WO2004003183A1 - Immunoliposome conjugated with anti-upa antibody - Google Patents

Immunoliposome conjugated with anti-upa antibody Download PDF

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Publication number
WO2004003183A1
WO2004003183A1 PCT/KR2003/001233 KR0301233W WO2004003183A1 WO 2004003183 A1 WO2004003183 A1 WO 2004003183A1 KR 0301233 W KR0301233 W KR 0301233W WO 2004003183 A1 WO2004003183 A1 WO 2004003183A1
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upa
cells
immunoliposome
cancer
cell
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PCT/KR2003/001233
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French (fr)
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Yoon-Hoh Kook
So-Yon Woo
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Yoon-Hoh Kook
So-Yon Woo
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Priority to AU2003243037A priority Critical patent/AU2003243037A1/en
Publication of WO2004003183A1 publication Critical patent/WO2004003183A1/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/40—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against enzymes
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00—Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/10—Cells modified by introduction of foreign genetic material
    • C12N5/12—Fused cells, e.g. hybridomas
    • C12N5/16—Animal cells
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00—Medicinal preparations containing antigens or antibodies
    • A61K39/395—Antibodies; Immunoglobulins; Immune serum, e.g. antilymphocytic serum
    • A61K39/39533—Antibodies; Immunoglobulins; Immune serum, e.g. antilymphocytic serum against materials from animals
    • A61K39/3955—Antibodies; Immunoglobulins; Immune serum, e.g. antilymphocytic serum against materials from animals against proteinaceous materials, e.g. enzymes, hormones, lymphokines
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00—Medicinal preparations containing antigens or antibodies
    • A61K2039/505—Medicinal preparations containing antigens or antibodies comprising antibodies
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/70—Immunoglobulins specific features characterized by effect upon binding to a cell or to an antigen
    • C07K2317/77—Internalization into the cell

Definitions

  • the present invention relates to an immunoliposome conjugated with a specific monoclonal anti-uPA antibody, which is a selective drug delivery system targeted to such cells overexpressing uPA (urokinase type plasminogen activator) as cancer cells or endothelial cells participating in angiogenesis in cancer tissue.
  • uPA urokinase type plasminogen activator
  • Anticancer chemotherapy is one of the essential methods, such as surgery, radiation therapy and immunotherapy, to treat a cancer.
  • most of normal cells, especially rapidly dividing cells, are also susceptible to chemotherapeutic agents.
  • chemotherapeutic agents Because the side effects resulting from the cytotoxicity to normal cells are unavoidable, many strategies to kill specifically the cancer cells have been developed.
  • the concept of drug targeting and controlled drug delivery is used in an attempt to improve the therapeutic index of drugs by increasing their localization to specific organs, tissues or cells and by decreasing their activity and potential toxic side effects at normal sensitive sites. Liposome is one of them.
  • Liposomes are colloidal particles of lipid bilayer membranes and are composed of self-assembled amphiphiles (mostly phospholipids) in contact with water.
  • Different kinds of drugs can be encapsulated in liposomes.
  • Specific antibody molecules can be conjugated with liposome to make an immunoliposome, which can improve the specificity to target cells by specific antigen-antibody interaction.
  • liposome When the specific antibody conjugated with liposome recognizes antigen on cell surface, the liposome is internalized into cytosol by endocytosis, along with drugs therein. Therefore, drugs can be concentrated selectively to specific target cells and organ using liposome (Huwyler J., Wu D., Pardridge W. M., Brain drug delivery of small molecules using immunoliposomes. Proc. Natl. Acad. Sci. USA 93:14164-14169, 1996; Spragg D., Alford D. R., Greferath R., Larsen C. E., Lee K. D., Gurtner G. C, Cybulsky M. I., Tosi P. F., Nicolau C, and Gimbrone Jr. M.
  • proteases produced and secreted by normal cells for normal physiological functions, are related to those characteristics of cancer cells.
  • One of the most important proteases expressed by cancer cells is urokinase type plasminogen activator (uPA) (Andreasen P. A., Egelund R., Petersen H.H., The plasminogen activation system in tumor growth, invasion, and metastasis. Cell Mol. Life Sci.51:25- 40, 2000).
  • uPA is a serine protease which activates plasminogen to plasmin and has broad substrate-specificity. Increased expression of uPA from cancer cells leads to marked degradation of extra cellular matrix (ECM).
  • Fig.l is a scheme showing protease involved in pericellular proteolysis for cancer invasion and metastasis.
  • uPA The expression of uPA is elevated in various cancer tissues such as lung, colon, breast, melanoma removed from patients, The invasiveness of cell line is dependent on the expression of uPA (de Bruin A.F., Grissioen.G.Nerspaget H.W.,
  • Plasmin generated by uPA activates several MMPs (matrix metalloproteinases), and therefore, accelerates the degradation of laminin and type IV collagen, the components of extracellular matrix (Mackay A. R., Corbitt R. H., Hartzler J. L., Thorgeirsson U. P., Basement membrane type IV collagen degradation: Evidence for the involvement of a proteolytic cascade independent of metalloproteinases. Cancer Res. 50:5997-6001, 1990).
  • uPA is regarded as a key molecule, which, in turn, means an important target molecule to control the invasion and metastasis of cancer cells.
  • uPA is secreted as inactive single chain form (scuPA) and activated to two chain uPA (tcuPA) (Petersen L. C, Lund L. R., Nielsen L. S., Dano K., Skriver L., One chain urokinase-type plasminogen activator from sarcoma cells is a proenzyme with little or no intrinsic activity. J. Biol. Chem. 263:11189-11195, 1988).
  • uPA In activation of uPA, the receptor of uPA, uPAR is important (Ellis V., Scully M. F., Kakkar, V. V., Plasminogen activation initiated by single-chain urokinase-type plasminogen activator. potentiation by U937 monocyte. J. Biol. Chem. 264:2158-2188 1989).
  • the interaction of uPA and uPAR does not influence on enzymatic activity of uPA and induces co- localization of plasminogen on cell surface, and therefore, accelerated generation of plasmin in pericellular area is expected.
  • uPA-uPAR The interaction of uPA-uPAR is a key step in the point of co-localization of molecules related in the generation of plasmin, which finally enables cancer cells to degrade extracellular matrix and achieve invasion and metastasis
  • Adv. Cancer Res. 44: 139-266, 1985 Hollas W., Blasi F., Boyd D., Role of the urokinase receptor in facilitating extracellular matrix invasion by cultured colon cancer. Cancer Res. 51 :3690
  • antisense RNA of uPA (Yu H., Schultz R. M., Relationship between secreted urokinase plasminogen activator activity and metastatic potential in murine B16 cells transfected with human urokinase sense and antisense genes. Cancer Res. 50:7623-7633, 1990), and antisense RNA of uPAR (Kook Y. H., John A., Zelent A., and Ossowski L., The effect of antisense inhibition of urokinase receptor in human squamous cell carcinoma. EMBOJ. 13:3983-3991, 1994).
  • uPAR bound uPA activity is inhibited by the binding of plasminogen activator inhibitors (PAI). Then, with the binding of ⁇ 2-macroglobuoin ( ⁇ 2-MR) the complex, uPAR-uPA-PAI, is internalized to cytosol, and the uPA-PAI are degraded. Only the uPAR is recycled on cell surface (Nykjasr A., Conese M.,
  • Fig.2 is a scheme showing the internalization of uPAR-uPA-PAI complex into the cytosol and their interaction with ⁇ 2-MR.
  • single chain uPA secreted as inactive form (A)
  • uPAR binds to uPAR and is activated to two chain uPA (B), which forms a complex with PAI and ⁇ 2-MR (D).
