can be used to mobilize MSCs for at least 1 day and less than 4 days foll owing administration of the mobilizing agents.

[0014] Mobilization of stem cells by growth factors such as G-CSF or GM-CSF at conventional doses, (e.g. typically for 5 days at about 5- l(^g/kg/day is expensive, and has undesirable side effects including causing extensive bone pain, headaches, fatigue, potential spontaneous spleen rupturing and has unknown side effects for normal donors, including increased risk of

hematopoietic malignancy and myeloid leukemia (AML) (see Casheen et al., Bone Marrow^r Transplant, 2007, 39; 577-588). Additionally, the conventional mobilization protocols are unpredictable, result in a low yield, and can often take up to about 4 weeks of G-CSF or GM-CSF treatments to collect sufficient material for a transplant. After growth factor treatment, HSC CD34+ cells reach a maximum level of 2-4% in blood.

[0015] MSCs are typically obtained from bone marrow. It has been previously reported that MSCs are present in very low levels in peripheral blood and mobilized peripheral blood (see Wexler et al., British J. Haematology, 2003; 121 ; 368-374; "Adult Bone Marrow is a rich source of human mesenchymal "stem" cells but umbilical cord and mobilized adult blood are not"). Furthermore, reports have discussed that not all mobilized blood could yield MSCs (see Kassis et al., Bone Marrow Transplantation, 2006; 37; 967-976). Furthermore, even if MSCs are collected from non- mobilized peripheral blood they can not be collected in sufficient quantities for future autologous transplantation, even if expanded in culture, due to the nature of MSCs senesce, and limited number of passages before losing their multipotent potential. This, the present invention is related to the surprising discovery that, counter to the previous reports, MSCs can be obtained from mobilized peripheral blood in sufficient quantities for therapeutic use when the MSCs are obtained or harvested from the mobilized peripheral blood at an optimal time when they are at their highest yield in the circulation.

[0016] Another aspect of the present invention relates to the discovery that MSCs, as well as

migrating from the bone marrow to the peripheral blood in a process that is known as

"mobilization," also proliferate in the peripheral blood. Thus, mobilizing agents as disclosed herein, such as GM-CSF and G-CSF or agonists thereof can be (i) administered to a subject to enhance the mobilization of MSC from the bone marrow^r to the peripheral blood to increase the number of bone-marrow derived MSCs (herein referred to "BM-derived MSCs") in the peripheral blood, and/or (ii) peripheral blood from a subject can be contacted with mobilizing agents, such as GM-CSF and G-CSF ex vivo to mobilize and enhance proliferation of MSC in the peripheral blood to increase the number of peripheral-blood derived MSCs (herein referred to "PB-derived MSCs") in the peripheral blood. Additional mobi lization agents to be used in the practice of the invention include those selected from the group consisting of interleukin-17, AMD3100 , cyclophosphamide (Cy), Docetaxel and (DXT).

[0017] Therefore, one aspect of the present invention relates to the administration of GM-CSF and/or G-CSF to a subject to enhance mobilization of MSCs in vivo and optimization of isolation of BM- derived MSCs and PB-derived MSCs mobilized in the peripheral blood of a subject.

[0018] Accordingly, the present invention relates to a method for obtaining peripheral blood-derived human mesenchymal stem cells from a subject, comprising;

a. administering to the subject an effective amount of G-CSF or GM-CSF for a duration of 4 days or less;

b. obtaining a population of human mesenchymal stem cells from a peripheral blood sample obtained from the subject, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers; and

c. separating human mesenchymal stem cells relative to other somatic stem cells in the peripheral blood.

[0019] The invention further relates to a method for increasing the population of human

mesenchymal stem cells in the peripheral blood of a subject comprising;

a. administering to the peripheral of a subject an effective amount of G-CSF or GM-CSF for a duration of 4 days or less;

[0020] In a specific embodiment of the invention, the effective amount of G-CSF or GM-CSF is administered to the subject for a duration of 3 days or less, for a duration of 2 days or less, or for a duration of 1 days or less. In yet another embodiment of the invention, the subject is a healthy subject.

[0021] Another aspect of the present invention relates to contacting peripheral blood from a subject in the peripheral blood obtained from the subject. Accordingly, the present invention relates to a method for obtaining human mesenchymal stem cells from a subject, comprising;

a. contacting a peripheral blood sample obtained from the subject with an effective

amount of G-CSF or GM-CSF to increase the number of human mesenchymal stem cells in the peripheral blood sample;

b. obtaining a population of human mesenchymal stem cells from the peripheral blood sample, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+ CD90+, CD105+, CD29+ and CD73+ cell surface markers; and

[0022] The invention also relates to a method for obtaining human mesenchymal stem cells from a subject, comprising;

a. contacting the peripheral blood sample in vitro with an effective amount of G-CSF or GM-CSF to increase the number of human mesenchymal stem cells in the peripheral blood sample;

b. isolating a population of human mesenchymal stem cells from the peripheral blood sample, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers.

[0023] In an embodiment of the invention, the peripheral blood sample may be obtained from the subject through apheresis. The peripheral blood sample may be a cultured peripheral blood sample. In yet another embodiment of the invention, the peripheral blood sample may be a fresh peripheral blood sample. The population of stem cells obtained from the peripheral blood may be expanded in culture. Additionally, the human mesenchymal stem cells obtained from the peripheral blood may be cryoperserved.

[0024] In an embodiment of the invention, the population of human mesenchymal stem cells are obtained from the peripheral blood sample using a size-based separation process. The population of human mesenchymal stem cells may also be obtained from the peripheral blood sample using negative selection to exclude non-mesenchymal stem cells, whereby the population of human mesenchymal stem cells are separated and collected from a sample comprising a population of mesenchymal stem cells and a population of non-mesenchymal stem cells. The population of human mesenchymal stem cells can also be obtained from the peripheral blood using a combination of any of following processes; positive selection based on cell surface markers, negative selection based on cell surface markers, positive selection based size, negative selection based size.

[0025] The present invention also relates to a clonal cell line comprising a substantially pure population of human mesenchymal stem cells isolated using the methods of the invention. The clonal cell line may be placed in a container comprising a suitable media. Further the container, containing the suitable media and clonal cell line of a population of human mesenchymal stem cells may be cryopreserved.

[0026] Thus, the inventors provide key advantages over conventional use of G-CSF or GM-CSF for in vivo mobilization by significantly reducing the risk to the subjects and costs associated with mobilization procedures, yet providing a method that optimizes the timing of collecting the cells to a time when the maximum concentration of the cells, e.g., MSCs, are found in the blood, thereby enhancing the yield of the mobilized cells and decreasing contamination by non-MSCs.

[0027] Another aspect of the present invention relates to ex vivo mobilization of MSC from

peripheral blood, where peripheral blood from a subject is contacted with mobilizing agents such as GM-CSF and G-CSF, and peripheral-blood derived MSC are collected and isolated from mobilized peripheral blood ex vivo. In some embodiments, the peripheral blood is freshly isolated from the subject, such as a human subject. In some embodiments, the peripheral blood is from, or has been stored in a blood bank. In some embodiments, the peripheral blood has been stored or preserved, hi some embodiments, the peripheral blood is menstrual blood, as disclosed in U.S. Patent Application, 2008/0241 113, which is incorporated herein in its entirety by reference.

[0028] Another aspect of the present invention relates to the isolation of mesenchymal stem cell (MSCs) at the time point where there is a peak of MSC numbers in the peripheral blood from the mobilization from bone marrow (e.g. BM-derived MSCs) or from peripheral blood (e.g. PB- derived MSCs). In some embodiments, BM-derived MSCs and PB-derived MSCs can be used to generate clonal human mesenchymal progenitor cell lines, and more particularly, in one embodiment provide to a method for generating individual (e.g. subject-specific or personalized) clonal MSC lines from BM-derived MSCs and PB-derived MSC obtained from in vivo or ex vivo mobilized peripheral blood from the subject.

[0029] As discussed herein, the inventors have demonstrated that low doses of GM-CSF and G-CSF administration in vivo (e.g. lower doses as compared to conventional use of GM-CSF and G-CSF as mobilizing agents) is optimal for peak numbers of MSC numbers in the peripheral blood, and for a high yield of mobilized PB-derived and BM-derived MSCs present in the peripheral bl ood in human subjects. Therefore, the inventors have demonstrated low doses of GM-CSF and G-CSF or agonists thereof can be used in vivo for optimal harvesting of MSCs from mobilized peripheral blood for the preparation of compositions for cell therapy using MSCs obtained from a subjects, e.g. a humans peripheral blood.

[0030] In some embodiments, the methods described herein include obtaining bone marrow-derived MSCs or peripheral blood-derived MSCs from the subject. All or a subset of the BM-derived MSCs or PB-derived MSCs can then be administered to a subject, e.g., the same subject from which the MSCs were obtained (e.g. allogenic transplantation) or in certain situations, to a second subject (e.g., non-allogenic transplantation), an HLA type-matched second subject. In some embodiments, the methods also include separating the BM-derived MSCs and/or PB-derived MSCs from the blood, e.g., using apheresis or leukopheresis. In some embodiments, the isolated BM- derived MSCs or PB-derived MSCs can be administered to a subject in need thereof, wherein the subject is the same from which the MSCs were obtained (e.g. allogenic transplantation), or in certain situations to a second subject (e.g., non-allogenic transplantation), such as an HLA type- matched second subject. In some embodiments, the subject in need has a condition selected from the group consisting of cancers and autoimmune disease, or is in need of regenerative therapy.

[0031] In another aspect, the methods described herein include obtaining peripheral blood from the subject, contacting the peripheral blood with an effective amount of a mobilizing agent, such as G- CSF or GM-CSF as described herein, e.g., an amount sufficient to increase the number of PB- derived MSCs in the peripheral blood ex vivo. In some embodiments, the PB-derived MSCs in the peripheral blood can be isolated, enriched or purified, before administration to the subject.

Optionally, in some embodiments, the treated peripheral blood is then administered to a subject, e.g., the same subject or a second subject, e.g., an HLA type-matched second subject.

[0032] One aspect of the present invention relates to the compositions obtained by isolation and culture of mesenchymal stem cells (MSCs) from mobilized peripheral blood. Such compositions are obtained using GM-CSF and G-CSF as a mobilizing agent.

[0033] The present invention relates to the use of a population of human mesenchymal stem cells, or differentiated progeny thereof, for the treatment of a disease or disorder of a subject in need thereof, wherein the population of human mesenchymal stem cells is isolated using a method of any of the above claims, and wherein the population of human mesenchymal stem cells, or differentiated progeny thereof is administered to a subject in need thereof for autologous regeneration therapy. [0034] In one embodiment, the invention is directed to a method of treating a human subject, wherein the number of MSCs are enhanced, and the MSCs are harvested and used in cell transplantation. The methods of the invention employ MSC mobilizing agents, including GM-CSF and G-CSF as described in patents and publications, which are incorporated herein by reference.

[0035] Accordingly, the present invention provides a method for treating a disease or disorder in a subject with autologous mesenchymal stem cells (MSCs) comprising:

a. utilizing a MSC population from a peripheral blood sample, wherein the peripheral blood sample is obtained from a subject who has been administered a mobilizing agent for 4 days or less, and wherein the MSC population is an enriched population of MSCs relative to other stem cells in the peripheral blood; and

b. administering the MSC population to the subject to treat the disease or disorder.

[0036] In an embodiment of the invention, the enrichment of MSCs can by a positive

selection method or by elutriation. The enriched population of MSCs may comprise at least 10% of MSCs. The enriched MSC population may be a substantially pure population of MSCs. The enriched population of MSCs may comprise non-MSC cells.

[0037] Further, the MSC population can be a population of cells that have been

cryopreserved. Additionally, the MSC population of cells may have been expanded in vitro prior to administering to the subject.

[0038] One aspect of the present invention is directed to a method to increase the population of MSC in a peripheral blood sample, where the peripheral blood sample is present within a subject, such as a human subject.

[0039] Another aspect of the present invention relates to a method for enriching a population of BM- derived MSC and/or PB-derived MSCs in a peripheral blood sample from a subject in vivo or ex vivo. In some embodiments, the in vivo method comprises isolating a population of human mesenchymal stem cells from the mesenchymal stem cell-enriched peripheral blood from a subject by (i) administering to the subject at least one mobilizing agent, such as G-CSF or GM-CSF for a duration of 4 days or less; (ii) obtaining a peripheral blood sample from the subject; (iii) isolating a population of MSCs from other cells in the peripheral blood from the subject, and optionally (iv) culturing the MSCs. The steps of culturing and isolating can also be in the inverse order. That is, the PB-derived MSCs or BM-derived MSCs as disclosed herein can be isolated from the peripheral blood and then be culture-expanded. Approaches to such isolation include leukopheresis, density gradient fractionation, immunoselection and differential adhesion separation. The culture media can be chemically defined serum free media or can be a "complete medium," such as DMEM or DMEM-1 g containing serum. Suitable chemically defined serum free media are described in U.S. Ser. No. 08/464,599, filed Jun. 5, 1995, and "complete media" are described in U.S. Pat. No.

5,486,359, issued Jan. 23, 1996. In some embodiments, the BM-derived MSC and/or PB-derived MSC obtained from the subject are expanded or cultured in vitro prior to preservation (e.g.

cry opreservation) .

[0040] In some embodiments, the substantially pure population of human MSCs is obtained from a human subject which has been administered at least one mobilizing agent (e.g. G-CSF and/or GM- CSF) for 4 days or less, is a substantially pure heterologous population of human MSCs, comprising both BM-derived human MSC and PB-derived human MSC.

[0041] In some embodiments, the substantially pure population of human MSCs obtained from a human subject wherein at least one mobilizing agent (e.g. G-CSF and/or GM-CSF) has been administered for 4 days or less, comprises a substantially pure population of BM-derived human MSC. In alternative embodiment, the substantially pure population of human MSCs obtained from a human subject wherein at least one mobilizing agent (e.g. G-CSF and/or GM-CSF) has been administered for 4 days or less, comprises a substantially pure population of PB-derived human MSC.

[0042] Another aspect of the present inventi on relates to a method for enriching a population of PB- derived MSCs in a peripheral blood sample from a subject ex vivo. In some embodiments, the ex vivo method comprises isolating a population of human mesenchymal stem cells from the mesenchymal stem cell-enriched peripheral blood from a subject by contacting a peripheral blood sample previously obtained from the subject with at least one mobilizing agent, such as G-CSF or GM-CSF for a duration of 4 days or less; isolating a population of MSCs from other cells in the peripheral blood sample, and optionally culuiring the MSCs. In some embodiments, the PB-derived MSC obtained from the peripheral blood sample previously obtained from the subject can be preserved. In some embodiments, the preservation is by cryopreservation. In some embodiments, the PB-derived MSC are expanded or cultured in vitro prior to preservation (e.g. cryopreservation).

[0043] Another aspect of the present invention further relates to a method for preserving ex vivo an isolated, PB-derived MSC or BM-derived MSC obtained by the methods as disclosed herein, where the method comprises (i) administering to the subject at least one mobilizing agent, such as G-CSF or GM-CSF for a duration of 4 days or less; (ii) obtaining a peripheral blood sample from the subject; (iii) isolating a population of MSCs from other cells in the peripheral blood from the subject, and optionally (iv) culturing the MSCs; and (v) preserving the isolated, PB-derived MSG or BM-derived MSC. Preferably, the preservation is by cryopreservation.

[0044] Another aspect of the present invention relates to a method for treating an subject in need of treatment with a substantially pure population of PB-derived MSC and/or BM-derived MSC obtained by the methods as disclosed herein, the method comprising administering to a subject a substantially pure population of PB-derived MSC or BM-derived MSC. In some embodiments, the PB-derived MSC or BM-derived MSC have been freshly isolated by the methods as disclosed herein, or in some embodiments, the PB-derived MSC or BM-derived MSC have been

cryopreserved by known methods commonly used by a skilled artisan. In some embodiments, a substantially pure population of PB-derived MSCs and/or BM-derived MSCs can be administered by, for example, systemic infusion or local implantation into a site where de novo tissue generation is desired, such as by an open or arthroscopic procedure. The cells can be preserved prior to re- administration.

[0045] One aspect of the present invention relates to a method for obtaining peripheral blood-derived human mesenchymal stem cells from a subject, comprising; (a) administering to the subject an effective amount of G-CSF or GM-CSF to the subject for a duration of 4 days or less; (b) obtaining a population of human mesenchymal stem cells from a peripheral blood sample obtained from the subject, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers. In some embodiments, the present invention relates to a method for increasing the population of human mesenchymal stem cells in the peripheral blood of a subject comprising; (a) administering to the subject an effective amount of G-CSF or GM-CSF to the subject for a duration of 4 days or less; (b) obtaining a population of human mesenchymal stem cells from a peripheral blood sample obtained from the subject, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers, and (c) separating human mesenchymal stem cells relative to somatic stem cells in the peripheral blood.

[0046] Another aspect of the present invention relates to a method for obtaining human

mesenchymal stem cells from a subject, comprising; (a) contacting a peripheral blood sample obtained from the subject with an effective amount of G-CSF or GM-CSF to increase the number of human mesenchymal stem cells in the peripheral blood sample; (b) obtaining a population of human mesenchymal stem cells from the peripheral blood sample, wherein the human

mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers; and (c) separating human mesenchymal stem cells realative to somatic stem cells in the peripheral blood.

[0047] In some embodiments, the methods comprises administration of a mobilizing agent such as an effective amount of G-CSF or GM-CSF, or AM3100 to the subject for a duration of 3 days or less. In some embodiments, an effective amount of a mobilizing agent, such as G-CSF or GM-CSF or AM3100 is administered to the subject for a duration of 2 days or less, or a duration of 1 days or less. In some embodiments, an effective amount of a mobilizing agent is administered to a healthy subject.

[0048] In some embodiments, a population of human mesenchymal stem cells are obtained from the peripheral blood sample using a size-based separation process, such as elutriation. In some embodiments, a population of human mesenchymal stem cells are obtained from the peripheral blood sample using negative selection to exclude non-mesenchymal stem cells, whereby population of human mesenchymal stem cells are separated and collected from a sample comprising a population of mesenchymal stem cells and a population of non-mesenchymal stem cells.

[0049] In some embodiments, a population of human mesenchymal stem cells are obtained from the peripheral blood using a combination of any of following processes; positive selection based on cell surface markers, negative selection based on cell surface markers, positive selection based size, negative selection based size.

[0050] Another aspect of the present invention relates to a method for obtaining human

mesenchymal stem cells from a subject, comprising; (a) contacting the peripheral blood sample in vitro with an effective amount of G-CSF or GM-CSF to increase the number of human

mesenchymal stem cells in the peripheral blood sample; (b) isolating a population of human mesenchymal stem cells from the peripheral blood sample, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers, and (c) separating human mesenchymal stem cells realative to somatic stem cells in the peripheral blood.

[0051] In some embodiments, the MSCs are obtained from a cultured mobilized peripheral blood sample. In some embodiments, the MSCs are obtained from a peripheral blood sample is a fresh peripheral blood sample. In some embodiments, the MSCs are obtained from a population of human mesenchymal stem cells obtained from the peripheral blood sample is expanded in culture. In some embodiments, a population of human mesenchymal stem cells obtained from the peripheral blood sample is cryopreserved. [0052] In some embodiments, the subject is a human subject. Another aspect of the present invention relates to a clonal cell line comprising a substantially pure population of human mesenchymal stem cells isolated using a method of any of the above claims.

[0053] Another aspect of the present invention relates to a container comprising a suitable media and a clonal cell line of a population of human mesenchymal stem cell obtained by the methods as disclosed herein. In some embodiments, the suitable media and clonal cell line of a population of human mesenchymal stem cell are cryopreserved.

[0054] Another aspect of the present invention relates to a cryopreserved population of human mesenchymal stem cell obtained by any of the methods as disclosed herein. Another aspect of the present invention relates to the use of a population of human mesenchymal stem cells, or a differentiated progeny thereof, for the treatment of a disease or disorder of a subject in need thereof, wherein a population of human mesenchymal stem cells is isolated using a method of any of the above claims, and wherein the population of human mesenchymal stem cells, or a differentiated progeny thereof is administered to a subject in need thereof for autologous regeneration therapy.

[0055] Another aspect of the present invention relates to a method for treating a disease or disorder in a subject with autologous mesenchymal stem cells (MSCs) comprising: (a) utilizing a MSC population from a peripheral blood sample, wherein the peripheral blood sample is obtained from a subject wherein a mobilizing agent has been administered for 4 days or less, and wherein the MSC population is an enriched population of MSCs relative to other stem cell populations in the blood; and (b) administering the MSC population to the subject to treat the disease or disorder. In some embodiments, the enrichment of MSCs is by a positive selection method, in alternative

embodiments, the enrichment of MSCs is by elutriation.

[0056] In some embodiments, the MSC population as been cryopreserved. In some embodiments, the enriched population of MSCs comprises non-MSC cells, or in some embodiments, the enriched population of MSCs comprises at least 10% of MSCs or a substantially pure population of MSCs. In some embodiments, the MSC population has been expanded in vitro prior to administering to the subject. In some embodiments, the subject is a human subject.

[0057] The present invention further provides a method for obtaining peripheral blood- derived human stem cells from a subject, comprising;

a. administering to the subject an effective amount of a mobilization agent for a

duration of 4 days or less; b. obtaining a population of human stem cells from a peripheral bl ood sample obtained from the subject; and

c. separating human stem cells relative to other somatic stem cells in the peripheral blood.

[0058] In a specific embodiment of the invention, the stem cells are mesenchymal stem cell, or "very small embryonic -like stem cells (VSEL). Further, the mobilization agent may be G- CSF or GM-CSF. Alternatively, the mobilization agent is selected from the group consisting of interleukin-17, AMD3100 , cyclophosphamide (Cy), Docetaxel and (DXT).

BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figures lA-lD show mobilized peripheral blood-derived human MSCs adhere and expand in vitro. Figures 1 A and IB show mobilized peripheral blood-derived human MSCs cultured in DMEM with 10% FBS (fetal bovine serum) and plated at 1,000,000 cells/place (Fig. 1A) and 2,000,000 cells/plate (Fig. IB). Figures 1C and ID show mobilized peripheral blood-derived human MSCs cultured in MesenCult-MSC (* trademark?) and plated at 1,000,000 cells/place (Fig. 1C) and 2,000,000 cells/plate (Fig. ID).

[0060] Figures 2A-2D show the peripheral blood-derived human MSCs are CD45- and CD105+. Figure 2 A shows FACs of Apherosis product based on marker expression of CD45. Figure 2B shows FACs of adherent cells based on marker expression of CD45. Adherent cell are enriched in cells which do not express CD45. Figure 2C shows FACs of apheresis product based on marker expression of CD 105. Figure 2D shows FACs of adherent cells based on marker expression of CD105. Adherent cell are enriched in cells which are positive for expression of CD105.

[0061] Figures 3A-3D show the peripheral blood-derived human MSCs are CD90+ and CD105+. Figure 3A shows FACs of floating cells based on marker expression of CD90. Most of the floating cells are negative for CD90 expression. Figure 3B shows FACs of adherent cells after one passage (PI) based on marker expression of CD45. Adherent cells (at passage 1) are enriched in cells which express CD90. Figure 3C shows FACs of floating cells based on marker expression of CD105. Most of the floating cells are negative for CD 105 expression. Figure 3D show^rs FACs of adherent cells after one passage (Pi) based on marker expression of CD 105. Adherent cells (at passage 1 ) are enriched in cells which express CD 105.

[0062] Figures 4A-4B show the peripheral blood-derived human MSCs are CD44+. Figure 4A shows FACs of floating cells based on marker expression of CD44. Most of the floating cells are negative for CD44 expression. Figure 4B shows FACs of adherent cells after one passage (PI) based on marker expression of CD44. Adherent cells (at passage 1) are enriched in cells which express CD44.

[0063] Figure 5 is a schematic demonstrating the steps used to isolate a population of MSCs from mobilized peripheral blood.

[0064] Figure 6 shows the number of MSCs in peripheral blood Pre- and Post G-CSF mobilization.

DETAILED DESCRIPTION OF THE INVENTION

[0065] Mesenchymal Stem cells (MSCs) are non-hematopoietic stem cells which are normally obtained from the bone marrow. MSCs are present at very low levels in the peripheral blood and harvesting from peripheral blood results in insufficient amounts, even if they are in vitro expanded, for therapeutic uses. The inventors have discovered that MSCs can be obtained from mobilized peripheral blood. In particular, MSCs can be obtained and collected from a subject who has been administered a mobilizing agent (e.g. but not limited to G-CSF, GM-CSF, AMD3100 etc) for 4 days or less, such as for about 2 days, collected using apheresis and elutriation. In some

embodiments, the isolated human MSC from mobilized peripheral blood can be expanded in culture and/or cryopreserved for future use, e.g. where the MSCs can be used either alone or in combination with other cells, for future autologous therapeutic applications in regenerative therapy, such as wound healing and bone repair and other orthopedic indications.

[0066] The inventors have surprisingly discovered that the mobilization of MSC into the peripheral blood is temporally regulated and that the number of circulating MSCs in human peripheral blood peaks after at least 1 day post administration of a mobilizing agent, such as G-CSF or GM-CSF to a human subject. Accordingly, the inventors have demonstrated that the protocol wherein G-CSF or GM-CSF is used to optimize the mobilization of MSCs into the peripheral blood is different from that typically used for mobilization of other stem cells, such as CD34+ HSCs into the peripheral blood.

[0067] The inventors have unexpectedly discovered that a short duration, e.g. for at least 2 days but less than 4 days post administration of G-CSF or GM-CSF to a human subject resulted in the highest yield of MSC in the mobilized peripheral blood, rather than the conventional use of a 5-day administration protocol of G-CSF or GM-CSF to the subject. Accordingly, the inventors have determined that the administration protocol of a stem cell mobilizing agent, such as G-CSF or GM- CSF needs to be optimized for a particular desired application, by administering G-CSF or GM- CSF under different conditions, and then monitoring the output of the desired subset of stem cells, such as MSCs, VESLs, hematopoietic cells in the peripheral blood according to the methods commonly known by persons skilled in the art and as disclosed herein. The time period after administration of a mobilizing agent, such as G-CSF or GM-CSF should be monitored for optimal recovery or induction of specific cell populations in the blood, because the appearance of different cell types occurs sequentially over a period of time following administration of the mobilizing agent.

[0068] Another aspect of the present invention relates to the use of the MSCs, obtained from an individuals mobilized peripheral blood, for personalized medicine applications, such as autologous therapeutic use, as well as in a personalized assay to assess the effect of a persons diet, phamacogenetics, neurochemicals, lifestyle on the function and viability of MSCs.

[0069] Definitions

[0070] For convenience, certain terms employed herein, in the specification, examples and appended claims are collected here. Unless stated otherwise, or implicit from context, the following terms and phrases include the meanings provided below. Unless explicitly stated otherwise, or apparent from context, the terms and phrases below do not exclude the meaning that the term or phrase has acquired in the art to which it pertains. The definitions are provided to aid in describing particular embodiments, and are not intended to limit the claimed invention, because the scope of the invention is limited only by the claims. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0071] The term "mesenchymal stem cell" is also referred to herein as a "MSC" refers to pluripotent stem cells capable of differentiating into more than one specific type of mesenchymal or connective tissue (i.e. tissues of the body which support specialized elements; e.g. adipose, osseous, stroma, cartilaginous, elastic and fibrous connective tissues). Human mesenchymal stem cells (hMSCs) are reactive with certain monoclonal antibodies, know^rn as SH2, SH3 and SH4. (See U.S. Pat. No. 5,486,359, which is incorporated herein in its entirety by reference). MSCs can be differentiated from HSCs based on their immunospecific profiles and, with MSCs being

SH2⁺/CD14^" and human HSCs SH27CD14^T. For purposes of identification, human MSCs can be identified based on (i) phenotypic marker expression of CD34^", CD45^", CD90^*, CD 105^" and CD44^†, (ii) functional phenotype, including the ability to form colony forming units in a CFA assay as disclosed in the Examples herein, and ability to differentiate into tissues which support specialized elements, including but not limited to; chondrocytes, cartilage and adipocytes. Other markers expressed by MSCs are known in the art and include without limitation CD71 , CD73, Stro-1, CD 166 and CD271. In certain embodiments, MSCs are lin^".

[0072] The term "very small embryonic-like stem cell" is also referred to herein as "VSEL stem cell" and refers to pluripotent stem cells. In some embodiments, the VSEL stem cells ("VSELs") are human VSELs and may be characterized as lin , CD45^", and CD34^÷. In some embodiments, the VSELs are human VSELs and may be characterized as lin^", CD45^", and CD133⁺. In some embodiments, the VSELs are human VSELs and may be characterized as lin^", CD45^", and

CXCR4⁺. In some embodiments, the VSELs are human VSELs and may be characterized as lin^", CD45^", CXCR4⁺, CD133⁺, and CD34⁺. Human VSELs express at least one of SSEA-4, Oct-4, Rex-1 , and Nanog, and possess large nuclei surrounded by a narrow rim of cytoplasm, and contain embryonic -type unorganized chromatin. VSELs also have high telomerase activity. In some embodiments, the VSELs are human VSELs and may be characterized as lin^", CD45^", CXCR4⁺, CD133^*, Oct 4⁺, SSEA4⁺, and CD34⁺. In some embodiments, the human VSELs may be less primitive and may be characterized as lin^", CD45^", CXCR4⁺, CD133^", and CD34⁺. In some embodiments, the human VSELs may be enriched for pluripotent embryonic transcription factors, e.g., Oct-4, Sox2, and Nanog. In some embodiments, the human VSELs may have a diameter of 4- 5 μιη, 4-6 μιη, 4-7 μιτι, 5-6 μηι, 5-8 urn, 6-9 μιη, or 7-10 μηι.

[0073] The term "peripheral blood-derived MSC" or "PB-MSC" as used herein refers to MSCs which are mobilized from the peripheral blood only, and can include expansion or proliferation of MSCs in the peripheral blood. In some embodiments, the number of circulating PB-MSCs can be increased in the peripheral blood by contacting the peripheral blood with a mobilizing agent, either in vivo or ex vivo, according to the methods as disclosed herein.

[0074] The term "bone marrow-derived MSC" or "BM-MSC" as used herein refers to MSCs which are mobilized from the bone marrow to the peripheral blood, and can include MSCs which have migrated from the BM. In some embodiments, BM-MSCs in the peripheral blood includes MSCs which have proliferated in the bone marrow prior to migration to the peripheral blood, or alternatively MSCs which have proliferated in the peripheral blood after migration from the bone marrow. In some embodiments, the number of circulating BM-MSCs can be increased in the peripheral blood by contacting the peripheral blood with a mobilizing agent in vivo according to the methods as disclosed herein.

[0075] The term "hematopoietic stem cells" also referred to as "HSCs" refers to all stem cells or progenitor cells found inter alia in bone marrow and peripheral blood that are capable of differentiating into any of the specific types of hematopoietic or blood cells, such as erythrocytes. lymphocytes, macrophages and megakaryocytes. HSCs are reactive with certain monoclonal antibodies which are now recognized as being specific for hematopoietic cells, for example, CD34.

[0076] The term "hematopoietic cells" also referred to as "HSCs" refers to all types of hematopoietic cells throughout their differentiation from self-renewing hematopoietic stem cells through immature precursor cells of the various blood lineages to and including the mature functioning blood cells as would be understood by persons skilled in the art.

[0077] The term "mobilization" as used herein refers to the process whereby the cells leave the bone marrow and enter the blood. Mobilization may be effectuated by a combination of

chemoattractants (e.g. cytokines) and loss of adhesiveness of pools or populations of stem cells residing in stem cell niches in peripheral tissues and the bone marrow.

[0078] An "effective amount" is an amount sufficient to effect a significant increase in the number and/or frequency of MSCs in the peripheral blood. An effective amount can be administered in one or more administrations, applications or dosages. A therapeutically effective amount of a mobilizing agent depends on the mobilizing agent selected, e.g. G-CSF or GM-CSF. The mobilizing agent, such as G-CSF or GM-CSF can be administered from one or more times per day to one or more times per week; including once every other day. The skilled artisan will appreciate that certain factors may influence the dosage and timing required to effectively treat a subject, including but not limited to previous treatments, the general health and/or age of the subject, and other diseases present. Moreover, treatment of a subject with a therapeutically effective amount of the G-CSF or GM-CSF as described herein can include a single treatment or a series of treatments.

[0079] The terms "mesenchymal cell" or "mesenchyme" are used interchangeably herein and refer in some instances to the fusiform or stellate cells found between the ectoderm and endoderm of young embryos; most mesenchymal cells are derived from established mesodermal layers, but in the cephalic region they also develop from neural crest or neural tube ectoderm. Mesenchymal cells have a pluripotential capacity, particularly embryonic mesenchymal cells in the embryonic body, developing at different locations into any of the types of connective or supporting tissues, to smooth muscle, to vascular endothelium, and to blood cells.

[0080] As used herein, the term "stem cells" is used in a broad sense and includes traditional stem cells, progenitor cells, preprogenitor cells, reserve cells, and the like. The term "stem cell" or "progenitor" are used interchangeably herein, and refer to an undifferentiated cell w^rhich is capable of proliferation and giving rise to more progenitor cells having the ability to generate a large number of mother cells that can in turn give rise to differentiated, or differentiable daughter cells. The daughter cells themselves can be induced to proliferate and produce progeny that subsequently differentiate into one or more mature cell types, while also retaining one or more cells with parental developmental potential. The term "stem cell" refers then, to a cell with the capacity or potential, under particular circumstances, to differentiate to a more specialized or differentiated phenotype, and which retains the capacity, under certain circumstances, to proliferate without substantially differentiating. In one embodiment, the term progenitor or stem cell refers to a generalized mother cell whose descendants (progeny) specialize, often in different directions, by differentiation, e.g., by acquiring completely individual characters, as occurs in progressive diversification of embryonic cells and tissues. Cellular differentiation is a complex process typically occurring through many cell divisions. A differentiated cell may derive from a multipotent cell which itself is derived from a multipotent cell, and so on. While each of these multipotent cells may be considered stem cells, the range of cell types each can give rise to may vary considerably. Some differentiated cells also have the capacity to give rise to cells of greater developmental potential. Such capacity may be natural or may be induced artificially upon treatment with various factors. In many biological instances, stem cells are also "multipotent" because they can produce progeny of more than one distinct cell type, but this is not required for "stem-ness." Self-renewal is the other classical part of the stem cell definition, and it is essential as used in this document. In theory, self-renew^ral can occur by either of two major mechanisms. Stem cells may divide asymmetrically, with one daughter retaining the stem state and the other daughter expressing some distinct other specific function and phenotype. Alternatively, some of the stem cells in a population can divide symmetrically into two stem cells, thus maintaining some stem cells in the population as a whole, while other cells in the population give rise to differentiated progeny only. Formally, it is possible that cells that begin as stem cells might proceed toward a differentiated phenotype, but then "reverse" and re-express the stem cell phenotype, a term often referred to as "dedifferentiation".

081] Exemplary stem cells include embryonic stem cells, adult stem cells, pluripotent stem cells, neural stem cells, liver stem cells, muscle stem cells, muscle precursor stem cells, endothelial progenitor cells, bone marrow stem cells, chondrogenic stem cells, lymphoid stem cells, mesenchymal stem cells, hematopoietic stem cells, central nervous system stem cells, peripheral nervous system stem cells, and the like. Descriptions of stem cells, including method for isolating and culturing them, may be found in, among other places, Embryonic Stem Cells, Methods and Protocols, Turksen, ed., Humana Press, 2002; Weisman et al., Annu. Rev. Cell. Dev. Biol. 17:387 403; Pittinger et al, Science, 284: 143 47, 1999; Animal Cell Culture, Masters, ed., Oxford

University Press, 2000; Jackson et al, PNAS 96(25): 14482 86, 1999; Zuk et al., Tissue Engineering, 7:211 228, 2001 ("Zuk et al."); Atala et al., particularly Chapters 33 41 ; and U.S. Pat. Nos. 5,559,022, 5,672,346 and 5,827,735. Descriptions of stromal cells, including methods for isolating them, may be found in, among other places, Prockop, Science, 276:71 74, 1997; Theise et al., Hepatology, 31 :235 40, 2000; Current Protocols in Cell Biology, Bonifacino et al., eds., John Wiley & Sons, 2000 (including updates through March, 2002); and U.S. Pat. No. 4,963,489.

[0082] The term "progenitor cell" is used herein to refer to cells that have a cellular phenotype that is more primitive (e.g., is at an earlier step along a developmental pathway or progression than is a fully differentiated cell) relative to a cell which it can give rise to by differentiation. Often, progenitor cells also have significant or very high proliferative potential. Progenitor cells can give rise to multiple distinct differentiated cell types or to a single differentiated cell type, depending on the developmental pathway and on the environment in which the cells develop and differentiate.

[0083] As indicated above, there are different levels or classes of cells falling under the general definition of a "stem cell." These are "totipotent," "pluripotent" and "multipotent" stem cells. The term "totipotent" refers to a stem cell that can give rise to any tissue or cell type in the body.

"Pluripotent" stem cells can give rise to any type of cell in the body except germ line cells. Stem cells that can give rise to a smaller or limited number of different cell types are generally termed "multipotent." Thus, totipotent cells differentiate into pluripotent cells that can give rise to most, but not all, of the tissues necessary for fetal development. Pluripotent cells undergo further differentiation into multipotent cells that are committed to give rise to cells that have a particular function. For example, multipotent hematopoietic stem cells give rise to the red blood cells, white blood cells and platelets in the blood.

[0084] The term "pluripotent" as used herein refers to a cell with the capacity, under different conditions, to differentiate to cell types characteristic of all three germ cell layers (endoderm, mesoderm and ectoderm). Pluripotent cells are characterized primarily by their ability to differentiate to all three germ layers, using, for example, a nude mouse teratoma formation assay. Pluripotency is also evidenced by the expression of embryonic stem (ES) cell markers, although the preferred test for pluripotency is the demonstration of the capacity to differentiate into cells of each of the three germ layers. In some embodiments, a pluripotent cell is an undifferentiated cell.

[0085] The term "pluripotency" or a "pluripotent state" as used herein refers to a cell with the ability to differentiate into all three embryonic germ layers: endoderm (gut tissue), mesoderm (including blood, muscle, and vessels), and ectoderm (such as skin and nerve), and typically has the potential to divide in vitro for a long period of time, e.g., greater than one year or more than 30 passages. [0086] The term "multipotent" when used in reference to a "multipotent cell" refers to a cell that is able to differentiate into some but not all of the cells derived from all three germ layers. Thus, a multipotent cell is a partially differentiated cell. Multipotent cells are well known in the art, and examples of muiltipotent cells include adult stem cells, such as for example, hematopoietic stem cells and neural stem cells. Multipotent means a stem cell may form many types of cells in a given lineage, but not cells of other lineages. For example, a multipotent blood stem cell can form the many different types of blood cells (red, white, platelets, etc.), but it cannot form neurons.

[0087] The term "multipotency" refers to a cell with the degree of developmental versatility that is less than totipotent and pluripotent.

[0088] The term "totipotency" refers to a cell with the degree of differentiation describing a capacity to make all of the cells in the adult body as well as the extra-embryonic tissues including the placenta. The fertilized egg (zygote) is totipotent as are the early cleaved cells (blastomeres)

[0089] The term "isolated cell" as used herein refers to a cell that has been removed from a subject in which it was originally found or a descendant of such a cell. Optionally the cell has been cultured in vitro, e.g., in the presence of other cells. Optionally the cell, e.g. an isolated PB-derived MSCs or an isolated BM-derived MSCs produced by the method as disclosed herein is later introduced into a second subject or re-introduced into the subject from witich it (or the cell from which it is descended) was isolated (e.g. allogenic transplantation).

[0090] The term "isolated population" with respect to an isolated population of cells as used herein refers to a population of cells that has been removed and separated from a mixed or heterogeneous population of cells. In some embodiments, an isolated population is a substantially pure population of cells as compared to the heterogeneous population from which the cells were isolated or enriched from. In some embodiments, the isolated population is an isolated population of reprogrammed cells which is a substantially pure population of reprogrammed cells as compared to a heterogeneous population of cells comprising reprogrammed cells and cells from which the reprogrammed cells were derived.