  • the uPAR-uPA-PAI- ⁇ 2-MR complex is, then, internalized.
  • the uPA and PAI are degraded and only the uPAR and ⁇ 2-MR molecules are recycled to cell membrane (C).
  • Anti-uPA antibody can initiate internalization (E). This internalization process can be also induced by anti-uPA antibody instead of PAI (Andreasen P. A., Sottrup- Jensen L., Kj ⁇ ller L., Nykjaer A.,
  • Blasi F. Accessibility of receptor- bound urokinase to type- 1 plasminogen activator inhibitor. Proc. Natl. Acad. Sci. USA 86: 4828 ⁇ 1832, 1989; Ellis V., Wun T.C., Behrendt N., R ⁇ nne E. Dan ⁇ K., Inhibition of receptor-bound urokinase by plasminogen activator inhibitors. J. Biol. Chem. 265: 9904-9908, 1990; Nykjasr A., Conese M., Christensen E.
  • uPAR-uPA-PAI is a novel target of drug delivery based on the overexpression of uPA in cancer cells and its key role in invasion and metastasis. Furthermore, uPA is also overexpressed in endothelial cells participating in angiogenesis, which is critical for tumor growth. Endothelial cells also utilize proteases including uPA to degrade ECM when they migrate to form new blood vessels.
  • the growth of tumor may be inhibited by directly killing the cancer cells and by inhibiting the angiogenesis through killing the endothelial cells, which are recruited to make new blood vessels in tumor tissue. Therefore, if a cytotoxic agent is specifically delivered to uPA-overexpressing cells, such as cancer cells and endothelial cells, it will achieve two major goals in the treatment of cancer.
  • a fused cell of myeloma cells and spleen cells of mouse immunized with uPA (urokinase type plasminogen activator), which secretes anti-uPA monoclonal antibody Preferably, the fused cell is the hybridoma clone, 1E11.
  • an anti-uPA monoclonal antibody which is secreted from the fused cell.
  • an immunoliposome conjugated with the anti-uPA monoclonal antibody Preferably, the immunoliposome includes any drugs or chemical agents such as anticancer drugs, or DNA and contrast media such as fluorescent materials and isotopes, therein.
  • a novel anti-human uPA monoclonal antibody is produced and conjugated with liposome to make a novel immunoliposome.
  • the anti- uPA immunoliposome of the present invention in which anticancer drugs are encapsulated, may be used for the specific drug delivery to cancer cells.
  • the present invention will be described in detail.
  • chemotherapeutic agents of high therapeutic index are continuously developed and used for the treatment of cancer, most of them are toxic not only to tumor cells but also normal cells. Unlike the surgery or radiation therapy the side effect of chemotherapy is not local but systemic.
  • controlled delivery of the anticancer agents to tumor tissue has been strongly required to increase therapeutic efficacy.
  • the liposomal formulation of anticancer drug was tried
  • Liposome is a micelle composed of phospholipids and amphiphiles. It is similar and can be fused with cellular membrane. When a drug is encapsulated in liposome it can be delivered to cell by the fusion of liposome and cell membrane. Compared to other drug delivery methods, liposome offers several advantages including biocompatibility, low immunogenicity, low toxicity, and a wide range of physical properties that can be modified to control their biological activities (Gerd Bendas, Immunoliposomes: A Promising Approach to Targeting Cancer Therapy. BioDrugs 15(4): 215-224, 2001). Optimal size of liposome depends on the target. In tumor tissues, the vasculature is discontinuous, and fenestration, which is a discontinuous distribution of endothelial cells, varies from 100 to 780 nm in diameter.
  • normal vascular endothelium is 2 nm in most tissues, 6 nm in postcapillary venules, 40-60 nm in kidney glomerulus, and up to 150 nm in sinusoidal epithelium of liver and spleen (Seymour, L. W., Passive tumor targeting of soluble macromolecules and drug conjugates. CRC Crit. Rev. Ther. Drug Carrier Syst., 9: 135- 187, 1992). Therefore, immunoliposomes with the average size of 65-125 nm are small enough to be delivered from blood to target site in tumor tissue across the fenestration.
  • liposome-mediated drug delivery removal of liposomes from the circulation by fixed macrophages in reticuloendothelial system (RES), particularly in the liver and spleen.
  • RES reticuloendothelial system
  • Conventional liposome binds non-specifically to and is fused with cellular membrane, which means a non-specific drug delivery.
  • the specificity of liposome can be increased by coating ligands that can recognize cell surface molecules (Martin, F. J., Hubbell W. L., Papahadjopoulos D., Immunospecific targeting of liposomes to cells: a novel and efficient method for covalent attachment of Fab' fragments via disulfide bonds. Biochemistry. 20: 4229-4238, 1981; Martin F.
  • Immunoliposomes made of specific antibodies or portions of antibodies to tumor cells would be an effective mean of tumor targeting. For this approach, many factors must be taken into consideration, including proper choice of target antigen on the cell surface, antibody specificity, and antibody-liposome linkage (Park, J. W., Hong, K., Kirpotin, D. B., Papahadjopoulos, D., and Benz, C. C, Immunoliposomes for cancer treatment. Adv. Pharmacol., 40: 399 ⁇ 135, 1997).
  • Targeting on tumor cell surface molecules which shows markedly different pattern of expression profile from normal cells, and making immunoliposome with highly specific antibody against those molecules would be a powerful tool for selective delivery of anticancer drugs.
  • the present invention achieves this goal by making specific monoclonal antibody against uPA, which is highly expressed in and is a prominent characteristic of malignant tumor cells showing invasion and metastasis.
  • the strategy of immunoliposome targeting on uPA molecule seems to be quite efficient in that the cancer cells can be killed by both direct and indirect pathway.
  • uPA is an enzyme that plays a central role in invasion and metastasis of cancer cells, and therefore, it is a good target for the regulation of invasion and metastasis.
  • uPA is an enzyme that plays a central role in invasion and metastasis of cancer cells, and therefore, it is a good target for the regulation of invasion and metastasis.
  • the cancer cells there is another important component, which also should be a target for efficient cancer treatment, in tumor tissues. It is the vascular endothelial cell, which is involved in new blood vessel formation for tumor tissues.
  • tumor tissues larger than 1 mm in diameter are unable to be supplied with oxygen and nutrients to the center of the mass.
  • angiogenesis (Bouck N., Stellmach V., Hsu S.C., How tumors become angiogenic. Adv. Cancer Res. 69: 135-74, 1996; Folkman J., Angiogenesis in cancer, vascular, rheumatoid and other disease. Nature Med. 1: 27-31, 1995; Risau W., Mechanisms of angiogenesis. Nature 386:671-674, 1997).
  • vascular .endothelial cell proliferates and moves toward the cancer cells, which need blood vessels.
  • endothelial cells should degrade extracellular matrix using various proteases.
  • uPA is one of key molecules in this mechanism (Mignatti P., Rifkin D.B., Plasminogen activators and matrix metalloproteinases in angiogenesis. Enzyme Protein. 49: 117-137, 1996).
  • the expression level of uPA and uPAR is raised by stimulation of angiogenic factors in endothelial cells. It alters extracellular proteolytic activity of endothelial cell (Pepper M. S., Mandriota S.
  • VEGF Vascular Endothelial Growth Factor
  • anticancer drugs encapsulated in the anti-uPA immunoliposome can indirectly kill tumor cells.
  • the immunoliposome targeting uPA molecule suggests a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway.
  • the key point of anti-uPA immunoliposome is the specificity of anti-uPA atibody, which recognizes bound uPA on the cell surface receptor.