[0091] The term "substantially pure", with respect to a particular cell population, refers to a population of cells that is at least about 75%, preferably at least about 85%, more preferably at least about 90%, and most preferably at least about 95% pure, with respect to the cells making up a total cell population. Recast, the terms "substantially pure" or "essentially purified", with regard to a population of PB-derived MSCs or BM-derived MSCs isolated using the methods as disclosed herein, refers to a population of PB-derived MSCs or BM-derived MSCs that contain fewer than about 20%, more preferably fewer than about 15%, 10%, 8%, 7%, most preferably fewer than about 5%, 4%, 3%, 2%, 1%, or less than 1%, of cells that are not PB-derived MSCs or BM-derived MSCs s as defined by the terms herein. In some embodiments, the present invention encompasses methods to expand a population of PB-derived M SCs or BM-derived M SCs, wherein the expanded population of PB-derived MSCs or BM-derived MSCs is a substantially pure population of PB- derived MSCs or BM-derived MSCs.

[0092] As used herein, "proliferating" and "proliferation" refers to an increase in the number of cells in a population (growth) by means of cell division. Cell proliferation is generally understood to result from the coordinated activation of multiple signal transduction pathways in response to the environment, including growth factors and other mitogens. Cell proliferation may also be promoted by release from the actions of intra- or extracellular signals and mechanisms that block or negatively affect cell proliferation.

[0093] The term "regeneration" means regrowth of a cell population, organ or tissue after disease or trauma.

[0094] The terms "enriching" or "enriched" are used interchangeably herein and mean that the yield (fraction) of cells of one type is increased by at least 10% over the fraction of cells of that type in the starting culture or preparation.

[0095] The terms "renewal" or "self-renewal" or "proliferation" are used interchangeably herein, and refers to a process of a cell making more copies of itself (e.g. duplication) of the cell. In some embodiments, reprogrammed cells are capable of renewal of themselves by dividing into the same undifferentiated cells (e.g. pluripotent or non-specialized cell type) over long periods, and/or many months to years. In some instances, proliferation refers to the expansion of reprogrammed cells by the repeated division of single cells into two identical daughter cells.

[0096] The term "lineages" as used herein refers to a term to describe cells with a common ancestry or cells with a common developmental fate, for example cells that are derived from the same PB-derived MSCs or BM-derived MSCs or progeny thereof.

[0097] As used herein, the term "clonal cell line" refers to a cell lineage that can be maintained in culture and has the potential to propagate indefinitely. A clonal cell line can be a stem cell line (e.g. a PB-derived MSCs or BM-derived MSCs cell line) or be derived from a PB-derived MSC or a BM-derived MSC , and where the clonal cell line is used in the context of a clonal cell line comprising PB-derived MSCs or BM-derived MSCs, the term refers to PB-derived MSCs or BM- derived MSCs which have been cultured under in vitro conditions that allow proliferation without differentiation for months to years. Such clonal stem cell lines (e.g. PB-derived MSCs or BM- derived MSCs) can have the potential to differentiate along several lineages of the cells from the original stem cell.

[0098] In the context of cell ontogeny, the adjective "differentiated", or "differentiating" is a relative term. A "differentiated cell" is a cell that has progressed further down the developmental pathway than the cell it is being compared with. Thus, stem cells can differentiate to lineage- restricted precursor cells (such as a mesodermal stem cell), which in turn can differentiate into other types of precursor cells further down the pathway (such as an cardiomyocyte precursor), and then to an end-stage differentiated cell, which plays a characteristic role in a certain tissue type, and may or may not retain the capacity to proliferate further.

[0099] The term "differentiation" in the present context means the formation of cells expressing markers known to be associated with cells that are more specialized and closer to becoming terminally differentiated cells incapable of further differentiation. The pathway along which cells progress from a less committed cell, to a cell that is increasingly committed to a particular cell type, and eventually to a terminally differentiated cell is referred to as progressive differentiation or progressive commitment. Cells which are more specialized (e.g., have begun to progress along a path of progressive differentiation) but not yet terminally differentiated are referred to as partially differentiated. Differentiation is a developmental process whereby cells assume a specialized phenotype, e.g., acquire one or more characteristics or functions distinct from other cell types. In some cases, the differentiated phenotype refers to a cell phenotype that is at the mature endpoint in some developmental pathway (a so called terminally differentiated cell). In many, but not all tissues, the process of differentiation is coupled with exit from the cell cycle. In these cases, the terminally differentiated cells lose or greatly restrict their capacity to proliferate. However, we note that in the context of this specification, the terms "differentiation" or "differentiated" refer to cells that are more specialized in their fate or function than at a previous point in their development, and includes both cells that are terminally differentiated and cells that, although not terminally differentiated, are more specialized than at a previous point in their development. The development of a cell from an uncommitted cell (for example, a stem cell), to a cell with an increasing degree of commitment to a particular differentiated cell type, and finally to a terminally differentiated cell is known as progressive differentiation or progressive commitment. A cell that is "differentiated" relative to a progenitor cell has one or more phenotypic differences relative to that progenitor cell. Phenotypic differences include, but are not limited to morphologic differences and differences in gene expression and biological activity, including not only the presence or absence of an expressed marker, but also differences in the amount of a marker and differences in the co-expression patterns of a set of markers. [00100] The term "differentiation" as used herein refers to the cellular development of a cell from a primitive stage towards a more mature (i.e. less primitive) cell.

[00101] The term "directed differentiation" as used herein refers to forcing differentiation of a cell from an undifferentiated (e.g. more primitive cell) to a more mature cell type (i.e. less primitive cell) via genetic and/or environmental manipulation. In some embodiments, a reprogrammed cell as disclosed herein is subject to directed differentiation into specific cell types, such as neuronal cell types, muscle cell types and the like.

[00102] The term "media" as referred to herein is a medium for maintaining a tissue or cell population, or culturing a cell population (e.g. "culture media") containing nutrients that maintain cell viability and support proliferation. The cell culture medium may contain any of the following in an appropriate combination: salt(s), buffer(s), amino acids, glucose or other sugar(s), antibiotics, serum or serum replacement, and other components such as peptide growth factors, etc. Cell culture media ordinarily used for particular cell types are known to those skilled in the art.

[00103] The term "phenotype" refers to one or a number of total biological characteristics that define the cell or organism under a particular set of environmental conditions and factors, regardless of the actual genotype.

[00104] A "marker" as used herein describes the characteristics and/or phenotype of a cell.

Markers can be used for selection of cells comprising characteristics of interest. Markers will vary with specific cells. Markers are characteristics, whether morphological, functional or biochemical (enzymatic) characteristics particular to a cell type, or molecules expressed by the cell type.

Preferably, such markers are proteins, and more preferably, possess an epitope for antibodies or other binding molecules available in the art. However, a marker may consist of any molecule found in a cell including, but not limited to, proteins (peptides and polypeptides), lipids, polysaccharides, nucleic acids and steroids. Examples of morphological characteristics or traits include, but are not limited to, shape, size, and nuclear to cytoplasmic ratio. Examples of functional characteristics or traits include, but are not limited to, the ability to adhere to particular substrates, ability to incorporate or exclude particular dyes, ability to migrate under particular conditions, and the ability to differentiate along particular lineages. Markers may be detected by any method available to one of skill in the art.

[00105] The term "contacting" or "contact" as used herein as in connection with contacting a peripheral blood sample in vivo, can comprise administering a mobilizing agent, optionally in a composition, to a subject via an appropriate administration route such that the compound contacts the peripheral blood sample in vivo. The term "contacting" or "contact" as used herein as in connection with contacting a peripheral blood sample ex vivo, can comprise administering a mobilizing agent, optionally in a composition, to a peripheral blood sample such that the mobilizing agent contacts the peripheral blood sample ex vivo.

[00106] As used herein, the terms "administering," "introducing" and "transplanting" are used interchangeably and refer to the placement of the peripheral blood-derived MSCs or bone-marrow- derived MSCs as described herein into a subject by a method or route which results in at least partial localization of the human PB-derived MSCs or BM-derived MSCs at a desired site. The human PB-derived MSCs or BM-derived MSCs can be administered by any appropriate route which results in delivery to a desired location in the subject where at least a portion of the human PB-derived MSCs or BM-derived MSCs remain viable. The period of viability of the cells after administration to a subject can be as short as a few hours, e. g. twenty-four hours, to a few days, to as long as several years.

[00107] As used herein, the term "donor" refers to a subject to which a organ, tissue or cell to be transplanted is harvested from.

[00108] As used herein, the term "recipient" refers to a subject which will receive a transplanted organ, tissue or cell.

[00109] The term "graft" as used herein refers to the process whereby a free (unattached) cell, tissue, or organ integrates into a tissue following transplantation into a subject.

[00110] The term "allograft" refers to a transplanted cell, tissue, or organ derived from a different animal of the same species.

[00111] The term "xenograft" or "xenotransplant" as used herein refers to a transplanted cell, tissue, or organ derived from an animal of a different species. In some embodiments, a xenograft is a surgical graft of tissue from one species to an unlike species, genus or family. By way of an example, a graft from a baboon to a human is a xenograft.

[00112] The term "xenotransplantation" refers to the process of transplantation of living cells, tissues or organs from one species to another, such as from pigs to humans.

[00113] The terms "subject" and "individual" are used interchangeably herein, and refer to an animal, for example a human, to whom PB-derived MSCs and BM-MSCs as disclosed herein can be isolated and collected from according to the methods and compositions described herein, and optionally, a subject can receive a transplantation (e.g. the PB-derived MSCs or BM-derived MSCs can be implanted into), for example for the treatment, including prophylactic treatment of a disease. For treatment of disease states which are specific for a specific animal such as a human subject, the term "subject" refers to that specific animal. The terms "non-human animals" and "non-human mammals" are used interchangeably herein, and include mammals such as rats, mice, rabbits, sheep, cats, dogs, cows, pigs, and non-human primates. The term "subject" also encompasses any vertebrate including but not limited to mammals, reptiles, amphibians and fish. However, advantageously, the subject is a mammal such as a human, or other mammals such as a domesticated mammal, e.g. dog, cat, horse, and the like, or production mammal, e.g. cow, sheep, pig, and the like are also encompassed in the term subject.

[00114] The term "tissue" refers to a group or layer of similarly specialized cells which together perform certain special functions. The term "tissue-specific" refers to a source or defining characteristic of cells from a specific tissue.

[00115] The term "agent" as used herein means any compound or substance such as, but not limited to, a small molecule, nucleic acid, polypeptide, peptide, drug, ion, etc. An "agent" can be any chemical, entity or moiety, including without limitation synthetic and naturally-occurring proteinaceous and non-pro teinaceous entities. In some embodiments, an agent is nucleic acid, nucleic acid analogues, proteins, antibodies, peptides, aptamers, oligomer of nucleic acids, amino acids, or carbohydrates including without limitation proteins, oligonucleotides, ribozymes, DNAzymes, glycoproteins, siRNAs, lipoproteins, aptamers, and modifications and combinations thereof etc. In certain embodiments, agents are small molecules having a chemical moiety. For example, chemical moieties included unsubstituted or substituted alkyl, aromatic, or heterocyclyl moieties including macrolides, leptomycins and related natural products or analogues thereof Compounds can be known to have a desired activity and/or property, or can be selected from a library of diverse compounds.

[00116] As used herein, the term "small molecule" refers to a chemical agent which can include, but is not limited to, a peptide, a peptidomimetic, an amino acid, an amino acid analog, a polynucleotide, a polynucleotide analog, an aptamer, a nucleotide, a nucleotide analog, an organic or inorganic compound (e.g., including heterorganic and organometallic compounds) having a molecular weight less than about 10,000 grams per mole, organic or inorganic compounds having a molecular weight less than about 5,000 grams per mole, organic or inorganic compounds having a molecular weight less than about 1 ,000 grams per mole, organic or inorganic compounds having a molecular weight less than about 500 grams per mole, and salts, esters, and other pharmaceutically acceptable forms of such compounds.

[00117] The term "disease" or "disorder" is used interchangeably herein, and refers to any alternation in the state of the body or of some of the organs, interrupting or disturbing the performance of the functions and/or causing symptoms such as discomfort, dysfunction, distress, or even death to the person afflicted or those in contact with a person. A disease or disorder can also related to a distemper, ailing, ailment, malady, disorder, sickness, illness, complaint, indisposition or affection.

[00118] The term "pathology" as used herein, refers to symptoms, for example, structural and functional changes in a cell, tissue, or organs, which contribute to a disease or disorder. For example, the pathology may be associated with a particular nucleic acid sequence, or "pathological nucleic acid" which refers to a nucleic acid sequence that contributes, wholly or in part to the pathology, as an example, the pathological nucleic acid may be a nucleic acid sequence encoding a gene with a particular pathology causing or pathology-associated mutation or polymorphism. The pathology may be associated with the expression of a pathological protein or pathological polypeptide that contributes, wholly or in part to the pathology associated with a particular disease or disorder. In another embodiment, the pathology is for example, associated with other factors, for example ischemia and the like.

[00119] As used herein, the term "treating" includes reducing or alleviating at least one adverse effect or symptom of a condition, disease or disorder.

[00120] The phrases "parenteral administration" and "administered parenterally" as used herein mean modes of administration other than enteral and topical administration, usually by injection, and includes, without limitation, intravenous, intramuscular, intraarterial, intrathecal,

intraventricular, intracapsular, intraorbital, intracardiac, intradermal, intraperitoneal, transtracheal, subcutaneous, subcuticular, intraarticular, sub capsular, subarachnoid, intraspinal, intracerebro spinal, and intrasternal injection and infusion. The phrases "systemic administration,"

"administered systemically", "peripheral administration" and "administered peripherally" as used herein mean the administration of PB-derived MSCs or BM-derived MSCs or differentiated progeny thereof and/or their progeny and/or compound and/or other material other than directly into the subject, such that it enters the animal's system and, thus, is subject to metabolism and other like processes, for example, subcutaneous or intravenous administration.

[00121] The phrase "pharmaceutically acceptable" is employed herein to refer to those

compounds, materials, compositions, and/or dosage forms w^rhich are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

[00122] The phrase "pharmaceutically acceptable carrier" as used herein means a

pharmaceutically acceptable material, composition or vehicle, such as a liquid or solid filler. diluent, excipient, solvent or encapsulating material, involved in carrying or transporting the subject agents from one organ, or portion of the body, to another organ, or portion of the body. Each carrier must be "acceptable" in the sense of being compatible with the other ingredients of the formulation.

[00123] The term "drug" or "compound" as used herein refers to a chemical entity or biological product, or combination of chemical entities or biological products, administered to a subject to treat or prevent or control a disease or condition. The chemical entity or biological product is preferably, but not necessarily a low molecular weight compound, but may also be a larger compound, for example, an oligomer of nucleic acids, amino acids, or carbohydrates including without limitation proteins, oligonucleotides, ribozymes, DNAzymes, glycoproteins, siRNAs, lipoproteins, aptamers, and modifications and combinations thereof.

[00124] The term "transplantation" as used herein refers to introduction of new cells (e.g. PB-derived MSCs or BM-derived MSCs or differentiated progeny thereof), or tissues (such as differentiated cells produced from PB-derived MSCs or BM-derived MSCs), or organs into a host (i.e. transplant recipient or transplant subject)

[00125] The term "modulate" is used consistently with its use in the art, e.g., meaning to cause or facilitate a qualitative or quantitative change, alteration, or modification in a process, pathway, or phenomenon of interest. Without limitation, such change may be an increase, decrease, or change in relative strength or activity of different components or branches of the process, pathway, or phenomenon. A "modulator" is an agent that causes or facilitates a qualitative or quantitative change, alteration, or modification in a process, pathway, or phenomenon of interest.

[00126] The terms "decrease", "reduced", "reduction", "decrease" or "inhibit" are all used herein generally to mean a decrease by a statistically significant amount. However, for avoidance of doubt, "reduced", "reduction" or "decrease" or "inhibit" means a decrease by at least 10% as compared to a reference level, for example a decrease by at least about 20%, or at least about 30%, or at least about 40%, or at least about 50%, or at least about 60%, or at least about 70%, or at least about 80%, or at least about 90% or up to and including a 100% decrease (e.g. absent level as compared to a reference sample), or any decrease between 10-100% as compared to a reference level.

[00127] The terms "increased" 'increase" or "enhance" or "activate" are all used herein to generally mean an increase by a statically significant amount; for the avoidance of any doubt, the terms "increased", "increase" or "enhance" or "activate" means an increase of at least 10% as compared to a reference level, for example an increase of at least about 20%, or at least about 30%, or at least about 40%, or at least about 50%, or at least about 60%, or at least about 70%, or at least about 80%, or at least about 90% or up to and including a 100% increase or any increase between 10- 100% as compared to a reference level, or at least about a 2-fold, or at least about a 3-fold, or at least about a 4-fold, or at least about a 5-fold or at least about a 10-fold increase, or any increase between 2-fold and 10-fold or greater as compared to a reference level.

[00128] The term "statistically significant" or "significantly" refers to statistical significance and generally means a two standard deviation (2SD) below normal, or lower, concentration of the marker. The term refers to statistical evidence that there is a difference. It is defined as the probability of making a decision to reject the null hypothesis when the null hypothesis is actually true. The decision is often made using the p-value.The term "substantially" as used herein means a proportion of at least about 60%, or preferably at least about 70% or at least about 80%, or at least about 90%, at least about 95%, at least about 97% or at least about 99% or more, or any interger between 70% and 100%

[00129] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus for example, references to "the method" includes one or more methods, and/or steps of the type described herein and/or which will become apparent to those persons skilled in the art upon reading this disclosure and so forth.

[00130] It is understood that the foregoing detailed description and the following examples are illustrative only and are not to be taken as limitations upon the scope of the invention. Various changes and modifications to the disclosed embodiments, which will be apparent to those of skill in the art, may be made without departing from the spirit and scope of the present invention. Further, all patents, patent applications, and publications identified are expressly incorporated herein by reference for the purpose of describing and disclosing, for example, the methodologies described in such publications that might be used in connection with the present invention. These publications are provided solely for their disclosure prior to the filing date of the present application. Nothing in this regard should be construed as an admission that the inventors are not entitled to antedate such disclosure by virtue of prior invention or for any other reason. All statements as to the date or representation as to the contents of these documents are based on the information available to the applicants and do not constitute any admission as to the correctness of the dates or contents of these documents. SC Mobilizing agents [00131] In one aspect of the invention, a method of treatment is provided comprising the administration to a mammal (e.g. a human) of an effective amount of a mobilizing agent, e.g. a form of G-CS F or GM-CSF and pharmaceutically acceptable salts thereof for enhancing

(stimulating) the production/release of MSCs as measured by phenotypic, physical or chemical properties or any other characteristics used by those skilled in the art to identify cells of a MSC type.

[00132] In one embodiment, the administration of a mobilizing agent such as GM-CSF or G-CSF which provides a peak number of circulating MSCs after about 2 daily injections. The peak in circulating MSCs the peripheral blood declines after at least 4 daily injections.

[00133] Any mesenchymal mobilizing agent, or combination of mesenchymal mobilizing agent can be administered to a subject for a set time for optimal mobilizing of MSCs into the peripheral blood. In some embodiments, the MSC mobilizing agent is GM-CSF or G-CSF (granulocyte colony stimulating factor). In some embodiments, other mobilizing agents can be administered to a subject include but are not limited to, G-CSF, GM-CSF, Flt-3 ligand, stem cell factor (SCF), dexamethazone, a CXCR4 receptors inhibitor, Interleukin- 1 (IL-1), Interleukin-3 (IL-3),

Diniplestim (IL-3 agonist), Leridistim (IL-3 agonist-G-CSF chimeric molecule), Progenipoietin-1 (Flt-3 ligand-G-CSF chimeric molecule), peg-filgrastim (NEULASTA™), Interleukin-8 (IL-8), PIXY-321 (GM-CSF/IL-3 fusion protein), macrophage inflammatory protein, stem cell factor (SCF), tlirombopoietin and growth related oncogene, as single mobilization agents or in any combination of such mobilizing agents. Other mobilizing agents include for example, but are not limited to CXCR4 inhibitors, such as AMD3100, ALX40-4C, T22, T134, T140 and TAK-779, which are disclosed in U.S. Pat. No. 7,169,750, which is incorporated herein by reference in its entirety.

[00134] In some embodiments, a mobilizing agent, such as G-CSF or GM-CSF, or interleukin-17 (IL- 17), AMD3100, cyclophosphamide (Cy) and Docetaxel (DXT), and combinations thereof can be administered to a subject or a peripheral blood sample ex vivo in an admixture to stimulate PB- derived MSCs.

[00135] In some embodiments, a mobilizing agent such as G-CSF or GM-CSF can be administered to a subject or a peripheral blood sample ex vivo in an admixture with additional active ingredients that are therapeutically or nutritionally useful, such as antibiotics, vitamins, herbal extracts, antiinflammatories, glucose, antipyretics, analgesics, granulocyte-macrophage colony stimulating factor (GM-CSF), Interleukin-1 (IL-1), Interleukin-3 (IL-3), Interleukin-8 (IL-8), PIXY-321 (GM- CSF/IL-3 fusion protein), macrophage inflammatory protein, stem cell factor, thrombopoietin, and the like.

[00136] Mobilized peripheral blood stem cell collections (PBSC) resulting from the use of a

mobilizing agent, e.g. G-CSF or GM-CSF can be transplanted into, e.g. a cancer patient. These can be either the total population of the mobilized white blood cells or purified HSCs obtained from the mobilized peripheral blood. HSCs are able to reconstitute the hematopoietic system of an organism, which requires self renewal of HSCs as well as differentiation to cells of the various hematopoietic lineages. The CD34 marker is characteristic of HSCs. Other cells that are mobilized using such mobilizing agents, which include polymorphonuclear white blood cells (cells that mediate inflammation and clearance of pathogens), mononuclear white blood cells (lymphocytes and monocytes) and red blood cell progenitors (erythroblasts).

[00137] Mobilization of CD34+ HSCs is a rapidly expanding clinical technique for obtaining material for autologous or allogenic hematopoietic transplantation. Furthermore, mobilization of polymorphs is a valuable adjunct to heavy chemotherapy to maintain innate defense mechanisms. Currently, both methods rely on mobilization by growth factors (G-CSF or GM-CSF) which is expensive, causes bone pain, and has unknown side effects for normal donors. It takes up to about 4 weeks of treatments to collect sufficient material for a transplant. After growth factor treatment, CD34+ cells reach a maximum level of 2-4% in blood.

G-CSF:

[00138] In some embodiments, G-CSF for use in the methods as disclosed herein can be prepared using recombinant methods and variants thereof may be used. The term G-CSF or G-CSF variant according to the present invention encompasses all naturally occurring variants of G-CSF, as well as G-CSF proteins derived therefrom, modified by recombinant DNA technology, particularly fused proteins containing other protein sequences in addition to the G-CSF portion. Particularly preferred in this meaning is a G-CSF mutein having an N-terminal Met residue at position 1 , which is suited for expression in prokaryotic cells. Similarly suitable is a recombinant G-CSF variant free of methionine which may be prepared according to WOA-91/11520, which is incorporated herein in its entirety by reference. The term "G-CSF variant" is understood to comprise those G-CSF molecules wherein one or more amino acids may be deleted or replaced by other amino acids, with the essential properties of G-CSF, particularly the ability to mobilize bone marrow cells, being largely retained. Suitable G-CSF muteins are described in EP0,456,200, for example, which is incorporated herein in its entirety by reference. [00139] In some embodiments, any commercially available form of G-CSF known to a skilled artisan can be used in the methods and compositions as disclosed herein, for example, but not limited to Neupogen®, (F. Hoffmann-La Roche Ltd., Basel, Switzerland) and variants thereof.

GM-CSF:

[00140] According to the present invention, GM-CSF (granulocyte-macrophage colony stimulating factor) prepared using recombinant methods and variants thereof may be used. The term GM -CSF or GM -CSF variant according to the present invention encompasses all naturally occurring variants of GM -CSF, as well as GM -CSF proteins derived therefrom, modified by recombinant DNA technology, particularly fused proteins containing other protein sequences in addition to the GM -CSF portion. Particularly preferred in this meaning is a GM -CSF mutein having an N- terminal Met residue at position 1, which is suited for expression in prokaryotic cells. Similarly suitable is a recombinant GM -CSF variant free of methionine which may be prepared according to WOA-91/1 1520, which is incorporated herein in its entirety by reference. The term " GM -CSF variant" is understood to comprise those G-CSF molecules wherein one or more amino acids may be deleted or replaced by other amino acids, with the essential properties of GM -CSF, particularly the ability to mobilize bone marrow cells, being largely retained. Suitable GM -CSF muteins are described in EP0,456,200, for example, which is incorporated herein in its entirety by reference.

[00141] Of the four 'granulocyte-macrophage' CSFs, GM-CSF was the first to be isolated and characterized. GM-CSF was shown to induce the proliferation of murine bone marrow— or spleen- derived haemopoietic cells containing granulocyte and macrophage progenitors giving rise to colonies containing mainly granulocyte and macrophage precursors. In this respect, GM-CSF appears to share biological properties with the subsequently characterized IL-3. However, more recent studies suggest that GM-CSF acts on 'later-stage' multipotential cells than IL-3. Also, GM- CSF appears to be less active than IL-3 in stimulating the proliferation of erythroid and

megakaryocyte precursors. Nevertheless, like IL-3, GM-CSF can be shown to have activities in mature cells of the granulocyte and macrophage lineages.

[00142] Without wishing to be bound by theory, GM-CSF (Granulocyte-Macrophage Colony

Stimulating Factor) acts directly and selectively on granulocyte/macrophage progenitors to stimulate growth and differentiation in vitro of cells belonging to these lineages, e.g. neutrophils, eosinophils, macrophages. These pleiotropic activities have also been demonstrated for recombinant GM-CSF. Besides regulation of the proliferation and differentiation of the progenitor/precursor cells of the myeloid lineage, GM-CSF has also been shown to activate the functions of mature myeloid cell types. For example, GM-CSF has been found to induce macrophage tumoricidal activity against the malignant melanoma cell line, A375. IFNy can also behave as a macrophage activating factor, but in contrast to GM-CSF requires an additional secondary stimulus, e.g. bacterial LPS, to evoke tumoricidal activity. In addition, GM-CSF activates macrophages to inhibit the replication of Trypanosoma cruzi (a unicellular parasite that is the aetiological agent of Chagas disease, or American trypanosomiasis) and increases respiratory oxidative processes. Furthermore, the replication of HIV- 1 in the human monocytic cell line U937 has been shown to be moderately inhibited by GM-CSF, and more effectively by the combination of GM-CSF and IFNy.

[00143] In neutrophils and eosinophils, GM-CSF stimulates a number of functions. In particular, GM- CSF enhances phagocytosis of bacteria and yeasts by neutrophils. Purified recombinant human GM-CSF has also been shown to enhance the cytotoxic activity of neutrophils and eosinophils against antibody-coated target cells.

[00144] It has been reported that when mice are repeatedly injected intraperitoneally with

recombinant murine GM-CSF, there is a rapid and sustained increase in the number and functional activity of peritoneal macrophages, granulocytes (neutrophils and eosinophils) as well as increased numbers of circulating monocytes. (GM-CSF usually takes about two weeks to act.) Marked increases in neutrophil, eosinophil, and monocyte numbers have also been observed following injection of recombinant human GM-CSF into AIDS patients and non-human primates. However, there may be complications associated with GM-CSF therapy. Metcalf and colleagues have shown that transgenic mice containing a constitutively expressed murine GM-CSF gene have pathological lesions soon after birth in various tissues, including lens, retina, and striated muscle, resulting from activated-macrophage infiltration. (Activated macrophages are known to produce a number of inflammatory mediators including cytokines such as TNFa and IL-1 which may induce tissue damage.)

[00145] In contrast to its growth-stimulating effects, GM-CSF can act as a differentiation factor. Its actions on mature macrophages and neutrophils, for example, might be considered as consequences of its differentiation-inducing capacity. One way to limit the proliferation of tumor cells is to decouple growth-factor-driven self-renewal from growth-factor-induced differentiation. In other words, the more 'differentiated' tumor cells become, the less able they are to multiply. In this regard, GM-CSF has been shown to induce differentiation of the myeloid leukaemic cell line HL60 and suppress its self-renew^ral. However, in several other studies, GM-CSF stimulated the proliferation of HL60 cells. Differentiation can be monitored by measuring expression of various plasma membrane-associated antigens, e.g. CD14 (monocyte/macrophage marker) and CD57 (NK cell marker).

[00146] In some embodiments, any commercially available form of GM-CSF known to a skilled artisan can be used in the methods and compositions as disclosed herein, for example, but not limited to Leucomax®, Schering Plough-Sandoz Pharma Ltd., Basel, Switzerland) and variants thereof.

Administration (Dose, duration, frequency, route (i.p, sc)

[00147] The dosage of G-CSF or GM-CSF may depend on various factors such as mode of

application, species, age, or individual condition. In some embodiments, the dose of G-CSF or GM-CSF is from about 100 to 700 μg/day of G-CSF or GM-CSF sub cutaneous (s.c.) is applied. The administration of G-CSF or GM-CSF is effected at least once per day over at least two days, or at least three days and no more than 4 days.

[00148] Different doses of G-CSF or GM-CSF include, but are not limited to about at least

100μ /(ΐ3ν, or at least about 200μg/day, or at least about 300μg/day, or at least about 400μg day, or at least about 500μg/day, or at least about 600μg/day, or at least about 700μg day, or more than 700μ^Λ^ of G-CSF or GM-CSF. In some embodiments, the dose does not exceed 1000μg/day over a period of 2 days. In some embodiments, the dose of G-CSF or GM-CSF is about 450μg/day for a duration of at least 1 day but less than 4 days. In some embodiments the dose of G-CSF or GM-CSF is about 400μg/day, or about 500μg/day for a duration of at least 1 days but less than 4 days. In some embodiments, the duration of dose of G-CSF is less than 5 days, and preferably less than 10μg/kg/day, or less than 7^g/kg/day, as these have been associated with severe side effects including increases in spleen length, headache, nausea, fatigue and bone pain, and in some cases spontaneous spleenic rupture (see review Cashen et ah, Bone marrow transplantation, 2007; 39; 577-588 and Pusic et al., Current Pharmaceutical Design, 2008; 14; 1950-1961, which are incorporated herein in their entirety by reference).

[00149] As disclosed herein, the inventors have demonstrated that a dose of 450 μ-g/day provided a major mobilization of PB-derived MSCs after at least 1 days of s.c. administration. Further, it wOuld be apparent to persons skilled in the art to try increasing or decreasing the doses of G-CSF or GM-CSF to find optimal doses for each use. This can be done simply by administering increasing doses of G-CSF or GM-CSF to subjects, and analyzing blood samples taken for example, as described herein. Furthermore, rather than, sequentially increasing the dose on a daily basis, the G-CSF or GM-CSF could be infused hourly (or at other intervals) at an optimal concentration which might be higher or lower than depending on the cells to be mobilized. Different frequencies and durations of G-CSF or GM-CSF administration can also be examined.

[00150] Suitable dosage ranges for G-CSF or GM-CSF vary according to these considerations, but in general, the compounds are administered in the range of about lOC^g/day, or at least about 20C^g/day, or at least about 300^ig/day, or at least about 400^ig/day, or at least about 50C^g/day, or at least about 60(^g/day, or at least about 700^ig/day, or more than 70(^g/day of G-CSF or GM- CSF. Dosages may be higher when the compounds are administered orally or transdermally as compared to, for example, i.v. administration.

[00151] For administration of G-CSF or GM-CSF to a subject as disclosed herein, the G-CSF or GM- CSF may be formulated for administration to an animal subject, such as a human using commonly understood formulation techniques well known in the art. Formulations which are suitable for particular modes of administration may be found in Remington's Pharmaceutical Sciences , latest edition, Mack Publishing Company, Easton, Pa.

[00152] In some embodiments, G-CSF or GM-CSF are administered to a subject, such as a human using standard administration forms, with injection solutions being preferred. Water is preferably used as injection medium which includes adjuvants common in injection solutions, such as stabilizers, solubilizers and buffers. For example, such adjuvants are tartrate and citrate buffers, ethanol, complexing agents such as ethylenediaminetetraacetic acid and the non-toxic salts thereof, high molecular weight polymers such as liquid polyethylene oxide for viscosity control. Liquid vehicles for injection solutions must be sterile and are preferably filled into ampoules.

[00153] Preferably, the G-CSF or GM-CSF are administered to a subject, such as a human by

injection, most preferably by intravenous injection, but also by subcutaneous or intraperitoneal injection, and the like. Additional parenteral routes of administration include intramuscular and intraarticular injection. For intravenous or parenteral administration, the G-CSF or GM-CSF can be formulated in suitable liquid form with excipients as required. The G-CSF or GM-CSF can be administered to a subject, such as a human subject in liposomes or other suitable carriers. For injection intravenously, the solution is made isotonic using standard preparations such as Hank's solution.

[00154] Besides injection, other routes of administration may also be used. In some embodiments, the G-CSF or GM-CSF to be administered to a subject, such as a human subject can be formulated into tablets, capsules, syrups, powders, or other suitable forms for administration orally. By using suitable excipients, the G-CSF or GM-CSF can be administered through the mucosa using suppositories or intranasal sprays. Transdermal administration can also be effected by using suitable penetrants and controlling the rate of release.

[00155] Different routes of administration of G-CSF or GM-CSF in addition to intravenous infusion are effective. For example, a "depot" of G-CSF or GM-CSF placed subcutaneously or

intraperitoneally would provide continuous infusion over a prolonged period and would be a convenient and effective method of providing G-CSF or GM-C SF. If G-CSF or GM-CSF is administered subcutaneously or intraperitoneally, for example continuous infusion could be achieved and monitoring of the subject over time. Alternatively, G-CSF or GM-CSF could be administered orally. The invention includes administration of G-CSF or GM-CSF by such means and all others as would be understood by persons skilled in the art.

[00156] Different protocols of G-CSF or GM-CSF administration including variations in G-CSF or GM-CSF dosage, route and duration of G-CSF or GM-CSF administration will mobilize different populations of stem cells, such as MSCs. As discussed above, the inventors have surprisingly discovered that the protocol for administration of GM-CSF and G-CSF for optimally mobilizing MSCs is different from one which is conventionally used for mobilizing HSCs. Thus, the protocol can be optimized for a particular desired application, by administering G-CSF or GM-CSF under different conditions, and then monitoring the output of the desired subset of stem cells, such as MSCs or hematopoietic cells in the blood according to the methods as disclosed herein. The time after infusion should be monitored for optimal recovery or induction of specific cell populations in the blood, because, as noted in the example herein, the appearance of different cell types occurred sequentially over a period of time following administration of the mobilizing agent.

[00157] The formulation and route of administration chosen will be tailored to the individual subject, the nature of the condition to be treated in the subject, and generally, the judgment of the attending practitioner.

[00158] In some embodiments, the G-CSF or GM-CSF can be administered to a subject, such as a human subject, as a single bolus dose, a dose over time, as in i.v. or transdermal administration, or in multiple dosages.

[00159] In addition to direct administration to the subject, the G-CSF or GM-CSF can be used in ex vivo treatment protocols to isolate MSCs from peripheral blood samples from a subject, which can be used to prepare MSC cultures which can be optionally cryopreserved and stored, and subsequently used, at a time when the MSCs are desired, for regenerative cell-based treatment of the subject. In some embodiments, this ex vivo generation of MSCs can be used to isolate and collect autologous MSCs harvested from the peripheral blood or in some circumstances, from allografts from matched donors. The concentration of the mobilizing agent contacting with the peripheral blood ex vivo, alone or in combination with other agents, such as macrophage inflammatory protein is a matter of routine optimization.

[00160] By administering G-CSF or GM-CSF, a massive granulopoiesis in the spleen and a

substantial increase of the spleen weight could be observed which, according to Bungart et al., Brit. J. Haem. 76, 174-179, 1990, is attributable to the stem cell mobilization or MSC mobilization.

[00161] In some embodiments, the peripheral blood sample which is used for the methods as

disclosed herein is obtained from a mammalian subject, such as a human subject. In some embodiments, the human subject has previously been administered a mobilizing agent to increase the yield or number of circulating stem cells in the peripheral blood. Any mobilizing agent can be used, such as according to methods commonly known in the art, and include, for example but are not limited to methods as disclosed in U.S. Patent Application 6,261,549 and U.S. Patent

Application 2009/0155225, which are incorporated herein by reference in their entirety.

[00162] In some embodiments, a mobilizing agent such as G-CSF or GM-CSF can be administered to a subject or a peripheral blood sample ex vivo in an admixture with any one or more additional mobilizing agents, e.g., an agent selected from the group consisting of interleukin-17 (IL-17), AMD3100, cyclophosphamide (Cy) and Docetaxel (DXT), and combinations thereof.

[00163] In some embodiments, a mobilizing agent such as G-CSF or GM-CSF can be administered to a subject or a peripheral blood sample ex vivo in an admixture with additional active ingredients that are therapeutically or nutritionally useful, such as antibiotics, vitamins, herbal extracts, antiinflammatories, glucose, antipyretics, analgesics, granulocyte-macrophage colony stimulating factor (GM-CSF), Interleukin-1 (IL-1), Interleukin-3 (IL-3), Interleukin-8 (IL-8), PIXY-321 (GM- CSF/IL-3 fusion protein), macrophage inflammatory protein, stem cell factor, thrombopoietin, and the like.

[00164] Any subject is amenable to MSCs mobilization using the methods as disclosed herein, and MSCs can be mobilized and collected from peripheral blood obtained from any subject, such as a human subject, including adult or a non-neonate child. Furthermore, MSCs can be collected at one or more collecting steps or collecting periods. For example, collection (e.g., using an apheresis process) of MSCs from mobilized peripheral blood may be performed at least two times, at least three times, or at least 5 times on a subject. During each collecting step, the number of total nucleated cells collected per kilogram weight of the person may be one million (1x10⁶) or more (e.g., 1 xlO⁷, 1 xlO⁸, lxlO⁹, IxlO¹⁰, lxlO¹⁵, lxlO¹², 1x10° lxlO¹⁴, lxlO⁵⁵, lxl0^!6, lxlO¹⁷, lxlO¹⁸, lxlO¹⁹, lxlO²⁰). In preferred embodiments, the number of cells in an apheresis product (which is used to separate the MSCs from non-MSCs) collected in a single collection session may be equal or greater than lxlO¹⁵, total nucleated cells (TNCs), or at least on the order of lxlO¹⁴, IxlO⁵³, IxlO¹², lxlO¹¹, lxlOⁱ⁰, lxlO⁹, lxlO⁸, lxlO⁷, lxlO⁶, lxlO⁵, total nucleated cells, depending on the weight and age of the donor subject.

[00165] Depending on the situation and MSCs can be obtained using the methods as disclosed herein from any human subject donor, it may be preferable to collect the stem cells from human subject donors when they are at an "adult" or a "matured" age (the term "adult" as used herein refers to and includes adult and non-neonate, unless otherwise used in a particular context to take a different meaning) and/or at a certain minimum weight. For example, MSCs can be collected when the subject is within a range from 10 to 200 kg in accordance with one embodiment of the present invention, or any range within such range, such as 20 to 40 kg. In addition or in the alternative, it may be required that the subject be of a certain age, within a range from 2-80 years old (e.g., 2-10, 10-15, 12-18, 16-20, 20-26, 26-30, 30-35, 30-40, 40-45, 40-50, 55-60, 60-65, 60-70, and 70-80 years old) in accordance with one embodiment of the present invention.

Isolation and separation of MSCs from other stem cells populations in the peripheral blood

[00166] Methods to obtain and isolate the PB-derived MSCs and BM-derived MSG from peripheral blood are well known in the art, and include leucopheresis, density gradient fractionation, immunoselection and differential adhesion separation. The substantially pure population of MSCs can be collected in media or culture media, such as for example a chemically defined serum free media or a complete medium, such as DMEM or DMEM-1 g containing serum. Suitable chemically defined serum free media are described in U.S. Ser. No. 08/464,599, filed Jun. 5, 1995, and "complete media" are described in U.S. Pat. No. 5,486,359, issued Jan. 23, 1996, which is incorporated herein by reference.

[00167] One aspect of the present invention is to separate MSCs from the mobilized peripheral blood using centrifugal elutriation. Without wishing to be bound by theory, in one method of elutriation, a peripheral blood sample is introduced into a generally funnel-shaped separation chamber located on a spinning centrifuge. A flow of liquid elutriation buffer or low density liquid is then introduced into the chamber containing the peripheral blood sample. As the flow rate of the liquid elutriation buffer solution is increased through the chamber (usually in a stepwise manner), the liquid sweeps smaller sized, slower-sedimenting cells toward an elutriation boundary within the chamber, while larger, faster-sedimenting cells migrate to an area of the chamber where the centrifugal force and the sedimentation (drag) forces are balanced. Accordingly, as the peripheral blood, e.g. mobilized peripheral blood, comprises many different populations of stem cells, one aspect of the present invention relates to the separation of these different stem cell populations present in peripheral blood into distinct populations using elutriation, where smaller stem cells are fractionated from stem cells which are larger in size.