  • contrast media fluorescent materials and isotopes
  • DNA may be included in the immunoliposome of the present invention.
  • DNA is included in the immunoliposome to be delivered to a target cell or tissue for protein expression (or gene therapy). In such gene targeting, lipid of positive charge is used.
  • the immunoliposomes including contrast media (isotopes or fluorescent materials) therein may be used as a probe for a specific site or as a photosensitizer, in which the chemical agents are localized in a specific site and then activated by laser or radiation for the treatment.
  • Fig. 1 is a scheme showing protease involved in pericellular proteolysis for cancer invasion and metastasis.
  • Fig.2 is a schemee showing the internalization of uPA-uPAR-PAI complex into the cytosol and their interaction with 2-MR.
  • Fig. 3 is a graph showing the recognition of uPA on uPAR by anti-uPA monoclonal antibody produced by the hybridoma clone, 1E11.
  • Fig. 4 is a photograph showing co-localization of anti-uPA immunoliposomes and uPAR in HEp3 cells.
  • Fig 5 is a photograph showing internalization of anti-uPA immunoliposomes.
  • Fig. 6 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to epidermoid cancer cell lines.
  • Fig. 7 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to breast cancer cell lines.
  • Fig. 8 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to leukemia cell lines.
  • Fig 9 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to ECGS stimulated HUVEC.
  • Fig. 10 is a photograph showing cell death by treatment of various type of drugs (free drug, liposomal drug, immunoliposomal drug) traced with realtime imaging technique.
  • an anti-uPA monoclonal antibody of the present invention fused cells producing the monoclonal antibody, the immunoliposome conjugated with the monoclonal antibody, and the manufacturing process thereof.
  • Human cancer cell lines were obtained from the Korean Cell Line Bank (KCLB, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea).
  • breast cancer cell lines, MCF-7, MDA-MB-231 and SCC-1395 were maintained as monolayer cultures in Roswell Park Memorial Institute (RPMI)- 1640 (GIBCO BRL, Gaithersburg, MD) and Leukemia cell lines, HL60, K562, Jurkat, THP-1 and U937, were maintained as suspended cultures in Roswell Park Memorial Institute (RPMI-1640, GIBCO BRL, Gaithersburg, MD) supplemented with 10% fetal bovine serum (FBS; GIBCO BRL), 100 units/ml penicillin, and 100 ⁇ g/ml streptomycin in a humidified incubator at 37"C and 5% CO 2 .
  • FBS fetal bovine serum
  • streptomycin 100 fetal bovine serum
  • Spleen cells of immunized Balb/c mice were prepared as previously described (K ⁇ hler G., Milstein C, Continuous culture of fused cells secreting antibody predefined specificity. Nature 256:495-498, 1975; Littlefield JW., Selection of hybrids from matings of fibroblasts in vitro and their presumed recombinants. Science 145:709-710, 1964). They were fused with myeloma cells (P3-X63-Ag8.653) by using 50%(w/v) polyethylene glycol (PEG 15000, BM).
  • Hybridoma clones secreting anti-uPA antibody were screened using indirect ELISA and direct cell ELISA, in which the human uPA and HEp3 cells were coated on the surface of the plate, respectively.
  • a peroxidase-conjugated rabbit anti-mouse immunoglobulin (PROMEGA, USA) and O-phenylenediamine (OPD) were used for enzymatic detection.
  • the optical density (at 492 nm) was measured in an ELISA reader (Titertek Multiscan Flow Laboratories Pty Ltd., Australia). Isotype of antibody was determined using ImmunoPure Monoclonal Antibody Isotyping Kit I (PIERCE, USA) according to manufacturer's instruction.
  • Hybridoma cells (5 xlO 6 cells/0.5 ml) were injected into the peritoneal cavity of 6-week old Balb/c mice. One or two weeks after the injection, mice were sacrificed and ascitic fluids were harvested to purify anti-uPA monoclonal antibody (IgG) by protein G-Sepharose column (Amersham, USA).
  • the clone 1E11 which showed strong positive reactivity in indirect ELISA, reactive to surface bound uPA of adherent Hep3 cell, was selected.
  • the culture supernatant of 1E11 was not reactive to tissue type plasminogen activator (tPA) by western blot (data not shown).
  • the isotype of 1E11 antibody was IgGl and K chain.
  • the hybridoma clone 1E11 as a fused cell secreting a specific antibody to uPA, was deposited with the KCLRF (Korean Cell Line Research Foundation) as accession number KCLRF-BP-00056 on June 5, 2002.
  • the amount of uPA and uPAR on cell surface was analyzed by flowcytometry.
  • the cells were detached with trypsin-EDTA, washed with PBS and suspended to be the concentration of 2xl0 6 cells/ml in PBS with 1% FBS and 0.1% sodium azide.
  • Antibodies to uPA and uPAR, and anti-human uPAR IgG were diluted (x 200) and added to the cells. Then the cells were incubated at 4°C for 1 hour. After the incubation, cells were washed with PBS and incubated with fluorescein-isothiocyanate (FITC)-conjugated anti-mouse IgG (Cappel, USA) ( ⁇ 400) at 4°C for 1 hour. The analysis was performed with FACScan flowcytometer (Becton Dickinson, San Jose, CA).
  • FITC fluorescein-isothiocyanate
  • Fig. 3 is a graph showing the recognition of uPA on uPAR by anti-uPA monoclonal antibody produced by the hybridoma clone, 1E11. Compared to the control
  • Liposomes were prepared essentially as previously described (Compagnon, B., Moradpour, D., Alford, D. R., Larsen, C. E., Stevenson, M. J., Mohr, L., Wands, J. R.
  • Lipids in chloroform were combined at the following ratios: Dioleoylphosphatidylcholine (DOPC, Avanti Polar Lipids) : Cholesterol (SIGMA) : Dioleoylphosphatidylethanolamine-N-[4-(maleimidophenyl)butyrate] ' (MPB-PE,
  • Lipids were hydrated and frozen and thawed four times, then extruded for 15 cycles through two stacked polycarbonate membranes (pore size 0.1 ⁇ m, Corning) using a hand-held extruder (Avanti Polar Lipids).
  • the diameter of liposome 80 to 180 nm was measured by quasi-elastic light scattering with an ⁇ 4 Plus Submicron Particle Sizer (Coulter).
  • Anti-uPA monoclonal antibody was purified from mice ascites and chemically modified as previously described (Weston P.D. Devries J.A. Wrigglesworth R., Conjugation of enzymes to immunoglobulins using dimeleimides. Biochem. Biophys. Ada 612:40-49, 1980).
  • SAT A succinimidyl- S-acetylthioacetate
  • HBSE buffer 50-100 volumes of HBSE buffer changed twice, deacetylated with a 10% (vo vol) addition of deacetylation solution, 50 mM sodium phosphate, 25 mM EDTA, and 0.5 M hydroxylamine (pH 7.5) for 2 hours, and then immediately added to liposomes.
  • the liposome-antibody mixture was gently shaken at 4°C overnight, and then immunoliposomes were separated from free antibody and deacetylation solution by chromatography (Sepharose CL-4B; 1x30 cm; HBSE buffer). Lipid mass was determined by phosphate assay (Chen, P. S., Jr., Toribara, T. Y., Warner, H., Microdetermination of phophorus. Anal. Chem. 28:1756-1758, 1956; Morrison W.R..