[00168] In some aspects of the present invention, any elutriation device can be used to obtain and isolate the PB-derived MSCs and BM-derived MSC from other stem cell populations in the peripheral blood. In some embodiments, the elutriation device uses an apheresis product (where platelets and blood cells are returned to the subject donor) and the remaining peripheral blood product is the apheresis product is elutriated at a certain flow rate to fractionate a peripheral blood sample into a fraction which comprises a population of MSCs. In some embodiments,

commercially available elutriation devices can be used to separate MSCs from peripheral blood, for example, the ELUTRA® centrifuge manufactured by Gambro BCT, Inc. The ELUTRA CELL SEPARATION SYSTEM® enables the separation of mobilized peripheral blood into a fraction comprising MSCs using both size and density, enabling cell enrichment, depletion, concentration, and washing all within a functionally-closed system. The ELUTRA CELL SEPARATION

SYSTEM® enables enrichment of stem cell populations directly from leukapheresis products without antibodies or preprocessing in less than one hour. The Elutra Cell Separation System® uses counter-flow centrifugal elutriation, where fluid flows through cell layers in a centrifugal field in order to separate cell populations.

[00169] In some embodiments, other elutriation devices can be used to separate MSCs from

peripheral blood, including but not limited to, the COBE® Spectra apheresis system, the Trima® system and the Trima Accel® system, also manufactured by Gambro BTC Inc., as well as other commercially available elutriation devices used to separate blood components.

[00170] In some embodiments, a population of MSCs can be obtained from a mobilized peripheral blood sample using a cell separator such as the COBE® Spectra Apheresis System. The COBE® SPECTRA™ centrifuge is described in U.S. Patents 4,425,172, 4,708,712, and 6,022,306, which are incorporated herein by reference. In such an embodiment, the mobilized peripheral blood sample (or apheresis product obtained from a subject w^rho has been administered a mobilizing agent according to the methods as disclosed herein) is drawn into a cell separator such as the COBE Spectra Apheresis System, and optionally, an anticoagulant solution is added to the blood to keep it from clotting during the procedure. The blood/anticoagulant admixture cycles through a centrifuge to separate the peripheral blood sample into a MSC populations and mononuclear cells from the other blood components and plasma. The system pumps the separated MSCs into a collection bag for storage, while the other blood components and lasma return to the patient. All tubing sets and needles used are sterile, so there is no risk of disease transmission.

[00171] Other blood-separation apparatus, such as the apparatus described in U.S. Pat. No. 5,722,926, issued Mar. 3, 1998; U.S. Pat. No. 5,951,877, issued Sep. 14, 1999; U.S. Pat. No. 6,053,856, issued Apr. 25, 2000; U.S. Pat. No. 6,334,842, issued Jan. 1 , 2002; U.S. patent application Ser. No.

10/884,877 filed Jul. 1, 2004; U.S. Pat. 7,201,848, U.S. Patent 6,022,306, U.S. Patent 6,589,526, U.S. Patent Applications 2008/0035585, US2008/0318756 and 2009/0104626 can be used, the entire disclosure of each of these U.S. patents and patent applications is incorporated herein by reference.

[00172] The inventors have discovered that hematocrit ranges employed for apheresis can be

advantageously adjusted to enhance properties of the collected cell population. For example, in one embodiment, the hematocrit range is selected to enhance the proportion of VSELs. In another embodiment, the hematocrit range is selected to enhance cryopreservation of collected VSELs, for example by minimizing collection of granulocytes. In another embodiment, the hematocrit range is selected to ensure simultaneous collection of multiple stem cell populations, such as, for example, VSELs and MSCs. In one embodiment, the hematocrit range is selected to be 2-3%. In another embodiment, the hematocrit range is selected to be 3-4%.

Identification of MSC

[00173] MSCs can be identified by FACs sorting, as well as immunos election and phenotypic analysis using light microscopy and CFU-F assay, as disclosed herein. By way of an example only, light- microscopic examination can be performed on Wright-Giemsa stained cells either in the culture plate or in cytospin preparations of EDTA-detached cells. Histochemical staining can be performed by standard protocols using diagnostic kits (Sigma) for Sudan Black, Periodic Acid-Schiff (PAS), a-naphthyl butyrate esterase, acid phosphatase and alkaline phosphatase.

[00174] For immunofluorescence studies, MSCs can be processed with a fixation/permeabilization reagent (Cytoperm®, Serotech Ltd., Oxford, England) and labeled with appropriate free or FITC- conjugated monoclonal antibodies (as discussed herein) and detected under ultraviolet illumination at 50 nm with a mercury gas lamp on a Nikon microscope.

[00175] For flow cytometric analysis, EDTA-released MSCs or MSCs in the apheresis products can be stained with either pure or FITC- or PE -conjugated monoclonal antibodies. Nonspecific isotype- matched antibodies can be used to determine background fluorescence. MSCs can be analyzed on a FACScan flow cytometer (Becton Dickinson, BD) and data acquisition can be performed with a FACScan Lysis II (BD) research software, according to procedures commonly known in the art.

[00176] The following monoclonal antibodies can be used to detect MSCs: anti CD-45-FITC, anti- CD14-PE, anti-CD34-PE, (Becton Dickinson); anti collagen I, anti collagen III and anti fibronectin (Sigma); anti collagen VI (Gibco BRL, Grand Island, N.Y., USA); anti ICAM-1 (CD54) and anti VCAM-1 (CD106) (R&D Systems, Minneapolis, Minn., USA). Control mouse IgG 1 -PE, IgG 1 - FITC, IgG 2a -PE and F(ab') 2 -PE (Becton Dickinson). Monoclonal antibodies SH-2 (IgG 1 ) and SH-3 (IgG 2b ) (Case Western Reserve University, Cleveland, Ohio., USA or Osiris Therapeutics, Inc. (Baltimore, Md., USA). These antibodies recognize antigens on the cell surface of MSCs, but fail to react with BM-derived HSCs as well as with the cell surface of osteoblasts or osteocytes.

[00177] Any collected sample of a substantially pure population of MSC may be tested for the total cell count and cell viability by Trypan blue via dye exclusion. Samples of a substantially pure population of MSC may also be analyzed for the presence of cells expressing cell markers.

[00178] The total cell count and cell viability of pre-processing, post-processing, and any other sample of cells may be quantified by a hand count with a hemocytometer, a flow cytometer, or other means suitable for obtaining cell count, such as, for example, ViCell (Beckman Coulter) or software suitable to count cells displayed on a microscopic image.

Cryopreservation

[00179] In some embodiments, the substantially pure population of human MSCs obtained by the methods as disclosed herein can be cryopreserved (e.g. frozen) at liquid nitrogen temperatures and stored for long periods of time, being capable of use on thawing. If frozen, the MSCs will usually be stored in a 10% DMSO, 50% FCS, 40% RPMI 1640 medium. Once thawed, the human MSCs can be cultured and expanded ex vivo in the presence of growth factors and'Or feeder layers for an appropriate period of time prior to implanting into a subject in need thereof.

[00180] Methods of cryopreservation of stem cells, such as MSCs are commonly known by one of ordinary skill in the art, and are disclosed in U.S. Patent Applications 2008/0220520,

2009/0022693, 2008/0241 113 and 2005/0106554 and U.S. Patents 5,759,764 and 7, 112,576 and 7,604,930.

[00181] For cryopreservation, the substantially pure population of MSCs obtained by the methods as disclosed herein, can be suspended in DPBS may be placed on ice for at least about 15 minutes in preparation for cryopreservation. The preparation may comprise adding cryopreservation media to the substantially pure population of MSCs and then subjecting the mixture to several temperature reduction steps to reduce the temperature of the substantially pure population of MSCs to a final temperature of about -90° C. utilizing a controlled rate freezer or other suitable freezer system (dump-freeze monitored or a freeze container (Nalgene)). Suitable control rate freezers include, but are not limited to, Cryomed Thermo Form a Controlled Rate Freezer 7454 (Thermo Electron, Corp.), Planar Controlled Rate Freezer Kryo 10/16 (TS Scientific), Gordinier, Bio-Cool— FTS Systems, and Asymptote EF600, BIOSTOR CBS 2100 series.

[00182] Cryopreservation media may be prepared comprising media and DMSO. About 3 ml of

DPBS may be added to a container, such as, for example, a 50 ml conical tube. About 1 ml of Human Serum Albumin (HSA) may be added to the about 3 ml of DPBS and then chilled for about ten minutes on ice. About 1 ml of the chilled 99% DMSO is added to the HSA and DPBS to prepare the final cryopreservation media. Cryopreservation media and the substantially pure population of MSCs sample may then be placed on ice for about 15 minutes before the

cryopreservation media is added to the cell sample. Batch processing may be used for aliquoting cryopreservation media into a cell sample. For example, a single aliquot of about 100 ul of substantially pure population of MSC suspension may be combined with about 3 ml of DPBS, 1 ml of HSA, and about 1 ml of 99% DMSO. About 2 aliquots of about 200 ul of MSC cell suspension may be combined with about 6 ml of DPBS, 2 ml of HSA, and about 2 ml of 99% DMSO. About 5 aliquots of cell sample may be combined with about 15 ml of DPBS, about 5 ml of HSA, and about 5 ml of 99% DMSO. About 10 aliquots of cell sample may be combined with about 30 ml of DPBS, about 10 ml of HSA, and about 10 ml of 99% DMSO.

[00183] In an alternative embodiment, other cryopreservation media may be used. For example, cryopreservation media with cryopreservation agents may be used to maintain a high cell viability outcome post-thaw, such as, for example, CryoStor CS10 or CSS (Biolife), embryonic

cryopreservation media supplemented with propanediol and sucrose (Vitrolife), or SAGE media (Cooper Surgical). Glycerol may be used with other cryopreservation agents, such as, DMSO, or may be used alone at a concentration of about 10% in a media with suitable protein.

[00184] Cryopreservation media may be added to the substantially pure population of MSC cell sample. Cryopreservation media may be added to a substantially pure population of MSCs suspended in DPBS drop by drop until the volume of total mixture of suspended menstrual stem cells and cryopreservation media is brought to the final desired volume of cryopreservation cell mixture. The final cryopreservation cell media may be transferred into 2x5 ml bar-coded cryoquats with the QC sample stored in the cap of the 5 ml vial. Use a pipettor to remove about 200 μΐ aliquots of the sample and aliquot into the QC caps. After the caps have been filled, add the remaining 4.8 ml of specimen into the 5 ml vial. Samples should be sent for infectious disease and other analysis. The cryo vials should be placed in the CRYOMED Freezer and subject to temperature reduction by controlled rate to a temperature at or below about -85° C, The cryopreserved specimens should be transferred to a bunker for storage in the vapor of Liquid Nitrogen at -150° C. or less. Any sample that tests positive for an infectious disease should be quarantined. Any sample that tests negative for infectious disease may be transferred to a different permanent storage.

[00185] The following temperature reduction steps may be programmed in the controlled rate freezer, first reducing the mixture of cryopreservation agent and menstrual stem cells. The menstrual stem cells combined with cryopreservation agent may be subjected to controlled rate temperature reductions in preparation for final storage in a freezer. The controlled rate reductions may be designed to maintain cell viability. A Cryo-Med Freezer (Thermo Electron Corp.), liquid nitrogen cylinder, and portable Cryo-Med Freezer may be used for controlled rate reductions in preparation for final storage in freezer. The cells may be subject to controlled rate reductions in cryovials or cryobags to reach a temperature of about -90° C.

[00186] For a sample of substantially pure population of MSCs collected in a cryobag, the cells may be subject to the following controlled rate reduction profile: wait at about 4° C, 1.0° C. per minute to -6.0° C. (sample), 25.0° C. per minute to -50.0° C. (chamber), 10.0° C. per minute to -14.0° C. (chamber), 1.0° C. per minute to -45.0° C. (chamber), 10.0° C. per minute to -90.0° C. (chamber), and end (sample at or below -85.0° C).

[00187] For a sample of substantially pure population of MSCs collected in a cryovial, the cells may be subject to the following controlled rate reduction profile: wait at 4.0° C, 1.0° C. per minute to - 3.0° C. (chamber), 10.0° C. per minute to -20.0° C. (chamber), 1.0° C. per minute to -40.0° C. (chamber), 10.0° C. per minute to -90.0° C. (chamber), and end.

[00188] Once the mixture of cryopreservation agent and menstrual stem cells is at or below about -85° C, the cryopreservation vials are transferred to a cryogenic storage unit and stored in the vapor of liquid Nitrogen at a temperature at or below about -135° C. or alternatively vials may be stored in the liquid phase of liquid nitrogen. For example, a suitable cryogenic storage unit includes, but is not limited to, LN2 Freezer MVE 1830 (Chart Industries).

[00189] Fresh samples of substantially pure population of MSC and thawed samples of substantially pure population of MSC that were previously cryopreserved may also be analyzed by flow cytometry to analyze cell surface markers, cell viability, and other cell characteristics. Fresh samples of a substantially pure population of MSC may also be analyzed according to the following protocol after cell lysis.

[00190] Cryopreserved MSCs must be thawed according to the thawing process described herein. In cases where a MSC cell sample must be thawed, the substantially pure population of MSC may require flow cytometry analysis immediately after thaw or after cells are cultured to assess a certain cell passage. The cryopreserved samples may be agitated in a 37° C. water bath without letting the cells completely thaw. The cells may be transferred into about 1 ml of chilled wash media and mixed by inversion. The sample may be centrifuged at about 2000 rpm for about seven minutes. The supernatant may be removed and the cells resuspended in about 100 ul of wash media (25% HSA, DNAse, Heparin and HBSS w/Ca+ and Mg+). The resuspended cells may then be centrifuged in a Blood Bank Serofuge for about 1 minute. The supernatant may be decanted and the cells resuspended in about 1.2 ml Sheath fluid and vortexed.

[00191] Also within the scope of the present invention is moderate to long-term storage of all or part of the human MSCs obtained by the methods as disclosed herein, such as moderate or long-term storage in a cell bank. Such moderate to long term storage of cell in a cell bank is disclosed in U.S. Patent Application Serial No. 2003/0054331 and Patent Application No. WO03/024215, and is incorporated by reference in their entireties. At the end of processing, the human MSCs as disclosed herein may be loaded into a delivery device, such as a syringe, for placement into the recipient subject by any means known to one of ordinary skill in the art.

[00192] In some embodiments, a human MSCs obtained by the methods as disclosed herein can optionally be packaged in a suitable container, in the presence of an suitable media. In some embodiments, the package further comprises written instructions for a desired purpose, such as methods of implantation into a subject (and optionally methods of storage and/or methods of thawing if cryopreserved) of the human MSCs for the improvement or treatment of a disease, or for a treatment protocol for regenerative medicine or therapy.

Methods of Treatment

[00193] One aspect as disclosed herein relates to a method for the treatment of a subject in need of increased numbers of stem cells, such as MSCs. In some embodiments, the subject is scheduled to or intends to donate stem cells such as MSCs, e.g., for use in heterologous or autologous transplantation. Generally, the methods include administering a therapeutically effective amount of the mobilizing agent, such as GM-CSF or G-CSF as described herein, to a subject wito is in need of, or who has been determined to be in need of, such treatment. Administration of a therapeutically effective amount of a mobilizing agent, such as G-CSF of GM-CSF as described herein for at least 2 days, or at least 3 days but no more than 4 days, for the treatment of such subjects will result in an increased number and/or frequency of MSCs in the peripheral blood. In some embodiments, such administration will result in an increase of about 10-500-fold in the number of MSCs in the peripheral blood. Methods of measuring such increases are known in the art, which are disclosed herein, and see, e.g., Neben et al., Blood. 1993; 81(7): 1960-7; Ashihara et al. Exp. Hematol. 2000; 28(3):311-7; Pruijt et al., Proc. Natl. Acad. Sci. U.S.A. 1999;

96(19): 10863-8.

[00194] Dosage, toxicity and therapeutic efficacy of the mobilizing agent, such as G-CSF or GM-CSF can be determined by standard pharmaceutical procedures, e.g., in cell cultures or experimental animals, e.g., for determining the LD50 (the dose lethal to 50% of the population) and the ED50 (the dose therapeutically effective in 50% of the population). The dose ratio between toxic and therapeutic effects is the therapeutic index and it can be expressed as the ratio LD50/ED50.

Mobilizing agents, such as G-CSF of GM-CSF that exhibit high therapeutic indices are preferred. While compounds that exhibit toxic side effects may be used, care should be taken to design a delivery system that targets such compounds to the site of affected tissue in order to minimize potential damage to uninfected cells and, thereby, reduce side effects.

[00195] The data obtained from the cell culture assays and animal studies can be used in formulating a range of dosage for use in humans. The dosage of such compounds lies preferably within a range of circulating concentrations that include the ED50 with little or no toxicity. The dosage may vary within this range depending upon the dosage form employed and the route of administration utilized. For any compound used in the method of the invention, the therapeutically effective dose can be estimated initially from cell culture assays. A dose may be formulated in animal models to achieve a circulating plasma concentration range that includes the IC50 (i.e., the concentration of the test compound that achieves a half-maximal inhibition of symptoms) as determined in cell culture. Such information can be used to more accurately determine useful doses in humans.

Levels in plasma may be measured, for example, by high performance liquid chromatography.

[00196] According to another aspect of the invention, a method is provided to mobilize MSCs from one tissue to another, as a single agent or before/during other clinical procedures. These cells include non-hematopoietic normal cells and have the potential during at least one differentiation stage in their life cycle to undergo mobilization/migration in vivo.

[00197] According to another aspect of the invention a method is provided to mobilize MSCs before and during harvesting of tissue to be used for organ transplantations by the infusion of effective amounts of a mobilizing agent such as GM-CSF or G-CSF. In some embodiments, the present invention also provides a method to use an ex vivo mobilizing agent such as GM-CSF or G-CSF to mobilize MSCs out of an ex vivo organ or peripheral blood sample that has already been harvested from a subject. This includes, for example, the in vivo perfusion of peripheral blood from a legally dead organ donor in vivo prior to harvesting the PB-derived or BM-derived MSCs from the subject.

[00198] In one embodiment, an effective amount of a mobilizing agent, such as G-CSF or GM-CSF is administered to a subject for the mobilization of BM-derived MSCs in the peripheral blood of the subject. In another embodiment, an effective amount of a mobilizing agent, such as G-CSF or GM- CSF is administered to a subject for the mobilization of PB-derived MSCs in the peripheral blood of the subject. In another embodiment, an effective amount of a mobilizing agent, such as G-CSF or GM-CSF is contacted with a peripheral blood sample from the subject for the mobilization of PB-derived MSCs in the peripheral blood ex vivo. An "effective amount" is an amount sufficient to effect a significant increase in the number and/or frequency of MSCs in the peripheral blood. An effective amount can be administered in one or more administrations, applications or dosages. A therapeutically effective amount of a mobilizing agent depends on the mobilizing agent selected, e.g. G-CSF or GM-CSF. The mobilizing agent, such as G-CSF or GM-CSF can be administered one from one or more times per day to one or more times per week; including once every other day. The skilled artisan will appreciate that certain factors may influence the dosage and timing required to effectively treat a subject, including but not limited to previous treatments, the general health and/or age of the subject, and other diseases present. Moreover, treatment of a subject with a therapeutically effective amount of the G-CSF or GM-CSF as described herein can include a single treatment or a series of treatments.

[00199] In some embodiments, the methods of treatment described herein include administering another mobilizing agent, e.g., an agent selected from the group consisting of, but not limited to, interleukin-17 (IL-17; Journal of Immunol. 2001 ; 167: 2081-2086), AMD3100 (Flomenberg et al., Acta Haematol. 2005; 114(4): 198-205), cyclophosphamide (Cy), Docetaxel and (DXT) (Ojeifo et al. Experimental Hematology 2000; 28:451-459).

[00200] In some embodiments, the methods include administering the PB-derived MSCs or BM- derived MSCs, or their differentiated progeny to a subject, e.g., reintroducing the cells into the same subject or transplanting the cells into a second subject, e.g., an HLA type-matched second subject.