  • Daunorubicin-loaded liposome and immunoliposome Lipids were hydrated in 120 mM ammonium sulfate. After extrusion, liposomes were desalted in HBSE buffer by chromatography on Sepharose CL-4B (SIGMA), loaded with daunorubicin HC1 (50-200 mg/ml, 98% pure; SIGMA) as previously described (Haran, G., Cohen, R., Bar, L. K.&Barenholz, Y., Transmembrane ammonium sulfate gradients in liposomes produce efficient and stable entrapment of amphipathic weak bases. Biochim. Biophys. Ada 1151 :201-215, 1993;
  • 3,6,8-trisulfonic acid which is a membrane-impermeant pH-dependent fluorophore (green), was encapsulated in immunoliposome and treated for cancer cells. Color and location of florescence were traced with confocal microscopy (450 nm).
  • HEp3 cells grown on coverslip were washed with phosphate buffered saline and fixed for 10 min in 4% paraformaldehyde in PBS. Fixed cells were rinsed in PBS and then permeabilized with 0.1% Triton X-100 in PBS. Fetal Bovine Serum (10% in PBS) was used to block non-specific binding.
  • the coverslips were incubated with immunoliposome encapsulated with HPTS in PBS for 1 hour at 4°C and incubated at 37 °C for each time. For the staining of nuclei, cells were incubated with propidium iodide (10 mg/ml, SIGMA).
  • the coverslips were mounted onto glass slides using gelvatol and observed with a confocal laser scanning microscope (Bio-Rad MRC 1024, equipped with a Zeiss Axio-plan microscope). Depending on the cell thickness, 5 to 10 focal frames were taken along the Z-axis at 0.5 mm intervals and then merged to obtain a reconstructed image.
  • Hep3 cells were treated with anti- uPAR antibody (American Diagnostica. USA), incubated at 4°C for 1 hour, and washed three times with PBS. Then cells were treated with secondary antibody, which was conjugated with tetramethyl rhodamine isothiocyanate (TRITC, SIGMA).
  • TRITC tetramethyl rhodamine isothiocyanate
  • Fig. 4 is a photograph showing co-localization of anti-uPA immunoliposomes and uPAR in HEp3 cells.
  • HEp3 cells treated with HPTS-encapsulated anti-uPA immnoliposomes (green fluorescence) and anti-uPAR antibody (red fluorescence) were observed by confocal microscopy as described. Because of the co-localization of both fluorescences, which corresponds to uPA and uPAR, respectively, orange colors are appeared. It suggests the specific binding of immunoliposome to the uPA bound on the cell surface uPAR.
  • Cytotoxicity assay anticancer drug delivered by immunoliposome Immunoliposome encapsulated with anticancer drug, daunorubicin was made and used to kill cultured cancer cells.
  • the XTT assay kit (Boehringer Mannheim, Indianapolis, IN) was used for the cytotoxicity assay. Cells (1 x 10 4 /well) were plated into 96-well tissue culture plates. After 24 hours, cultured cells were treated with varying concentrations of daunorubicin in free, liposomal, and immunoliposomal form, and then incubated. Then, 50 ⁇ l of XTT solution was added to the culture and incubated for 4 hours. The absorbance was measured at 450 nm using a microplate reader (Dynatech, Chantilly, VA). The viability of leukemic cell lines was determined by [methyl- H]-thymidine incorporation assay.
  • Fig. 6 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to epidermoid cancer cell lines.
  • Tumor cells HEp3 and SM3 expressing different amount of uPAR (a), which means different amount of cell surface-bound uPA, were treated with varying amount of daunorubicin-loaded immunoliposomes for 24 hrs.
  • uPAR a
  • daunorubicin-loaded immunoliposome for 24 hrs.
  • anti- uPA immunoliposome showed marked cytotoxicity at the low concentrations of daunorubicin (c).
  • Three different formulations of daunorubicin (free daunorubicinj liposomal daunorubicin and immunoliposomal daunorubicin) were used.
  • Fig. 7 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to breast cancer cell lines.
  • the daunorubicin encapsulated in immunoliposome showed more effective cytotoxicity in those cells that have relatively more uPA on cell surface (HEp3 and MDA MB231) than others (b).
  • uPA and uPAR expressions are relatively low and high in MCF7 cells and MDA-MB-231 cells, respectively.
  • uPA expression was low but uPAR expression was higher than MDA-MB-231.
  • MDA-MB-231 cells were more efficiently killed than SCC-1395 at low concentration of daunorubicin, the cytotoxicity mediated by daunorubicin-loaded immunoliposome seemd to be more clearly dependent on the level of uPA than uPAR.
  • Fig. 8 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to leukemia cell lines.
  • Leukemia cell lines which show different amount of uPA and uPAR (a), were treated with varying amount of daunorubicin-loaded immunoliposomes. The marked cytotoxicity was observed in those cell lines that have more uPA and uPAR (HL60 and THP-1) than other cell lines (b).
  • HUVEC Human umbilical vein endothelial cell
  • ECGS endothelial cell growth supplement
  • Fig 9 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to ECGS-stimulated HUVEC.
  • HUVEC has comparable amount of uPA and uPAR as HEp3 cell (a). Similar patterns of cytotoxicity were observed in both cell lines (b). The treatment of daunorubicin-loaded immunoliposome on HUVEC showed similar cytotoxicity with HEp3.
  • Fig. 10 is a photograph showing cell death by treatment of various type of drugs (free drug, liposomal drug, immunoliposomal drug) traced with realtime imaging technique.
  • the immunoliposome targeting uPA molecule suggests a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway.
  • the key point of anti-uPA immunoliposome is the specificity of anti-uPA atibody, which recognizes bound uPA on the cell surface receptor.
  • specific binding to uPA on uPAR and internalization of their complex into cytosol was clearly shown by confocal microscopy. Encapsulated anticancer drug in immunoliposome showed effective cytotoxicity.
  • the immunoliposome Compared to the cytotoxicity of free daunorubicin and liposomal daunorubicin, which is independent on uPA, and therefore, acts non-specifically on both cancer cells and normal cells, the immunoliposome showed marked cytoxicity depending on the amount of cell surface uPA. The efficiency of the present immunoliposome was demonstrated i h various cell types having different amount of uPA on cell surface. It was noteworthy that leukemic cell lines which are cultivated in suspension, and therefore, have uPA and uPAR uniformly distributed on cell surface are more sensitive than monolayer cells in which uPA and uPAR is located on focal contact area.
  • the anti-uP A immunoliposome of the present invention is one of the possible candidates of efficient drug delivery system to uPA over-expressing cancer cells that may show malignant behavior, such as local invasion and metastasis.
  • Anticancer drugs encapsulated in the anti-uPA immunoliposome can not only directly kill tumor cells but also indirectly kill tumor cells by the interruption of oxygen and nutrients to tumor mass, which can be achived by killing the endothelial cells involved in angiogenesis. Therefore, the immunoliposome targeting uPA molecule may provide a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway.
  • the microorganism identified under I above was accompanied by

Abstract

The present invention relates to an immunoliposome conjugated with a specific monoclonal anti-uPA antibody, which is a selective drug delivery system targeted to such cells overexpressing uPA (urokinase type plasminogen activator) as cancer cells or endothelial cells participating in angiogenesis in cancer tissue. The immunoliposome conjugated with an anti-uPA monoclonal antibody which is secreted from a fused cell of myeloma cells and spleen cells of mouse immunized with human uPA is one of the possible candidates of efficient drug delivery system to uPA over-expressing cancer cells that may show malignant behavior, such as local invasion and metastasis. Anticancer drugs encapsulated in the anti-uPA immunoliposome can not only directly kill tumor cells but also indirectly kill tumor cells by the interruption of oxygen and nutrients to tumor mass, which can be achived by killing the endothelial cells involved in angiogenesis.