[00201] In some embodiments, subjects that can usefully be treated using the PB-derived MSCs or BM-derived MSCs include any subjects who can be normally treated with a bone marrow or stem cell transplant, e.g, subjects who have cancers, e.g., neuroblastoma (cancer that arises in immature nerve cells and affects mostly infants and children), myelodysplasia, myelofibrosis, breast cancer, renal cell carcinoma, or multiple myeloma. For example, the PB-derived MSCs or BM-derived MSCs can be transplanted into subjects who have cancers that are resistant to treatment with radiation therapy or chemotherapy, e.g., to restore stem cells that were destroyed by high doses of chemotherapy and/or radiation therapy used to treat the cancers.

[00202] In some embodiments, the MSCs may then be centrifuged in a Blood Bank Serofuge for about 1 minute. The supernatant may be decanted and the cells resuspended in about 1.2 ml Sheath fluid and vortexed.

[00203] Also within the scope of the present invention is moderate to long-term storage of all or part of the MSC population, or a substantially pure population of MSCs obtained by the methods as disclosed herein, such as moderate or long-term storage in a cell bank. Such moderate to long term storage of cells in a cell bank is disclosed in U.S. Patent Application Serial No. 2003/0054331 and Patent Application No. WO03/024215, and is incorporated by reference in their entireties. At the end of processing, the MSCs population, or a substantially pure population of MSCs as disclosed herein may be loaded into a delivery device, such as a syringe, for placement into the recipient subject by any means known to one of ordinary skill in the art. In some embodiments, a MSC population obtained using the methods as disclosed herein can be suspended in a short term storage medium suitable for infusion into a subject, such as the media disclosed in US Patent 5,955,257, which is incorporated herein in its entirety by reference. In some embodiments, the MSCs which are collected and enriched using the methods as disclosed herein can be stored (e.g. for future therapeutic use by the donor (e.g. allogenic) or by another subject) or directly transplanted, e.g. for use to promote post-surgical healing.

[00204] In one aspect of the invention, the plurality of MSCs collected by the methods as disclosed herein can be further sorted into at least two subpopulations which may be cryopreserved separately or together (e.g., in the same vial). In some embodiments, at least two subpopulations of MSCs may be two different subpopulation of MSCs. For example, MSCs can be sorted into at least two subpopulation of cells, for example, but not limited to (1) a stem cell population or a population enriched for MSCs and (2) a non stem cell population or a population depleted for MSCs. Furthermore, it is also envisioned that the two subpopulations (i.e., (1) and (2) above) may be cryopreserved together. In some embodiments, this sorting of MSCs into subpopulations can be by positive or negative sorting, or a combination thereof. [00205] In some embodiments, markers of cell surface proteins can be used to positively select for or negatively select or remove stem cells. Examples of such markers are well known in the art, and are shown in Table 1 :

[00206] In some embodiments, a MSC population, or a substantially pure population of MSCs obtained by the methods as disclosed herein can optionally be packaged in a suitable container, in the presence of an suitable media. In some embodiments, the package further comprises written instructions for a desired purpose, such as methods of implantation into a subject (and optionally methods of storage and/or methods of thawing if cryopreserved) of the MSCs, or a substantially pure population of MSCs for the improvement or treatment of a disease, or for a treatment protocol for regenerative medicine or therapy.

MSCs for autologous cellular therapy:

[00207] In one embodiment of the present invention, the MSCs collected from the mobilized

peripheral blood of a subject by the methods as disclosed herein can be introduced or transplanted back to the individual when the subject is in need of such cellular therapy (e.g. autologous cell therapy). In some embodiments, the MSCs can be used either alone or in combination with other cells, for future autologous therapeutic applications in regenerative therapy, such as wound healing, cardiac repair and bone repair and other orthopedic indications, as disclosed herein in the

Examples. In some embodiments, the MSCs collected from the mobilized peripheral blood of a subject by the methods as disclosed herein can be used for repair or treatment of eye diseases, such as retinopathy or macular degeneration, as discussed in Vossmerbaeumer et al., Cytotherap , 2009; 1 1; 177-188, which is incorporated herein in its entirety by reference. In some embodiments, the MSCs collected from the mobilized peripheral blood of a subject by the methods as disclosed herein can be differentiated into anv number of different cell tvDes of mesoderm ori-∑in. including adipocytes, osteoblasts and chrondrocytes, as discussed in Musina et al.. Cell Technologies in Biology and Medicine, 2006: 2; 147-151. which is incorporated herein in its entirety by reference. Methods for implantation of the MSCs for treatment of cardiovascular disorders and other disorders are well known to one of ordinary skill in the art, and are disclosed in International Patent WO 2008/054819, and US Patent 6,387,369, 7514074, 6,174,333 and 6,225,1 19 and US Patent Application 2009/0214493 which are incorporated herein in their entirety by reference.

[00208] In an embodiment of the invention, the MSCs obtained from an individuals mobilized peripheral blood may be used for personalized medicine applications, such as autologous therapeutic use, as well as in a personalized assay to assess the effect of a persons diet,

phamacogenetics, neutrochemicals, lifestyle on the function and viability of MSCs.

[00209] A MSCs composition comprising a portion or all of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be used to repair, treat, or ameliorate various aesthetic or functional conditions (e.g. defects) through the augmentation of damage tissues. The MSCs collected from the peripheral blood of a subject by the methods as disclosed herein provide an important resource for rebuilding or augmenting damaged tissues. In one embodiment, the MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be used in tissue engineering and regenerative medicine for the replacement of body parts that have been damaged by developmental defects, injury, disease, or the wear and tear of aging. The MSCs populations collected from the peripheral blood of a subject by the methods as disclosed herein provide a unique system in which the MSCs can be differentiated into different cells and to give rise to specific lineages of the same individual or genotypes. The MSCs collected from the peripheral blood of a subject by the methods as disclosed herein therefore provide significant advantages for individualized stem cell therapy.

[00210] In addition, such MSCs collected from the peripheral blood of a subject by the methods as disclosed herein and compositions thereof can be used for augmenting soft tissue not associated with injury by adding bulk to a soft tissue area, opening, depression, or void in the absence of disease or trauma, such as for "smoothing". Multiple and successive administrations of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein are also embraced by the present invention.

[00211] For stem cell-based treatments, a MSG populations collected from the peripheral blood of a subject by the methods as disclosed herein are preferably collected from an autologous source. MSCs compositions are then prepared and isolated as described herein, and in particular, isolated from other stem cell populations present in mobilized peripheral blood. To introduce or transplant MSCs collected from the peripheral blood of a subject by the methods as disclosed herein and/or compositions thereof according to the present invention into a human or animal recipient, a suspension of mononucleated cells is prepared. The mononucleated cell suspensions contain concentrations of MSCs, and can be separated from other stem cells present in the peripheral blood and the MSCs collected and resuspended in a physiologically-acceptable carrier, excipient, or diluent. Alternatively, MSC suspensions may be in serum-free, sterile solutions, such as cryopreservation solutions. In some embodiments, a preparation enriched in MSCs may also be used. In some embodiments, the MSC suspensions may then be introduced e.g., via injection, into one or more sites of the donor tissue.

[00212] Concentrated or enriched stem cells may be administered as a pharmaceutically or

physiologically acceptable preparation or composition containing a physiologically acceptable carrier, excipient, or diluent, and administered to the tissues of the recipient organism of interest, including humans and non-human animals. The MSCs-containing composition may be prepared by resuspending the cells in a suitable liquid or solution such as sterile physiological saline or other physiologically acceptable injectable aqueous liquids. The amounts of the components to be used in such compositions can be routinely determined by those having skill in the art.

[00213] In some embodiments, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein or compositions thereof may be administered by placement of the stem cell suspensions onto absorbent or adherent material, i.e., a collagen sponge matrix, and insertion of the MSC-containing material into or onto the site of interest. Alternatively, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein may be administered by parenteral routes of injection, including subcutaneous, intravenous, intramuscular, and intrasternal. Other modes of administration include, but are not limited to, intranasal, intrathecal, intracutaneous, percutaneous, enteral, and sublingual. In one embodiment, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed can be administered by endoscopic surgery.

[00214] For injectable administration, a composition comprising a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be suspended in sterile solution or suspension or may be resuspended in pharmaceutically- and physiologically-acceptable aqueous or oleaginous vehicles, which may contain preservatives, stabilizers, and material for rendering the solution or suspension isotonic with body fluids (i.e. blood) of the recipient. Non- limiting examples of excipients suitable for use include water, phosphate buffered saline, pH 7.4, 0.15 M aqueous sodium chloride solution, dextrose, glycerol, dilute ethanol, and the like, and mixtures thereof. Illustrative stabilizers are polyethylene glycol, proteins, saccharides, amino acids, inorganic acids, and organic acids, which may be used either on their own or as admixtures. The amounts or quantities, as well as the routes of administration used, are determined on an individual basis, and correspond to the amounts used in similar types of applications or indications known to those of skill in the art.

[00215] Consistent with the present invention, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be administered to body tissues, including epithelial tissue (i.e., skin, lumen, etc.) muscle tissue (i.e. smooth muscle), blood, brain, and various organ tissues such as those organs that are associated with the urological system (i.e., bladder, urethra, ureter, kidneys, etc.).

[00216] According to the general treatment method described herein, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can comprise other cells, (e.g. a fraction of cells comprising a target stem cell population) can be administered to a subject, for example, by infusion into the blood stream of a subject through an intravenous (i.v.) catheter, like any other i.v. fluid. Alternatively, however, an individualized mixture of MSC populations may be generated such as to provide a cellular therapy mixture specific for therapeutic needs of a subject. The comprehensive mixture of cells obtained such as through an apheresis process may be characterized, sorted, and segregated into distinct cell populations. Cell markers such as VSELs, MSC and HSC markers or tissue specific markers may be used to phenotypically characterize the populations of cells collected from the peripheral blood. Using these markers, it is possible to segregate and sort on the basis of cell type. The mixture of cells is thus transformed into populations of cells, which may be broadly classified into two portions: a stem cell portion and a non-stem cell portion. The non-stem cell portion may further be classified into a progenitor cell or fibroblast portion and a function cell or fully differentiated cell portion. Once the peripheral blood cellular mixture is sorted, the population of MSCs and non-stem cell portions may be

cryopreserved and stored separately. In this manner, a library or repository of distinct cell populations from a subject may be created. Alternatively, a population of MSCs and non-stem cell portions may the cryopreserved together and then sorted and separated prior to use.

[00217] In some embodiments, the population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be used to generate or differentiate into any population of a cell type that developed from a germ layer (i.e., endoderm, mesoderm, and ectoderm). These include, but are not limited to differentiated cells, neural progenitor or differentiated cells, glial progenitor or differentiated cells, oligodendrocyte progenitor or differentiated cells, skin progenitor or differentiated cells, hepatic progenitor or differentiated cells, muscle progenitor or differentiated cells, bone progenitor or differentiated cells, mesenchymal stem or progenitor cells, pancreatic progenitor or differentiated cells, progenitor or differentiated chondrocytes, stromal progenitor or differentiated cells, cultured expanded stem or progenitor cells, cultured differentiated stem or progenitor cells, or combinations thereof. Also of interest are progenitor cells, such as hematopoietic, neural, stromal, muscle (including smooth muscle), hepatic, pulmonary, gastrointestinal, and mesenchymal progenitor cells. Also of interest are a population of MSCs which have differentiated, such as differentiation into cells, such as but not limited to osteoblasts, hepatocytes, granulocytes, chondrocytes, myocytes, adipocytes, neuronal cells, pancreatic, or combinations and mixtures thereof.

[00218] In some embodiments, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein can be combined, recombined, or compounded into a cellular therapy mixture of cells appropriate for treating the disease of a subject and/or regenerating a specific tissue. A combination of a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein, with tissue specific progenitor cells, and optionally functional cells can be used, for example to enhance the engraftment of the transplanted MSCs.

[00219] Accordingly, in one embodiment, the present invention provides methods and products for using an autol ogous mixture of population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein. This population of MCSs can be used alone, or combined with other useful cells. In some embodiments, the MSCs can be combined with other stem cells obtained from the peripheral blood, or other functionally useful non-stem cells.

[00220] Accordingly, a subjects MSCs can be used alone, or selectively recombined (e.g. custom mixing) for individualized autologous therapeutic applications in regenerative therapy. Stated another way, a population of autologous MSCs can be selectively combined with other cells, including stem cells, such as other non-MSC stem cells obtained from the peripheral blood for an autologous cellular therapy. In some embodiments, a mixed population of MSCs can comprise from about 10% to about 90% of a MSCs collected from the peripheral blood of a subject by the methods as disclosed herein, about 10% to about 80%, or about 10% to about 60%, or about 10% to about 40%, or about 10% to about 90% of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein. In some embodiments, a population of MSCs can also comprise a population of non-stem cells (e.g. functional cells) and/or stem cells which are not MSCs which are also obtained from peripheral blood, such as from about 5% to about 50% or functional cells and/or non-MSCs stem cells, about 5% to about 40% or functional cells and/or non-MSCs stem cells, about 5% to about 30% or functional cells and/or non-MSCs stem cells, about 5% to about 20% of or functional cells and/or non-MSCs stem cells, or about 5% to about 10% or functional cells and/or non-MSCs stem cells.

[00221] A suitable example of the cellular therapy product described above is the autologous mixture of HSCs and MSCs or other functional cell of the hematopoietic system. Another example is a cellular therapy product comprising a population of autologous MSCs in an mixture with other cells, such as at least one or any combination of the following cell types: HSCs, PBSCs, myocardial progenitor cells, and optionally myocardial cells.

[00222] Accordingly, in another embodiment, there is provided a method of treating a patient in need thereof comprising administering to a subject an autologous mixture of population of MSCs, either alone or in combination (either separately or in an admixture) collected from the peripheral blood of a subject by the methods as disclosed herein.

Stem Cell Banking

[00223] In another aspect of the present invention, a population of MSCs collected from the

peripheral blood of a subject by the methods as disclosed herein can be stored in a cell bank to support an elective healthcare insurance model to effectively protect members of the population from future diseases. An individual subject can elect to have his or her ow^rn stem cell populations collected from the peripheral blood, processed and preserved, while he or she is in healthy state, for future distribution for his or her healthcare needs.

[00224] Accordingly, in one embodiment, a population of MSCs collected from the peripheral blood of a subject by the methods as disclosed herein are "banked" for future use, at a stem cell bank or depository or storage facility, or any place where the target stem cell populations are kept for safekeeping. The storage facility may be designed in such a way that the target stem cell populations collected from the peripheral blood of a subject by the methods as disclosed herein are kept safe in the event of a catastrophic event such as a nuclear attack. In some embodiments, the storage facility might be underground, in caves or in silos. In other embodiments, it may be on the side of a mountain or in outer space. The storage facility may be encased in a shielding material such as lead.

[00225] According to another embodiment, there is provided a process of stem cell banking with four steps. Step A involves administrating one or more mobilizing agents to a subject to increase the amount of the population of MSCs in the peripheral blood of the subject. Step B involves collecting a population of MSCs from the peripheral blood by the methods as disclosed herein, wherein said subject has no immediate perceived health condition, e.g. no condition where the subject is requiring treatment using his autologous transplantation of their own target stem cell populations. Step C involves preserving the population of MSCs collected from the peripheral blood by the methods as disclosed herein as a preserved populations of cells. Step D involves retrieving the preserved population of MSCs collected by the methods as disclosed herein cells for autologous transplantation of the population of MSCs into the subject.

[00226] Reference will be made in detail to the embodiments of the invention, examples of which are illustrated in some of the accompanying drawings. In some embodiments of the present invention includes isolation of MSC from mobilized blood, using an Elutra® centrifuge manufactured by Gambro BCT, Inc. of Lakewood, Colorado. Although embodiments of this invention are described in combination with the Elutra® centrifuge, this reference is made for exemplary purposes only and is not intended to limit the invention in any sense. It is understood that other centrifuges could be used with embodiments of the invention, including but not limited to, the COBE® Spectra apheresis system, the Trima® system and the Trima Accel® system, also manufactured by Gambro BTC Inc., as well as other elutriation devices used to separate blood components.

Use of MSCs for personalized Medicine diagnostic and prognostic assays.

[00227] Another aspect of the present invention relates to the use of the MSCs obtained from an individuals mobilized peripheral blood for personalized medicine applications, such as autologous therapeutic use, as well as in a personalized assay to assess the effect of a persons diet,

phamacogenetics, neutrochemicals, lifestyle on the function and viability of MSCs. Such assays are currently well known in the art, and include high throughput screens where a compound, agent, or environmental stimuli is contacted with a MSC, and the effect of the compound, agent or environmental stimuli on the function (e.g. differentiation potential, propagation, survival) and viability of the MSCs can be measured, and the result compared to a reference control sample (e.g. in the absence of a compound, or a positive control sample, such as the presence of BMP6 and the like).

[00228] In one aspect of the present invention, a population of MSCs obtained from a subject can be used in a high-throughput screen to assess the subjects individual response to the agent, such as to a particular drug, hormone treatment or medicine or therapy. Briefly, a MSC population of cells are contacted with the agent of interest, and the effect of the agent assessed by monitoring output parameters, such as expression of markers, cell viability, differentiation characteristics. multipotenticy capacity and the like. The MSCs may be freshly isolated using the methods as disclosed herein, or in some embodiments, cultured, cryopreserved, or genetically engineered prior to using in an assay. In some embodiments, the subject's MSCs can be environmentally induced variants of clonal cultures: e.g. split into independent cultures and grown under distinct conditions, for example with or without virus; in the presence or absence of other cytokines or combinations thereof.

[00229] Importantly, as the MSCs are specific to the subjects genetic make-up, the use of the MSCs provide a tool for pharmcogenetic analysis of the MSCs. For example, a subject's MSCs may harbor a particular variant which results in a distinct pathological characteristic. For example, as the MSCs are from the subject (e.g. autologous) they have a desired pathological characteristic, e.g. mutation and/or polymorphism which contribute to disease pathology, or result in a poor or enhanced response to a therapeutic drug. Therefore the MSCs obtained by the methods as disclosed herein can be used to assess the subject's MSC response to a particular compound, agent, and in some cases this may be useful for prognosis for a disease. In such an embodiment, the methods of the invention can be used to screen for agents which alleviate the pathology, or agents which positively affect the propagation or function of the MSCs.

[00230] In alternative embodiments, the methods of the invention can be used to screen for agents which cause a different response on the subject's MSCs (due to an inherent genetic make up or a particular mutation and/or polymorphism) as compared with MSCs from other subjects (e.g.

without the mutation and/or polymorphism), therefore the methods can be used for example, to assess an effect of a particular drug and/or agent on subjects MSC population as compared to other people and/or MSC cells, therefore acting as a high-throughput screen for personalized medicine and/or pharmogenetics. The manner in which the MSCs respond to an agent, particularly a pharmacologic agent, including the timing of responses, is an important reflection of the physiologic state of the cell.

[00231] Parameters are quantifiable components of MSCs, particularly components that can be accurately measured, desirably in a high throughput system. A parameter can be any cell component or cell product including cell surface determinant, receptor, protein or conformational or posttranslational modification thereof, lipid, carbohydrate, organic or inorganic molecule, nucleic acid, e.g. mRNA, DNA, etc. or a portion derived from such a cell component or

combinations thereof. While most parameters will provide a quantitative readout, in some instances a semi-quantitative or qualitative result will be acceptable. Readouts may include a single determined value, or may include mean, median value or the variance, etc. Characteristically a range of parameter readout values will be obtained for each parameter from a multiplicity of the same assays. Variability is expected and a range of values for each of the set of test parameters will be obtained using standard statistical methods with a common statistical method used to provide single values.

[00232] Compounds, including candidate agents, are obtained from a wide variety of sources

including libraries of synthetic or natural compounds. For example, numerous means are available for random and directed synthesis of a wide variety of organic compounds, including biomolecules, including expression of randomized oligonucleotides and oligopeptides. Alternatively, libraries of natural compounds in the form of bacterial, fungal, plant and animal extracts are available or readily produced. Additionally, natural or synthetically produced libraries and compounds are readily modified through conventional chemical, physical and biochemical means, and may be used to produce combinatorial libraries. Known pharmacological agents may be subjected to directed or random chemical modifications, such as acylation, alkylation, esterification,

amidification, etc. to produce staictural analogs.