Description

IMMUNOLIPOSOME CONJUGATED WITH ANTI-UPA ANTIBODY
Technical Field
The present invention relates to an immunoliposome conjugated with a specific monoclonal anti-uPA antibody, which is a selective drug delivery system targeted to such cells overexpressing uPA (urokinase type plasminogen activator) as cancer cells or endothelial cells participating in angiogenesis in cancer tissue.
Background Art
Anticancer chemotherapy is one of the essential methods, such as surgery, radiation therapy and immunotherapy, to treat a cancer. However, most of normal cells, especially rapidly dividing cells, are also susceptible to chemotherapeutic agents. Because the side effects resulting from the cytotoxicity to normal cells are unavoidable, many strategies to kill specifically the cancer cells have been developed. The concept of drug targeting and controlled drug delivery is used in an attempt to improve the therapeutic index of drugs by increasing their localization to specific organs, tissues or cells and by decreasing their activity and potential toxic side effects at normal sensitive sites. Liposome is one of them.
Liposomes are colloidal particles of lipid bilayer membranes and are composed of self-assembled amphiphiles (mostly phospholipids) in contact with water.
Different kinds of drugs can be encapsulated in liposomes. Specific antibody molecules can be conjugated with liposome to make an immunoliposome, which can improve the specificity to target cells by specific antigen-antibody interaction.
When the specific antibody conjugated with liposome recognizes antigen on cell surface, the liposome is internalized into cytosol by endocytosis, along with drugs therein. Therefore, drugs can be concentrated selectively to specific target cells and organ using liposome (Huwyler J., Wu D., Pardridge W. M., Brain drug delivery of small molecules using immunoliposomes. Proc. Natl. Acad. Sci. USA 93:14164-14169, 1996; Spragg D., Alford D. R., Greferath R., Larsen C. E., Lee K. D., Gurtner G. C, Cybulsky M. I., Tosi P. F., Nicolau C, and Gimbrone Jr. M. A., Immunotargeting of liposomes to activated vascular endothelial cells: A strategy for site specific delivery in the cardiovascular system. Proc. Natl. Acad. Sci. USA 94:8795-8800, 1997). In this way, it is possible to use immunoliposome in the specific killing of cancer cells when the cancer cells have specific molecules on the surface and produce specific antibody to them.
Local invasion and distant metastasis are the prominent characteristics of malignant tumor cells. High mortality of cancer patients is mostly attributed to those phenotypes.
Several proteases, produced and secreted by normal cells for normal physiological functions, are related to those characteristics of cancer cells. One of the most important proteases expressed by cancer cells is urokinase type plasminogen activator (uPA) (Andreasen P. A., Egelund R., Petersen H.H., The plasminogen activation system in tumor growth, invasion, and metastasis. Cell Mol. Life Sci.51:25- 40, 2000). uPA is a serine protease which activates plasminogen to plasmin and has broad substrate-specificity. Increased expression of uPA from cancer cells leads to marked degradation of extra cellular matrix (ECM). Fig.l is a scheme showing protease involved in pericellular proteolysis for cancer invasion and metastasis.
The expression of uPA is elevated in various cancer tissues such as lung, colon, breast, melanoma removed from patients, The invasiveness of cell line is dependent on the expression of uPA (de Bruin A.F., Grissioen.G.Nerspaget H.W.,
Verheijen J. H., Dooijewaard G., vanden Ingh H.F., Lamers C.B.H.W., Plasminogen activator profiles in neoplastic tissues of the human colon. Cancer Res. 48:4520-4524, 1988; Markus G., Camiolo S. M., Kohga S., Madeja J. M., Mittelman A., Plasminogen activator secretion of human tumors in short-term organ culture, including a comparison of primary and metastatic tumors. Cancer Res. 43:5517-5525, 1983) and it is reported that uPA is expressed highly in the region of growth and invasion of cancer cell (Skriver L., Larsson L. I., Kielberg V., Nielsen L. S., Andresen P. B., Kristensen P., Dano K., Immunocytochemical localization of urokinase-type plasminogen activator in Lewis Lung carcinoma. J. Cell Biol. 99:752-757, 1984). Plasmin generated by uPA activates several MMPs (matrix metalloproteinases), and therefore, accelerates the degradation of laminin and type IV collagen, the components of extracellular matrix (Mackay A. R., Corbitt R. H., Hartzler J. L., Thorgeirsson U. P., Basement membrane type IV collagen degradation: Evidence for the involvement of a proteolytic cascade independent of metalloproteinases. Cancer Res. 50:5997-6001, 1990). Thus, uPA is regarded as a key molecule, which, in turn, means an important target molecule to control the invasion and metastasis of cancer cells. uPA is secreted as inactive single chain form (scuPA) and activated to two chain uPA (tcuPA) (Petersen L. C, Lund L. R., Nielsen L. S., Dano K., Skriver L., One chain urokinase-type plasminogen activator from sarcoma cells is a proenzyme with little or no intrinsic activity. J. Biol. Chem. 263:11189-11195, 1988). In activation of uPA, the receptor of uPA, uPAR is important (Ellis V., Scully M. F., Kakkar, V. V., Plasminogen activation initiated by single-chain urokinase-type plasminogen activator. potentiation by U937 monocyte. J. Biol. Chem. 264:2158-2188 1989). The interaction of uPA and uPAR does not influence on enzymatic activity of uPA and induces co- localization of plasminogen on cell surface, and therefore, accelerated generation of plasmin in pericellular area is expected. The interaction of uPA-uPAR is a key step in the point of co-localization of molecules related in the generation of plasmin, which finally enables cancer cells to degrade extracellular matrix and achieve invasion and metastasis (Danø K., Andreasen P. A., Grøndahl-Hansen K., Kristensen P., Nielsen L. S. Skriver L., Plasminogen activators, tissue degradation and cancer. Adv. Cancer Res. 44: 139-266, 1985; Hollas W., Blasi F., Boyd D., Role of the urokinase receptor in facilitating extracellular matrix invasion by cultured colon cancer. Cancer Res. 51 :3690
- 3695, 1991; Mignatti P., Rifkin D. B., Biology and biochemistry of proteinases in tumor invasion. Physiol. Rev. 73:161-195, 1993; Werb Z., ECM and cell surface proteolysis: regulating cellular ecology. Cell 91 : 439^442, 1997). The invasion and metastasis of cancer cells were down regulated by anti-uPA antibody (Ossowski L., Reich E., Antibodies to plasminogen activator inhibit human tumor metastasis. Cell 35:
611-619, 1983), antisense RNA of uPA (Yu H., Schultz R. M., Relationship between secreted urokinase plasminogen activator activity and metastatic potential in murine B16 cells transfected with human urokinase sense and antisense genes. Cancer Res. 50:7623-7633, 1990), and antisense RNA of uPAR (Kook Y. H., John A., Zelent A., and Ossowski L., The effect of antisense inhibition of urokinase receptor in human squamous cell carcinoma. EMBOJ. 13:3983-3991, 1994).
However, the uPAR bound uPA activity is inhibited by the binding of plasminogen activator inhibitors (PAI). Then, with the binding of α2-macroglobuoin (α2-MR) the complex, uPAR-uPA-PAI, is internalized to cytosol, and the uPA-PAI are degraded. Only the uPAR is recycled on cell surface (Nykjasr A., Conese M.,
Christensen E. I., Olson D., Cremona O., Gliemann J., Recycling of the urokinase receptor upon internalization of uPA: serpin complexes. EMBO J. 16: 2610-2620, 1997). Fig.2 is a scheme showing the internalization of uPAR-uPA-PAI complex into the cytosol and their interaction with α2-MR. As shown in Fig. 2, single chain uPA, secreted as inactive form (A), binds to uPAR and is activated to two chain uPA (B), which forms a complex with PAI and α2-MR (D). The uPAR-uPA-PAI-α2-MR complex is, then, internalized. The uPA and PAI are degraded and only the uPAR and α2-MR molecules are recycled to cell membrane (C). Anti-uPA antibody can initiate internalization (E). This internalization process can be also induced by anti-uPA antibody instead of PAI (Andreasen P. A., Sottrup- Jensen L., Kjøller L., Nykjaer A.,
Moestrup S. K., Munch Petersen C, Receptor mediated endocytosis of plasminogen activators and activator: inhibitor complexes. FEBS Lett. 338: 239-245, 1994; Conese M., Nykjaer A., Petersen C. M., Cremona O., Pardi R., Andreasen P. A., α2- Macroglobulin receptoπLDL receptor related protein (LRP)-dependent internalization of the urokinase receptor. J. Cell Biol. 131 : 1609-1622, 1995; Cubellis M. V., Andreasen P. A., Ragno P., Mayer M., Danø K. Blasi F., Accessibility of receptor- bound urokinase to type- 1 plasminogen activator inhibitor. Proc. Natl. Acad. Sci. USA 86: 4828^1832, 1989; Ellis V., Wun T.C., Behrendt N., Rønne E. Danø K., Inhibition of receptor-bound urokinase by plasminogen activator inhibitors. J. Biol. Chem. 265: 9904-9908, 1990; Nykjasr A., Conese M., Christensen E. I., Olson D., Cremona O., Gliemann j., Recycling of the urokinase receptor upon internalization of uPA:serpin complexes. EMBOJ. 16: 2610-2620, 1997). The internalization of the complex, uPAR-uPA-PAI is a novel target of drug delivery based on the overexpression of uPA in cancer cells and its key role in invasion and metastasis. Furthermore, uPA is also overexpressed in endothelial cells participating in angiogenesis, which is critical for tumor growth. Endothelial cells also utilize proteases including uPA to degrade ECM when they migrate to form new blood vessels.
The growth of tumor may be inhibited by directly killing the cancer cells and by inhibiting the angiogenesis through killing the endothelial cells, which are recruited to make new blood vessels in tumor tissue. Therefore, if a cytotoxic agent is specifically delivered to uPA-overexpressing cells, such as cancer cells and endothelial cells, it will achieve two major goals in the treatment of cancer.
Disclosure of the Invention
It is an object of the present invention to provide a selective drug delivery system targeted to uPA-overexpressing cells such as cancer cells or endothelial cells participating in angiogenesis in cancer tissue.
In accordance with one aspect of the present invention, it is provided a fused cell of myeloma cells and spleen cells of mouse immunized with uPA (urokinase type plasminogen activator), which secretes anti-uPA monoclonal antibody. Preferably, the fused cell is the hybridoma clone, 1E11.
In accordance with another aspect of the present invention, it is provided an anti-uPA monoclonal antibody which is secreted from the fused cell.
In accordance with still other aspect of the present invention, it is provided an immunoliposome conjugated with the anti-uPA monoclonal antibody. Preferably, the immunoliposome includes any drugs or chemical agents such as anticancer drugs, or DNA and contrast media such as fluorescent materials and isotopes, therein.
In the present invention, a novel anti-human uPA monoclonal antibody is produced and conjugated with liposome to make a novel immunoliposome. The anti- uPA immunoliposome of the present invention, in which anticancer drugs are encapsulated, may be used for the specific drug delivery to cancer cells. Hereinafter, the present invention will be described in detail. Although many chemotherapeutic agents of high therapeutic index are continuously developed and used for the treatment of cancer, most of them are toxic not only to tumor cells but also normal cells. Unlike the surgery or radiation therapy the side effect of chemotherapy is not local but systemic. Thus, controlled delivery of the anticancer agents to tumor tissue has been strongly required to increase therapeutic efficacy. For this purpose, the liposomal formulation of anticancer drug was tried
(Gregoriadis G., The carrier potential of liposomes in biology and medicine. N. Engl. J. Med. 295:704-710, 1976; Pagano R.E., Weinstein J.Ν., Interaction of liposomes with mammalian cells. Annu. Rev. Biophys. Bioeng. 7:435-468, 1978; Poste G., Papahadjopoulos D., Drug-containing lipid vesicles render drug-resistant tumour cells sensitive to actinomycin D. Nature 261:699-701, 1976).
Liposome is a micelle composed of phospholipids and amphiphiles. It is similar and can be fused with cellular membrane. When a drug is encapsulated in liposome it can be delivered to cell by the fusion of liposome and cell membrane. Compared to other drug delivery methods, liposome offers several advantages including biocompatibility, low immunogenicity, low toxicity, and a wide range of physical properties that can be modified to control their biological activities (Gerd Bendas, Immunoliposomes: A Promising Approach to Targeting Cancer Therapy. BioDrugs 15(4): 215-224, 2001). Optimal size of liposome depends on the target. In tumor tissues, the vasculature is discontinuous, and fenestration, which is a discontinuous distribution of endothelial cells, varies from 100 to 780 nm in diameter.
By comparison, normal vascular endothelium is 2 nm in most tissues, 6 nm in postcapillary venules, 40-60 nm in kidney glomerulus, and up to 150 nm in sinusoidal epithelium of liver and spleen (Seymour, L. W., Passive tumor targeting of soluble macromolecules and drug conjugates. CRC Crit. Rev. Ther. Drug Carrier Syst., 9: 135- 187, 1992). Therefore, immunoliposomes with the average size of 65-125 nm are small enough to be delivered from blood to target site in tumor tissue across the fenestration.
Early reports have noted that there are problems associated with liposome- mediated drug delivery; removal of liposomes from the circulation by fixed macrophages in reticuloendothelial system (RES), particularly in the liver and spleen. Conventional liposome binds non-specifically to and is fused with cellular membrane, which means a non-specific drug delivery. However, the specificity of liposome can be increased by coating ligands that can recognize cell surface molecules (Martin, F. J., Hubbell W. L., Papahadjopoulos D., Immunospecific targeting of liposomes to cells: a novel and efficient method for covalent attachment of Fab' fragments via disulfide bonds. Biochemistry. 20: 4229-4238, 1981; Martin F. J., Papahadjopoulos D., Irreversible coupling of immunoglobulin fragments to preformed vesicles. An improved method for liposome targeting. Journal of Biological Chemistry. 257: 286- 288, 1982; Martin F., Heath T., New R. Covalent attachment of proteins to liposomes.
In Liposomes, a practical approach. Oxford University Press, New York. 163-182, 1990). One of the ideal molecules is antibody, which is used for immunoliposome.
Immunoliposomes made of specific antibodies or portions of antibodies to tumor cells would be an effective mean of tumor targeting. For this approach, many factors must be taken into consideration, including proper choice of target antigen on the cell surface, antibody specificity, and antibody-liposome linkage (Park, J. W., Hong, K., Kirpotin, D. B., Papahadjopoulos, D., and Benz, C. C, Immunoliposomes for cancer treatment. Adv. Pharmacol., 40: 399^135, 1997). Targeting on tumor cell surface molecules, which shows markedly different pattern of expression profile from normal cells, and making immunoliposome with highly specific antibody against those molecules would be a powerful tool for selective delivery of anticancer drugs.