[00233] Agents are screened for effect on the stem cell population by adding the agent to at least one and usually a plurality of stem cell samples, usually in conjunction with cells lacking the agent. The change in parameters in response to the agent is measured, and the result evaluated by comparison to reference cultures, e.g. in the presence and absence of the agent, obtained with other agents, etc.

[00234] In some embodiments, the agents are conveniently added in solution, or readily soluble form, to the medium of stem cells in culture. The agents may be added in a flow-through system, as a stream, intermittent or continuous, or alternatively, adding a bolus of the compound, singly or incrementally, to an otherwise static solution. In a flow-through system, two fluids are used, where one is a physiologically neutral solution, and the other is the same solution with the test compound added. The first fluid is passed over the stem cells, followed by the second. In a single solution method, a bolus of the test compound is added to the volume of medium surrounding the cells. The overall concentrations of the components of the culture medium should not change significantly with the addition of the bolus, or between the two solutions in a flow through method. In some embodiments, agent formulations do not include additional components, such as preservatives, that may have a significant effect on the overall formulation. Thus preferred formulations consist essentially of a biologically active compound and a physiologically acceptable carrier, e.g. water, ethanol, DMSO, etc. However, if a compound is liquid without a solvent, the formulation may consist essentially of the compound itself. [00235] A plurality of assays may be run in parallel with different agent concentrations to obtain a differential response to the various concentrations. As known in the art, determining the effective concentration of an agent typically uses a range of concentrations resulting from 1 : 10, or other log scale, dilutions. The concentrations may be further refined with a second series of dilutions, if necessary. Typically, one of these concentrations serves as a negative control, i.e. at zero concentration or below the level of detection of the agent or at or below the concentration of agent that does not give a detectable change in the phenotype.

[00236] Optionally, the subjects MSCs used in the screen can be manipulated to express desired gene products, e.g. to give the MSCs a desired physiological characteristic and/or to repair or replace an undesirable mutation and/or polymorphism in the genetic make-up of the MSC. Accordingly, such gene therapy would be done on the subject's MSCs ex vivo prior to autologous transplantation back into the subject. In some embodiments, the MSCs can be genetically modified to replace a gene product or add or knockdown a gene product. In some embodiments the genetic engineering is done to facilitate regeneration of tissue, to treat disease, or to improve survival of the MSCs following implantation into a subject (i.e. prevent rejection). Techniques for transfecting cells are known in the art.

[00237] A skilled artisan could envision a multitude of genes which would convey beneficial properties to the transfected subjects mesenchymal cells if the stem cell is used for the purposes of autologous transplantation. In some embodiments, the added gene may ultimately remain in the recipient MSC and all its progeny, or may only remain transiently, depending on the gene and the embodiment. For example, genes encoding angiogenic factors could be transfected into MSCs isolated from peripheral blood. Such genes would be useful for inducing collateral blood vessel formation as the MSCs are used in differentiating into cardiomvocvtes and for the repair of cardiac muscle. It some situations, it may be desirable to transfect the cell with more than one gene.

[00238] In some instances, it is desirable to have the gene product secreted. In such cases, the gene product preferably contains a secretory signal sequence that facilitates secretion of the protein. For example, if the desired gene product is an angiogenic protein, a skilled artisan could either select an angiogenic protein with a native signal sequence, e.g. VEGF, or can modify the gene product to contain such a sequence using routine genetic manipulation (See Nabel et al, 1993).

[00239] In one embodiment of the invention, the MSCs obtained from an individuals mobilized peripheral blood can be used as an individualized assay for the study and understanding of signaling pathways of the subjects MSCs growth and differentiation. The use of the subject's MSCs of the present invention is useful to aid the development of therapeutic applications for congenital and adult heart failure. The use of such subject's MSCs of the invention enable the study of specific differentiation into different lineages, e.g. osteogenic lineages, cardiac lineages without the need and complexity of time consuming animal models. In another embodiment, the subject's MSCs can be genetically modified to carry specific disease and/or pathological traits and phenotypes of a particular disease or disorder.

[00240] In one embodiment, the assay comprises a plurality of the subject's MSCs of the invention, or their differentiated progeny. In one embodiment, the assay can be used for the study of

differentiation pathways of a subject's MSCs, for example but not limited to the differentiation along the cardiomyocyte lineage, smooth muscle lineage, endothelial lineage, and subpopulations of these lineages.

[00241] In another embodiment, the assay can be used to study a pathological characteristic of the subject's MSCs, for example, a disease and/or genetic characteristic associated with a disease or disorder. In some embodiments, the disease of disorder is a wound healing disorder, bone disorder or a cardiovascular disorder or disease. In some embodiments, the subject's MSCs has been genetically engineered to comprise the characteristic associated with a disease or disorder. Such methods to genetically engineer the subject's MSCs are well known by those in the art, and include introducing nucleic acids into the cell by means of transfection, for example but not limited to use of viral vectors or by other means known in the art.

[00242] In some embodiments, the subject's MSCs can be easily manipulated in experimental systems that offer the advantages of targeted lineage differentiation as well as clonal homogeneity and the ability to manipulate external environments. Furthermore, due to ethical unacceptability of experimentally altering a human germ line, the ES cell transgenic route is not available for experiments that involve the manipulation of human genes. Gene targeting in human subject's MSCs of the present invention allows important applications in areas where the system cannot be tested in vivo due to ethical issues, and can adequately recapitulate human biology or disease processes for that particular subject or individial.

[00243] In another embodiment, the subject's MSCs of this invention can be used to prepare a cDNA library relatively uncontaminated with cDNA that is preferentially expressed in cells from other lineages.

[00244] The subject's MSCs of this invention can also be used to prepare antibodies that are specific for markers of cardiomyocytes and their precursors. Polyclonal antibodies can be prepared by injecting a vertebrate animal with cells of this invention in an immunogenic form. Production of monoclonal antibodies is described in such standard references as U.S. Pat. Nos. 4,491,632, 4,472,500 and 4,444,887, and Methods in Enzymology 73B:3 ( 1981). Specific antibody molecules can also be produced by contacting a library of immunocompetent cells or viral particles with the target antigen, and growing out positively selected clones. See Marks et al., New Eng. J. Med. 335:730, 1996, and McGuiness et al, Nature Biotechnol. 14: 1449, 1996. A further alternative is reassembly of random DNA fragments into antibody encoding regions, as described in EP patent application 1,094,108 A.

[00245] The antibodies in turn can be used to identify or rescue (for example restore the phenotype) cells of a desired phenotype from a mixed cell population, for purposes such as costaining during immunodiagnosis using tissue samples, and isolating precursor cells from terminally differentiated subject's MSCs and cells of other lineages.

[00246] In another embodiment, the subject's MSCs can be used to examine of the gene expression profile during and following differentiation of the subject's MSCs of the invention. The expressed set of genes may be compared against other subsets of MSCs from a different subjects or control MSC sample as known in the art. Any suitable qualitative or quantitative methods known in the art for detecting specific mRNAs can be used. mRNA can be detected by, for example, hybridization to a microarray, in situ hybridization in tissue sections, by reverse transcriptase-PCR, or in

Northern blots containing poly A+ mRNA. One of skill in the art can readily use these methods to determine differences in the molecular size or amount of mRNA transcripts between two samples.

[00247] Any suitable method for detecting and comparing mRNA expression levels in a sample can be used in connection with the methods of the invention. For example, mRNA expression levels in a sample can be determined by generation of a library of expressed sequence tags (ESTs) from a sample. Enumeration of the relative representation of ESTs within the library can be used to approximate the relative representation of a gene transcript within the starting sample. The results of EST analysis of a test sample can then be compared to EST analysis of a reference sample to determine the relative expression levels of a selected polynucleotide, particularly a polynucleotide corresponding to one or more of the differentially expressed genes described herein.

[00248] Alternatively, gene expression in a test sample can be performed using serial analysis of gene expression (SAGE) methodology (Velculescu et al., Science (1995) 270:484). In short, SAGE involves the isolation of short unique sequence tags from a specific location within each transcript. The sequence tags are concatenated, cloned, and sequenced. The frequency of particular transcripts within the starting sample is reflected by the number of times the associated sequence tag is encountered with the sequence population. [00249] Gene expression in a test sample can also be analyzed using differential display (DD) methodology. In DD, fragments defined by specific sequence delimiters (e.g., restriction enzyme sites) are used as unique identifiers of genes, coupled with information about fragment length or fragment location within the expressed gene. The relative representation of an expressed gene with a sample can then be estimated based on the relative representation of the fragment associated with that gene within the pool of all possible fragments. Methods and compositions for carrying out DD are well known in the art, see, e.g., U.S. Pat. No. 5,776,683; and U.S. Pat. No. 5,807,680.

Alternatively, gene expression in a sample using hybridization analysis, which is based on the specificity of nucleotide interactions. Oligonucleotides or cDNA can be used to selectively identify or capture DNA or RNA of specific sequence composition, and the amount of RNA or cDNA hybridized to a known capture sequence determined qualitatively or quantitatively, to provide information about the relative representation of a particular message within the pool of cellular messages in a sample. Hybridization analysis can be designed to allow for concurrent screening of the relative expression of hundreds to thousands of genes by using, for example, array-based technologies having high density formats, including filters, microscope slides, or microchips, or solution-based technologies that use spectroscopic analysis (e.g., mass spectrometry). One exemplary use of arrays in the diagnostic methods of the invention is described below in more detail.

[00250] Hybridization to arrays may be performed, where the arrays can be produced according to any suitable methods known in the art. For example, methods of producing large arrays of

oligonucleotides are described in U.S. Pat. No. 5,134,854, and U.S. Pat. No. 5,445,934 using light- directed synthesis techniques. Using a computer controlled system, a heterogeneous array of monomers is converted, through simultaneous coupling at a number of reaction sites, into a heterogeneous array of polymers. Alternatively, microarrays are generated by deposition of pre- synthesized oligonucleotides onto a solid substrate, for example as described in PCT published application no. WO 95/35505. Methods for collection of data from hybridization of samples with an array are also well known in the art. For example, the polynucleotides of the cell samples can be generated using a detectable fluorescent label, and hybridization of the polynucleotides in the samples detected by scanning the microarrays for the presence of the detectable label. Methods and devices for detecting fluorescently marked targets on devices are known in the art. Generally, such detection devices include a microscope and light source for directing light at a substrate. A photon counter detects fluorescence from the substrate, while an x-y translation stage varies the location of the substrate. A confocal detection device that can be used in the subject methods is described in U.S. Pat. No. 5,631 ,734. A scanning laser microscope is described in Shalon et al.. Genome Res. (1996) 6:639. A scan, using the appropriate excitation line, is performed for each fluorophore used. The digital images generated from the scan are then combined for subsequent analysis. For any particular array element, the ratio of the fluorescent signal from one sample is compared to the fluorescent signal from another sample, and the relative signal intensity determined. Methods for analyzing the data collected from hybridization arrays are well known in the art. For example, where detection of hybridization involves a fluorescent label, data analysis can include the steps of determining fluorescent intensity as a function of substrate position from the data collected, removing outliers, i.e. data deviating from a predetermined statistical distribution, and calculating the relative binding affinity of the targets from the remaining data. The resulting data can be displayed as an image with the intensity in each region varying according to the binding affinity between targets and probes. Pattern matching can be performed manually, or can be performed using a computer program. Methods for preparation of substrate matrices (e.g., arrays), design of oligonucleotides for use with such matrices, labeling of probes, hybridization conditions, scanning of hybridized matrices, and analysis of patterns generated, including comparison analysis, are described in, for example, U.S. Pat. No. 5,800,992. General methods in molecular and cellular biochemistry can also be found in such standard textbooks as Molecular Cloning: A Laboratory Manual, 3rd Ed. (Sambrook et al., Harbor Laboratory Press 2001); Short Protocols in Molecular Biology, 4th Ed. (Ausubel et al. eds., John Wiley & Sons 1999); Protein Methods (Bollag et al, John Wiley & Sons 1996); Nonviral Vectors for Gene Therapy (Wagner et al. eds., Academic Press 1999); Viral Vectors (Kaplift & Loewy eds., Academic Press 1995); Immunology Methods Manual (I. Lefkovits ed., Academic Press 1997); and Cell and Tissue Culture: Laboratory Procedures in Biotechnology (Doyle & Griffiths, John Wiley & Sons 1998). Reagents, cloning vectors, and kits for genetic manipulation referred to in this disclosure are available from commercial vendors such as BioRad, Stratagene, Invitrogen, Sigma-Aldrich, and ClonTech.

EXAMPLES

[00251] METHODS

[00252] Apheresis procedure. All subjects receive subcutaneous injections of G-CSF (Neupogen) 480 μg for at least 2 days or less than 4 days or a single dose of AMD3100 (Plerixafor, Mozobil®, Genzyme Corporation, Cambridge, MA) 240 prior to cell administration to mobilize stem cells and will undergo apheresis on the day after administration. Prior to undergoing apheresis, a peripheral blood sample will be drawn (Days 1, 2, 3, 4, and 5) to monitor white blood cell count (WBC) and FACS analysis performed on Days 4 and 5 to assess mobilization efficacy of CD34+ cells in the circulation as well as determine apheresis parameters. In the event that the subject's WBC is elevated > 60,000 mm \ delivery of G-CSF will be discontinued and the apheresis be performed as early as possible. Apheresis will be performed at the New York Blood Center at Beth Israel Medical Center, Petrie Division (see attached letter of support. Dr. Vijay Shah, Medical Director).

[00253] MSC isolation and expansion. The apheresis product of all the subjects will be processed as described below to isolate MSC for cell therapy according to standard techniques.

[00254] The various cell populations in the mobilized PB will be separated by Ficoll-Paque followed by gradient centrifugation in 50 ml conical tubes. Layer 20 ml of PB onto each 10 ml of Ficoll- Paque liquid that is already aliquoted in to 50 ml tubes. This is accomplished by slowly and gently allowing the PB to flow down the side of the tube onto the fluid. Centrifuge the layered tubes at room temperature at 400 x g for 30 minutes. Once the PB has been centrifuged, the middle buffy coat layer is placed into T25 culture flasks. 7 ml of MSC complete media will be used per T25 flask. Twice a week cells are checked by light microscopy for contamination and cell morphology, and media will be changed. Non-adherent cells will be washed while changing the medium. After cells become confluent, they will be passaged to T75 flasks. For cell therapy to patient, early passages (up to 5) will be used. Quality control testing including phenotypic characterization, karyotyping, mycoplasma and bacterial testing will be conducted on the final cell product prior to cell delivery to the patient. Cell dose will be 1,000,000 cells.

[00255] Preparation of Autologous Cultured MSC. Remove media from the T-75 flasks. Wash each flask with 10 ml of IX sterile PBS for 2 minutes. Remove the PBS and add 1.2 ml of Trypsin- EDTA to each flask. Rotate the flasks so that the trypsin completely coats the bottom of each flask. Return the flasks to the incubator for 10 minutes. Check for proper trypsinization by checking for rounding of cells and cell mobility. Inactivate the Trypsin-EDTA by adding 5 ml of MSC media to each flask. Using a pipette, gently w^rash the media back and forth across the bottom of the flask to maximize cell capture. Use the same pipette to transfer the cell /media mixture to a centrifuge tube. Combine the cells and media from all of the flasks into one 50 ml centrifuge tube. Centrifuge the cells for 7 minutes at 400 g (1400 rpm) at room temperature. Carefully remove the supernatant and resuspend the cell pellet in 10 ml of sterile normal saline (standard 0.9% normal saline obtained from pharmacy). Centrifuge the cells for 7 minutes at 400 g (1400 rpm) at room temperature.

Repeat this procedure 2 times. Carefully remove the supernatant and count the cells by suspending them in 1.5 ml of saline and taking a small aliquot of this for a 1 to 10 dilution (ΙΟμΙ in 100 μΐ of media). The hemacytometer well requires ΙΟμΙ of fluid sample.

[00256] Administration to a subject for treatment of wound healing: The MSCs will then be mixed with the fibrin gel as described below and applied to the wound three times at an interval of 4 weeks.

[00257] Preparation and Application of Diluted Fibrin Gel/ Cell mixture. The following are

instructions to make a diluted fibrin gel utilizing a 1 ml TISSEEL VH kit (Baxter Healthcare, Inc.) This kit utilizes two liquid phases that can be either extruded through a dual chamber applicator or sprayed through the applicator with an inert gas carrier. In this dilute fibrin gel, the final concentrations of sealer protein and thrombin are 25 units/ml, respectively.

[00258] A sterile mixture of 30 mM calcium (CaC_i2) in normal saline (0.9% NaCl) is made by adding 0.22 lg of CaCi₂ powder to 50 ml of sterile normal saline and filtering the mixture through a 0.22 μΐΉ tube -top filter under the tissue culture hood. To make up the thrombin solution, 1 ml bottle of thrombin is dissolved in the heating mixer for 20 min. Once this mixture is dissolved, 0.5 ml out from the bottle is drawn with a syringe and mixed with 4.5 ml of the sterile CaCli mixture. This mixture is kept warm in the heating mixer. This diluted thrombin solution is used within 4 hours of the initial dissolving step. To make up the sealer protein, using a 1 ml syringe, 1 ml of sterile normal saline is added to the sealer protein bottle and allowed to dissolve in the heater mixer for 20 min. Once this mixture is dissolved, 0.5 ml from the bottle is drawn with a syringe and mixed with 4.5 ml of sterile normal saline. This mixture is kept warm in the heating mixer. This diluted sealer protein is used within 4 hours of the initial dissolving step. Form the gel by: First decide on the total amount of gel to be applied depending on the size of the wound. Each of the two liquids will be half of this total amount. In a 1 ml pipette, draw up the same amount of sealer protein as will be required for the final volume of sealer protein/cell mixture. Mix the cells and the sealer protein by gently pipetting up and down in the centrifuge tube (4 times) that the cells were in. Draw up the sealer protein/cell mixture into a 1 ml syringe insuring that bubbles are removed. Into another 1 ml syringe, draw up the same volume of thrombin solution as there is of sealer protein/cell mixture; again, tap out any bubbles. Remove the needles and snap both syringes into the red applicator. Then place the white/clear applicator top over the opening of the syringes. For spraying, attach the sterile gas hose to the applicator top and keep the gas supply flowing for the duration of the application to prevent clotting in the applicator top. If the gel will be extruded, rather than sprayed, continue steady, slow extrusion until all of the fluid is used up to avoid clotting in the applicator tip. [00259] CFU-C Test (Colony-Forming Units Culture)

[00260] The femoral bone marrow cell number was adjusted to 2.5 ^χ cells/ml in MEM (flow). 0.2 ml of this suspension was mixed with 0.5 ml of horse serum, 0.1 ml of thioglycerol (20 mM, diluted 1 :4 with MEM), 1.0 ml of methylcellulose (2% in MEM), 0.6 ml of MEM (flow), and 0.1 ml of either additional medium or standardized stimulated mouse serum (1 :200 dilution of serum, withdrawn 3 hours after ip. administration of 2.5 mg/kg lipopolysaccharide (LPS)) or 5 ng/ml rhG- CSF. The well-mixed semi-solid suspension was pipetted into Petri dishes 4 cm in diameter and incubated for 6 days at 37° C, 5% CO 2 and 95% r.h.. After addition of 0.5 ml of p- iodonitrotetrazolium violet solution (0.5 mg/ml PBS), the dishes were incubated for another 24 hours. The colonies were counted using a colony counter and standardized to 10 6 bone marrow cells.

EXAMPLE 1

[00261] Isolation and expansion of MSCsfi'om peripheral blood

[00262] The inventors utilized MSCs derived from mobilized peripheral blood where Granulocyte Colony Stimulating Factor (G-CSF) was administered to a subject to mobilize MSCs from Bone Marrow to the peripheral circulation. The mobilized peripheral blood will be enriched for stem cells by Ficoll-separation and collection of buffy coat that contains mononuclear cells. The cells from the buffy coat are then plated in cell culture flasks with MSC growth medium. The nonadherent cells will be washed away during the regular (every 3-days) media changes in the first two weeks. The adherent cells will then be expanded in MSC growth medium up to 5 passages.