The present invention achieves this goal by making specific monoclonal antibody against uPA, which is highly expressed in and is a prominent characteristic of malignant tumor cells showing invasion and metastasis. The strategy of immunoliposome targeting on uPA molecule seems to be quite efficient in that the cancer cells can be killed by both direct and indirect pathway. uPA is an enzyme that plays a central role in invasion and metastasis of cancer cells, and therefore, it is a good target for the regulation of invasion and metastasis. However, in addition to the cancer cells there is another important component, which also should be a target for efficient cancer treatment, in tumor tissues. It is the vascular endothelial cell, which is involved in new blood vessel formation for tumor tissues. It is generally known that tumor tissues larger than 1 mm in diameter are unable to be supplied with oxygen and nutrients to the center of the mass. However, it can be overcome by sprouting new vessels, angiogenesis (Bouck N., Stellmach V., Hsu S.C., How tumors become angiogenic. Adv. Cancer Res. 69: 135-74, 1996; Folkman J., Angiogenesis in cancer, vascular, rheumatoid and other disease. Nature Med. 1: 27-31, 1995; Risau W., Mechanisms of angiogenesis. Nature 386:671-674, 1997). Just as the cancer cells do for invasion and metastasis, during the new blood vessel formation vascular .endothelial cell proliferates and moves toward the cancer cells, which need blood vessels. At this stage, endothelial cells should degrade extracellular matrix using various proteases. uPA is one of key molecules in this mechanism (Mignatti P., Rifkin D.B., Plasminogen activators and matrix metalloproteinases in angiogenesis. Enzyme Protein. 49: 117-137, 1996). The expression level of uPA and uPAR is raised by stimulation of angiogenic factors in endothelial cells. It alters extracellular proteolytic activity of endothelial cell (Pepper M. S., Mandriota S. J., Jeltsch M., Kumar V., Alitalo K., Vascular Endothelial Growth Factor (VEGF)-C synergixes with Basic Fibroblast Growth Factor and VEGF in the Induction of Angiogenesis In Vitro and Alters Endothelial Cell Extracellular
Proteolytic Activity. J. Cell. Physi. 177:439-452 1998). Though primary and early subcultures of HUVECs produce only tissue type plasminogen activator (tPA) (Levin, E. G, Latent tissue plasminogen activator produced by human endothelial cells in culture: evidence for an enzyme-inhibitor complex. Proc. Natl. Acad. Sci. U. S. A. 80:6804-6808 1983; van Hinsbergh, V. W. M., Binnema, D., Scheffer, M. A., Spergers,
E. D., Kooistra, T., and Rijken, D. C, Production of plasminogen activators and inhibitor by serially propagated endothelial cells from adult human blood vessels. Arteriosclerosis 7: 389-399 1987), later subcultures of HUVECs also express uPA (Booyse, F. M., Scheinbuks, J., Radek, J., Osikowicz, Feder, S., and Quarfoot, A. J., Immunological identification and comparison of plasminogen activator forms in cultured normal human endothelial cells and smooth muscle cells. Thromb. Res. 24:495-504 1981; Booyse, F. M., Osikowicz, G., Feder, S., and Scheinbuks, J., Isolation and characterization of a urokinase-type plasminogen activator (Mr = 54,000) from cultured human endothelial cells indistinguishable from urinary urokinase J. Biol. Chem. 259:7198-7205 1984; Booyse, F. M., Scheinbuks, J.„ Pei Hua Liu, Traylor and
Robert Bruce., Isolation and Interrelationships of the Multiple Molecular Tissue-Type and Urokinase-type Plasminogen Activator Forms Produced by Cultured Human Umbilical Vein Endothelial Cells. J. Biol. Chem. 263(29): 15129-15138 1988). However, ECGS stimulate to express uPA in in vitro passaged HUVECs. During the angiogenesis, angiogenic factors stimulate endothelial cells to move and invade surrounding tissues, which is largely attributed to the increased expression level of uPA and uPAR. Because the inhibition of angiogenesis will result in the interruption of oxygen and nutrients to tumor mass, anticancer drugs encapsulated in the anti-uPA immunoliposome can indirectly kill tumor cells. In the present invention, the immunoliposome targeting uPA molecule suggests a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway. The key point of anti-uPA immunoliposome is the specificity of anti-uPA atibody, which recognizes bound uPA on the cell surface receptor. The specificity of monoclonal antibody produced by the fused cell of the present invention, preferably IE 11 clone, was confirmed by ELISA, immunoblot and flowcytometry. In addition, specific binding to uPA on uPAR and internalization of their complex into cytosol was clearly shown by confocal microscopy. Encapsulated anticancer drug in immunoliposome showed effective cytotoxicity. Compared to the cytotoxicity of free daunorubicin and liposomal daunorubicin, which is independent of uPA, and therefore, act non-specifically on both cancer cells and normal cells, the immunoliposome showed marked cytoxicity depending on the amount of cell surface uPA. The efficiency of the present immunoliposome was demonstrated with various cell types having different amount of uPA on cell surface. It was noteworthy that leukemic cell lines which are cultivated in suspension, and therefore, have uPA and uPAR uniformly distributed on cell surface are more sensitive than monolayer cells in which uPA and uPAR is located on focal contact area.
Further, other drugs or chemical agents such as contrast media (fluorescent materials and isotopes), and DNA may be included in the immunoliposome of the present invention. For example, DNA is included in the immunoliposome to be delivered to a target cell or tissue for protein expression (or gene therapy). In such gene targeting, lipid of positive charge is used. The immunoliposomes including contrast media (isotopes or fluorescent materials) therein may be used as a probe for a specific site or as a photosensitizer, in which the chemical agents are localized in a specific site and then activated by laser or radiation for the treatment.
Brief Description of the Drawings
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Fig. 1 is a scheme showing protease involved in pericellular proteolysis for cancer invasion and metastasis. Fig.2 is a schemee showing the internalization of uPA-uPAR-PAI complex into the cytosol and their interaction with 2-MR.
Fig. 3 is a graph showing the recognition of uPA on uPAR by anti-uPA monoclonal antibody produced by the hybridoma clone, 1E11.
Fig. 4 is a photograph showing co-localization of anti-uPA immunoliposomes and uPAR in HEp3 cells.
Fig 5 is a photograph showing internalization of anti-uPA immunoliposomes. Fig. 6 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to epidermoid cancer cell lines.
Fig. 7 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to breast cancer cell lines.
Fig. 8 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to leukemia cell lines.
Fig 9 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to ECGS stimulated HUVEC.
Fig. 10 is a photograph showing cell death by treatment of various type of drugs (free drug, liposomal drug, immunoliposomal drug) traced with realtime imaging technique.
Best Mode for Carrying Out the Invention
Hereinafter, the present invention will be described in detail, in conjunction with various examples. These examples are provided only for illustrative purposes, and the present invention is not to be construed as being limited to these examples.
In the Examples, there is described an anti-uPA monoclonal antibody of the present invention, fused cells producing the monoclonal antibody, the immunoliposome conjugated with the monoclonal antibody, and the manufacturing process thereof.
Examples
1. Cell culture
Human cancer cell lines were obtained from the Korean Cell Line Bank (KCLB, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea). The human squamous carcinoma cell lines, HEp3 and SM3, which were transfected with uPAR cDNA to exresses more uPAR than the parent cell, Hep3 (Lyu
M. A., Choi Y. K., Park B. N., Park B. J., Kim B. J., Park I. K, Hyun B. H., Kook Y. H., Overexpression of urokinase receptor in human epidermoid carcinoma cell line (HEp3) increases tumorigenicity on chorioallantoic membrane and in severe combined immunodeficient mice. Int. J. Cancer 77:257-263, 1998), were maintained as monolayer cultures in Dulbecco's modified Eagle medium (DMEM; GIBCO BRL,
Gaithersburg, MD), breast cancer cell lines, MCF-7, MDA-MB-231 and SCC-1395 were maintained as monolayer cultures in Roswell Park Memorial Institute (RPMI)- 1640 (GIBCO BRL, Gaithersburg, MD) and Leukemia cell lines, HL60, K562, Jurkat, THP-1 and U937, were maintained as suspended cultures in Roswell Park Memorial Institute (RPMI-1640, GIBCO BRL, Gaithersburg, MD) supplemented with 10% fetal bovine serum (FBS; GIBCO BRL), 100 units/ml penicillin, and 100 μg/ml streptomycin in a humidified incubator at 37"C and 5% CO2.