[00263] Evidence that MSC are mobilized into peripheral blood by G-CSF

[00264] The present inventors have demonstrated that MSCs were mobilized into peripheral blood of healthy subjects in response to two successive subcutaneous injections of G-CSF (480 μg per day). In this experiment, the inventors demonstrate that in pre-mobilized and mobilized peripheral blood samples analyzed by multi-parametric flow cytometric analysis, there is an enrichment of the number of cells that express MSC phenotype i.e. CD45-, CD34-, CD105+, CD90+, CD29+. Figure 6 shows significant increase in the numbers of MSC in peripheral blood of healthy human donors (n=5) following G-CSF mobilization. A one-tailed paired T-test has shown that MSCs that are CD45-, CD34-, CD90+, CD105+, CD29+, responded well to G-CSF mobilization and the number of MSC post-mobilization sample are significantly increased (p=0.03) compared to the pre- mobilization sample.

[00265] Use of MSC samples obtained from mobilized peripheral blood [00266] Chronic ischemic, diabetic and venous stasis wounds affect millions of Americans and are responsible for a great deal of morbidity including loss of function, chronic pain syndromes, and increased risk of systemic, even fatal infections. The resistance to cure in cutaneous wounds, even when underlying conditions have been ameliorated, may relate to senescence of cells, particularly of "in-tissue" stem cells within the wounds, abnormal, disease-based responses to the normative cell-cell and cell-matrix signaling present in successful wound healing, or to necrotic debris and/or scar which create coarse and microscopic tissue disruptions that prevent circulating humoral or cellular contributions to the healing process. In particular, systemic cell trafficking of bone marrow -derived stem cells may play an important role in wound healing and such endogenous barriers to engraftment may be important. Use of humans autologous, bone marrow-derived (not peripheral blood derived), mesenchymal stem cells (MSCs) have been isolated from patients with chronic wounds, cultured ex vivo, and applied to the wound achieved significant functional tissue restoration of all tissue layers of the affected limb with a minimum of scar formation. Accordingly, one aspect of the present invention relates to the use of PB-derived MSCs obtained from subjects according to the methods as disclosed herein, the MSCs can be obtained from subject that have more easily accessible, circulating MSCs, mobilized from bone marrow, where the subjects have been administered granulocyte-colony stimulating factor and obtained from peripheral blood.

Accordingly, such an approach would be a significant advance over the prior studies that isolated cells directly from patient's marrow, a procedure that can be laborious, painful and costly and in some cases not practical. The inventors have demonstrated procedures to isolate and capture MSCs from blood making the procedure to obtain MSCs for wound healing simpler and in fact allows the possibility to collect and store stem cells prior to injury for later use. Accordingly, the inventors demonstrate that application of cultured, autologous, circulating MSCs directly to chronic, nonhealing cutaneous wounds can accomplish significant improvement or complete wound healing with reconstitution of function and minimal scar formation. _G-CSF induced mobilization of MSCs from the bone marrow^r into peripheral circulation will be followed by apheresis to isolate MSCs. MSCs will be grown in culture, passaged up to 5 times, and then applied to wounds topically (in a fibrin mixture) at 3 time points with an interval of 4-weeks between each time point.

[00267] MSC Samples to be Banked for Future Investigations. It is likely if MSCs are used in the repair and healing of wounds, not all wounds will heal to the same extent. Determining underlying conditions in each patient which may predispose to or inhibit wound healing would be useful.

Accordingly, MSCs can be banked for future analysis. Possible anticipated adjunct studies include, but are not limited to, comparative quantitative analyses of pre- and post-mobilization circulating MSC populations, serum cytokines and chemokines of interest (either individually, by ELISA, or through comprehensive proteomics screen), immunohistochemical and in situ hybridization analysis of cells and diffusible factors in punch biopsies from wounds over time for markers of differentiation, activation, proliferation, and apoptosis. The inventors can use the MSCs to prospectively sample patients circulating cell populations, serum, and wound site pre- and post- treatment and bank these samples for further studies to include (but not limited to):

[00268] Serum pre-apheresis and on each day of treatment, but prior to the treatment, and 1 month after final treatment. These samples will be available for ELISA evaluation of individual circulating chemokines/cytokines of interest or, hopefully, full proteomics analysis and comparison at different time points for each patient and between patients.

[00269] Punch biopsy of periphery and center of wound on each day of treatment, but prior to the treatment, 1 month after final treatment. Each biopsy will be divided in half, one piece for frozen tissue one for formalin fixing and paraffin embedding. These tissues will available for

immunohistochemical staining for cell populations and locally diffused cytokines and chemokines and their receptors on cell membranes, proliferation and apoptosis markers as per standard protocols.

[00270] Quantification of different subgroups of circulating stem cells in peripheral blood prior to mobilization with G-CSF and at time of apheresis (i.e. post-GSF), including, but not limited to: CD34+, c-kit⁺, thy- l^!o, Sca-1⁺, lin^" ("KTLS cells"), very small embryonic like stem cells (VSELS), and MSCs.

EXAMPLE 2

[00271] The MSCs obtained using the methods as described herein can be used for treating or repairing damage to the bones and for other orthopedic indications. Of particular interest is the use of the PB-derived MSCs and BM-derived MSCs for the treatment to reduce the incidence of stress fracture during intense physical training, or repair damage to bones which to not heal using conventional therapeutic methods (e.g. bone stimulation, hormones and immobilization). There are approximately 8 million fractures in the US population annually and close to 10% have impaired healing. In the military in general, stress fracture rate in men during basic training is up to 5%; in women, the rate is up to 21%. In the army, the numbers are 2.6% for men and 8.1% for women. Specific skeletal sites at risk for fracture are the ulna (rifle training); femoral neck (stress fracture); upper and lower limbs and blast injuries of the mandible, craniofacial bones and clavicle. These fractures result in $10 million annually in medical costs and lost duty time across all branches of the military. Accordingly, autologous MSCs obtained from subjects using the methods as disclosed herein could facilitate the healing of non-union bone fractures.

[00272] Fracture Non-Union Treatment using Percutaneou ly Placed, Culture Expanded, Autologous Mesenchymal Stem Cells

[00273] Long bone fracture non-union is a serious health issue that greatly adds to the costs of average bone fracture treatment. Treatment can take several forms, often requiring surgery including bone grafting and/or revisions of the initial open reduction, internal fixation (ORIF) procedure. More conservative options include the use of bone morphogenic proteins and bone stimulators in conjunction with surgical approaches. These procedures have a relatively high failure rate, indicating there is a clear need for newer, more effective approaches to facilitate treatment of non-union fractures.

[00274] In this study, the inventors demonstrate that PB-derived MSCs and BM-derived MSCs obtained by the methods as disclosed herein can be safely used and are effective in repairing damage to bone, and demonstrate preliminary efficacy of P B-derived MSCs and BM-derived MSCs administered via radiographicallv guided injection to promote bone regeneration in Fracture Non-union. These PB-derived MSCs and BM-derived MSCs enhance the tissue environment for healing as well as , restoration function by increasing regeneration of bone.

[00275] Without wishing to be bound by theory, bone is a specialized tissue that undergoes

continuous remodeling involving a balance between new formation and resorption. When bone is broken, mesenchymal stem cells (MSCs) are recruited to the site of injury. MSCs are multipotent cells found in human adult tissues including bone marrow (BM), synovial tissues, adipose tissues and peripheral blood (PB). Since they are derived from the mesoderm, MSCs have the capacity to differentiate into bone, cartilage, muscle, and adipose tissue. Normal fracture healing cannot take place without the presence of endogenously available MSCs, as these cells differentiate into a variety of cells needed for bone repair. While drugs have not been particularly effective in facilitating bone fracture healing, a number of studies have suggested that direct application of MSCs to sites of non-union fractures may be effective in healing the damaged bone. MSC lineages have been successful in a number of animal models and in humans to regenerate cartilage and bone. Accordingly, autologous PB-derived MSCs and BM-derived MSCs obtained by the methods as disclosed herein can be administered to sites of bone fracture in a manner that allows the cells to differentiate into osteoblasts and other mature cells needed for healing. Accordingly, the PB- derived MSCs and BM-derived MSCs as disclosed herein are useful as a bone regeneration product in treating non-union bone fractures. [00276] Therefore, PB-derived MSCs and BM-derived MSCs obtained from mobilized blood according to the methods as disclosed herein can be used to treat various conditions including Fracture Nonunion.

[00277] The inventors have demonstrated a method to isolate viable MSCs from mobilized peripheral blood, and these can be utilized in methods for autologous MSCs cell therapy for chronic wounds and orthopedic indications. Since the MSCs are autologous, there is limited or no risk of rejection. The inventors have demonstrated that administration of G-CSF (2 -days at 480ug, subcutaneous) demonstrated that MSCs could be mobilized from human BM to PB. Alternatively, the inventors have also demonstrated that MSCS can be mobilized into peripheral blood by a single dose of AMD3100 (240ug/kg, subcutaneous). The inventors demonstrate that PB-derived MSCs and BM- derived MSCs can be collected by the methods as disclosed herein and optionally subsequently expanded and/or cryopreserved.

[00278] Efficacy of the autologous BM-MSC and PB-MSC to treat Fracture Nonunion

[00279] To assess the efficacy of MSCs to treat non-union fractures, the inventors conduct a 12 month randomized, placebo controlled, double blind multi-center phase 1 clinical trial employing 100 patients total, divided into 4 groups of 25 patients. One group was treated with BM-MSCs, a second group was treated with PB-MSCs and two control groups will be treated with either autologous platelet lysate (PL, used to expand MSCs) or phosphate buffered saline (PBS). Patients were be enrolled and treated at 4 orthopedic specialty hospitals. Cells will be processed and expanded at one central cell culture facility. The primary endpoint to determine healing of Fracture non-union was measured by thin slice CT of the fracture site. Efficacy of the MSCs will be assessed if the fracture non-union is significantly less (P<0.05) than control treatments.

[00280] Methods:

[00281] Transplant Procedure includes: 1. Whole Bone Marrow Aspirate: Coincident with the marrow harvest procedure, 200cc of heparmized IV venous blood was drawn to be used for creating autologous PL. Marrow aspirate was drawn into a two 30 ml syringes containing 30,000 IU Heparin. The nucleated cells are separated and washed once in PBS, counted, and then re- suspended in DMEM + 10% PL and placed in a 4°C transport package along with the 200 ml of whole intravenous blood already collected and transported within 24 hrs to the cell culture site.

[00282] 2. Drug-induced mobilization and collection of MSCs: Patients were mobilized by using AMD3100 (240 ug/kg, s.c.) 4 hours prior to collection. Apheresis was performed to collect ~300cc mobilized peripheral blood. Approximately 200cc of heparinized IV venous blood was drawn to be used for creating autologous platelet lysate (PL). The apheresis product was placed in a 4°C transport package along with the 200 ml of whole intravenous blood already collected and transported via 24 hour delivery to the cell culture site.

[00283] 3. Autologous MSC expansion: Cells were be seeded at IxlO⁶ cells/cm₂ in a monolayer flask and incubated at 37°C/5% C02 in a humidified environment. The medium (containing autologous PL) was changed after 3 days, removing non-adherent cells. MSC colonies will develop 6-12 days after seeding. Each culture is passaged 1 :3 after reaching 40-50% confluence. MSCs are grown to the lst-3rd passage, and then suspended in phosphate buffered saline (PBS) and the concentration of autologous PL that corresponds with their maximal in-vitro culture expansion rate.

[00284] 4. Treatment product handling. Transplant procedure: Final MSC dose is the largest available with an expected yield of up to 1.0 x 10⁷ cells. The MSCs are placed into a sterile syringe and then into a sterile delivery bag and into a 4°C cooler for transport to the operating room. Required instructions to the staff will be included along with the product. The patient will be returned to a sterile operating room and the area of the non-union site will be prepped using betadine and sterile gloves. A sterile trocar is then be inserted on c-arni into the fracture site at several locations. Visipaque diluted 1 : 2 with PBS will be used to establish flow of radiographic contract in the fracture site. The syringe sample was injected into areas where dye flow can be established. The trocar was removed. The patient are instructed to remain still for 30 minutes to allow for cell attachment.

[00285] Outcome Endpoint Measurement: The efficacy of MSC to improve healing of the fracture size is determined using thin slice CT scans of the fracture site at Pre-op, 1, 3, 6, and 12 months. The scout films are used to define the fracture site area. To limit radiation exposure, the field of view is defined as 2 cm proximal and 2 cm distal to the fracture site.

EXAMPLE 3

[00286] The inventors have previously demonstrated that human cord blood contains a population of small (smaller in size than erythrocytes) CXCR4⁺CD133⁺CD34"SSEA-4⁺Oct-4!in^~CD45^~ cells (Leukemia 2007:21 ;297-303) and that these cells are mobilized into peripheral blood during tissue organ damage as seen for example in heart infarct (J. Am. Coll. Cardiol., 2009:53;l-9.) or stroke (Stroke. 2009:40; 1237.). Similar cells were also reported in murine organs, and more importantly we described that these cells may differentiate in vitro into cells from all three germ layers (Leukemia 2006:20;857-869). To explore the possibility that human VSELs could become a source of pluripotent stem cells in regenerative medicine, the inventors developed an efficient strategy to isolate these cells from adult patients. [00287] The inventors demonstrated that VSELs, similar to their murine counterparts, could be mobilized into peripheral blood after granulocyte colony stimulating factor (G-CSF) injection {Stem Cells 2008:26;2083-2092). The inventors demonstrated this by enrolling a group of young healthy donors who were mobilized for two consecutive days using G-CSF (480 μg/day

subcutaneously). On the third day nucleated cells (TNC) were collected by apheresis.

[00288] The inventors evaluated number of VSELs in peripheral blood (PB) samples before and after G-CSF mobilization as well as the final number in the apheresis product. At least 1 million of TNC were acquired and analyzed by FACS Diva software. Three different fractions of non- hematopoietic stem cells enriched for VSELs (Lin7CD457CD133⁺, Lin7CD457CD34⁺, Lin7CD45^~ /CXCR4^T) as well as their CD45 positive hematopoietic counterparts were analyzed. The absolute numbers of cells from each population, contained in 1 \ih of sample, were computed based on percent content of each population and TNC count for each individual sample.

[00289] The inventors determined that after G-CSF mobilization, human peripheral blood contains a population of lm^" CD45^" mononuclear cells that express CXCR4, CD34 and CD133 antigens.

These lin^" CD45^" CXCR4^" CD 133^* CD34⁺ cells are highly enriched for mRNA for intra-nuclear pluripotent embryonic transcription factors such as Oct-4, Sox2 and Nanog. More importantly the inventors found that Oct-4 was expressed in nuclei of mobilized VSELs and that these cells also express the cell surface marker SSEA-4, the early embryonic glycolipid antigen commonly used as a marker for undifferentiated pluripotent human embryonic stem cells. The inventors observed that these adult peripheral blood-derived VSELs are slightly larger than their counterparts identified in adult murine bone marrow, but are still very small. In addition, these human peripheral-blood derived VSELS possess large nuclei containing embryonic-type unorganized euchromatin.

[00290] The inventors clearly demonstrate that before G-CSF mobilization, only very few VSELs were detectable in peripheral blood, whereas following G-CSF induced mobilization there was a very significant increase with in excess of 10⁶ VSELs present in the apheresis product representing less than 0.01% of TNC. The inventors demonstrate that w^rhile VSELs are relatively rare cells, they are mobilized into peripheral blood and that G-CSF induced mobilization is useful to obtain human pluripotent stem cells for regenerative medicine.

REFERENCES

[00291] All references, patents and patent applications cited herein and throughout the specification are herewith incorporated by reference in their entirety.

Claims

1. A method for obtaining peripheral blood-derived human mesenchymal stem cells from a subject, comprising;

2. A method for increasing the population of human mesenchymal stem cells in the peripheral blood of a subject comprising;

a. administering to the peripheral blood of a subject an effective amount of G-CSF or GM-CSF for a duration of 4 days or less;

b. obtaining a population of human mesenchymal stem cells from a peripheral blood sample obtained from the subject, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD 105+ CD29+ and CD73+ cell surface markers; and

3. A method for obtaining human mesenchymal stem cells from a subject, comprising;

a. contacting a peripheral blood sample obtained from the subject with an effective amount of G-CSF or GM-CSF to increase the number of human mesenchymal stem cells in the peripheral blood sample;

b. obtaining a population of human mesenchymal stem cells from the peripheral blood sample, wherein the human mesenchymal stem cells are negative for CD34-, CD45- cell surface markers, and positive for CD44+, CD90+, CD105+, CD29+ and CD73+ cell surface markers; and c. separating human mesenchymal stem cells relative to other somatic stem cells in the peripheral blood.

4. The method of any of claims 1 or 2, wherein the effective amount of G-CSF or GM-CSF is administered to the subject for a duration of 3 days or less.

5. The method of any of claims 1 or 2, wherein the effective amount of G-CSF or GM-CSF is administered to the subject for a duration of 2 days or less.

6. The method of any of claims 1 or 2, wherein the effective amount of G-CSF or GM-CSF is administered to the subject for a duration of 1 day.

7. The method of any of claims 1 to 6, wherein the subject is a healthy subject.

8. The method of any of claims 1 to 7, wherein the population of human mesenchymal stem cells is obtained from the peripheral blood sample using a size-based separation process.

9. The method of any of claims 1 to 8, wherein the population of human mesenchymal stem cells are obtained from the peripheral blood sample using negative selection to exclude non- mesenchymal stem cells, whereby the population of human mesenchymal stem cells are separated and collected from a sample comprising a population of mesenchymal stem cells and a population of non-mesenchymal stem cells.

10. The method of any of claims 1 to 9, wherein the population of human mesenchymal stem cells are obtained from the peripheral blood using a combination of any of following processes; positive selection based on cell surface markers, negative selection based on cell surface markers, positive selection based size, negative selection based size.

11. A method for obtaining human mesenchymal stem cells from a subject, comprising;

12. The method of claims 3 or 1 1, wherein the peripheral blood sample is a cultured peripheral blood sample.

13. The method of claim 1, 2, 3 or 1 1 wherein the peripheral blood sample is obtained from the subject through apheresis.

14. The method of claim 13, wherein the hematocrit range of the apheresis product is 2-3%.

15. The method of claims 3 or 11 , wherein the peripheral blood sample is a fresh peripheral blood sample.

16. The method of any of the above claims, wherein the population of human mesenchymal stem cells obtained from the peripheral blood sample is expanded in culture.

17. The method of any of the above claims, wherein the population of human mesenchymal stem cells obtained from the peripheral blood sample is cryopreserved.

18. The method of any of the above claims, wherein the subject is a human subject.

19. A clonal cell line comprising a substantially pure population of human mesenchymal stem cells isolated using a method of any of the above claims.

20. A container comprising a suitable media and a clonal cell line of a population of human mesenchymal stem cell of claim 18.

21. The container of claim 19, wherein the suitable media and clonal cell line of a population of human mesenchymal stem cell are cryopreserved.

22. A cryopreserved population of human mesenchymal stem cell obtained by any of the methods of claims 1 to 17.

23. Use of a population of human mesenchymal stem cells, or differentiated progeny thereof, for the treatment of a disease or disorder of a subject in need thereof, wherein the population of human mesenchymal stem cells is isolated using a method of any of the above claims, and wherein the population of human mesenchymal stem cells, or differentiated progeny thereof is administered to a subject in need thereof for autologous regeneration therapy.

24. A method for treating a disease or disorder in a subject with autologous mesenchymal stem cells (MSCs) comprising:

25. The method of claim 23, wherein the enrichment of MSCs is by a positive selection method.

26. The method of claim 23, wherein the enrichment of MSCs is by elutriation.

27. The method of claim 23, wherein the MSC population as been cryopreserved.

28. The method of claim 23, wherein the enriched population of MSCs comprises non-MSC cells.

29. The method of claim 23, wherein the enriched population of MSCs comprises at least 10% of MSCs.

30. The method of claim 23, wherein the enriched MSC population is a substantially pure population of MSCs.

31. The method of claims 23 or 26, wherein the MSC population has been expanded in vitro prior to administering to the subject.

32. The method of claim 23, wherein the subject is a human subject.

33. A method for obtaining peripheral blood-derived human stem cells from a subject,

comprising;

a. administering to the subject an effective amount of a mobilization agent for a duration of 4 days or less;

b. obtaining a population of human stem cells from a peripheral blood sample obtained from the subject; and

34. The method of claim 33, wherein the stem cells are mesenchymal stem cell.

35. The method of claim 33, wherein the stem cells are "very small embryonic-like stem cells (VSEL).

36. The method of claim 33, witerein the mobilization agent is G-CSF or GM-CSF.

37. The of claim 33, wherein the mobilization agent is selected from the group consisting of interleukin-17, AMD3100 , cyclophosphamide (Cy), Docetaxel and (DXT).