2. Manufacturing of anti-uPA monoclonal antibody Balb/c mice (6 weeks old) were immunized with human uPA (Korea Green
Cross Corporation). Each mouse was injected intraperitoneally three times during a period of 9 weeks with 100 μg of the human uPA diluted with either complete or incomplete Freund's adjuvant in the ratio of 1:1. After the third boosting anti-uPA antibody in serum was titrated by ELISA. Two weeks later, the final boosting dose, 100 μg of uPA in 100 μl PBS was given by intravenous injection.
Spleen cells of immunized Balb/c mice were prepared as previously described (Kόhler G., Milstein C, Continuous culture of fused cells secreting antibody predefined specificity. Nature 256:495-498, 1975; Littlefield JW., Selection of hybrids from matings of fibroblasts in vitro and their presumed recombinants. Science 145:709-710, 1964). They were fused with myeloma cells (P3-X63-Ag8.653) by using 50%(w/v) polyethylene glycol (PEG 15000, BM).
Hybridoma clones secreting anti-uPA antibody were screened using indirect ELISA and direct cell ELISA, in which the human uPA and HEp3 cells were coated on the surface of the plate, respectively. A peroxidase-conjugated rabbit anti-mouse immunoglobulin (PROMEGA, USA) and O-phenylenediamine (OPD) were used for enzymatic detection. The optical density (at 492 nm) was measured in an ELISA reader (Titertek Multiscan Flow Laboratories Pty Ltd., Australia). Isotype of antibody was determined using ImmunoPure Monoclonal Antibody Isotyping Kit I (PIERCE, USA) according to manufacturer's instruction.
A hybridoma clone, 1E11, which secrete specific antibody to human uPA was selected to make immunoliposome. Hybridoma cells (5 xlO6 cells/0.5 ml) were injected into the peritoneal cavity of 6-week old Balb/c mice. One or two weeks after the injection, mice were sacrificed and ascitic fluids were harvested to purify anti-uPA monoclonal antibody (IgG) by protein G-Sepharose column (Amersham, USA).
The clone 1E11, which showed strong positive reactivity in indirect ELISA, reactive to surface bound uPA of adherent Hep3 cell, was selected. The culture supernatant of 1E11 was not reactive to tissue type plasminogen activator (tPA) by western blot (data not shown). The isotype of 1E11 antibody was IgGl and K chain.
The hybridoma clone 1E11, as a fused cell secreting a specific antibody to uPA, was deposited with the KCLRF (Korean Cell Line Research Foundation) as accession number KCLRF-BP-00056 on June 5, 2002.
3. Flowcytometry: analysis of uPA and uPAR on cell surface
Specificity of 1E11 antibody to cell surface uPA was examined by flowcytometry.
The amount of uPA and uPAR on cell surface was analyzed by flowcytometry. The cells were detached with trypsin-EDTA, washed with PBS and suspended to be the concentration of 2xl06 cells/ml in PBS with 1% FBS and 0.1% sodium azide.
Antibodies to uPA and uPAR, and anti-human uPAR IgG (American Diagnostica, USA) were diluted (x 200) and added to the cells. Then the cells were incubated at 4°C for 1 hour. After the incubation, cells were washed with PBS and incubated with fluorescein-isothiocyanate (FITC)-conjugated anti-mouse IgG (Cappel, USA) (χ400) at 4°C for 1 hour. The analysis was performed with FACScan flowcytometer (Becton Dickinson, San Jose, CA).
Fig. 3 is a graph showing the recognition of uPA on uPAR by anti-uPA monoclonal antibody produced by the hybridoma clone, 1E11. Compared to the control
(black), the peak of 1E11 antibody (green) was shifted to the right, which shows that 1E1 1 antibody specifically reacted to cell surface uPA. Flowcytometry was also performed to quantitate free uPAR, which was not bound to uPA, after the treatment of cells with excess uPA. The peak of exogenous uPA treated cells (red) was not shifted to the right, suggesting that most of uP AR (blue) on cell surface was pre-occupied with endogenous uPA, which was secreted from cells.
4. Manufacturing of immunoliposome
Liposomes were prepared essentially as previously described (Compagnon, B., Moradpour, D., Alford, D. R., Larsen, C. E., Stevenson, M. J., Mohr, L., Wands, J. R.
& Nicolau, C, Enhanced Gene Delivery and Expression in Human Hepatocellular Carcinoma Cells by Cationic Immunoliposomes. J. Liposome Res. 7: 127-141 1997). Lipids in chloroform were combined at the following ratios: Dioleoylphosphatidylcholine (DOPC, Avanti Polar Lipids) : Cholesterol (SIGMA) : Dioleoylphosphatidylethanolamine-N-[4-(maleimidophenyl)butyrate] ' (MPB-PE,
Avanti Polar Lipids) = 62.5:35:2.5 mol%. Chloroform was removed under vacuum. The lipid mixtures were hydrated in lOmM 4-(2-hydroxyethyl)-l-piperazine ethanesulfonic acid (HEPES), 150 mM ΝaCl and 0.1 mM EDTA (HBSE buffer) for binding studies, or in either 2 mM HEPES, 40 mM 8-hydroxypyrene- 1 , 3, 6-trisulfonic acid (HPTS, SIGMA), 40 mM ΝaCl and 0.1 mM for internalization studies. Lipids were hydrated and frozen and thawed four times, then extruded for 15 cycles through two stacked polycarbonate membranes (pore size 0.1 μm, Corning) using a hand-held extruder (Avanti Polar Lipids). The diameter of liposome (80 to 180 nm) was measured by quasi-elastic light scattering with an Ν4 Plus Submicron Particle Sizer (Coulter). Anti-uPA monoclonal antibody was purified from mice ascites and chemically modified as previously described (Weston P.D. Devries J.A. Wrigglesworth R., Conjugation of enzymes to immunoglobulins using dimeleimides. Biochem. Biophys. Ada 612:40-49, 1980). Purified monoclonal antibody was incubated with succinimidyl- S-acetylthioacetate (SAT A) [solubilized in dimethylformamide at 1 : 10 mol and 100:1 volume ratios (antibody:SATA)] for 30 minutes at room temperature, dialyzed against
50-100 volumes of HBSE buffer changed twice, deacetylated with a 10% (vo vol) addition of deacetylation solution, 50 mM sodium phosphate, 25 mM EDTA, and 0.5 M hydroxylamine (pH 7.5) for 2 hours, and then immediately added to liposomes. The liposome-antibody mixture was gently shaken at 4°C overnight, and then immunoliposomes were separated from free antibody and deacetylation solution by chromatography (Sepharose CL-4B; 1x30 cm; HBSE buffer). Lipid mass was determined by phosphate assay (Chen, P. S., Jr., Toribara, T. Y., Warner, H., Microdetermination of phophorus. Anal. Chem. 28:1756-1758, 1956; Morrison W.R..
A Fast, Simple and Reliable Method for the Microdetermination of Phosphorus in Biological Materials. Analytical Biochemistry. 7:218-224 1964); and protein content was quantified by SDS PAGE.
Daunorubicin-loaded liposome and immunoliposome Lipids were hydrated in 120 mM ammonium sulfate. After extrusion, liposomes were desalted in HBSE buffer by chromatography on Sepharose CL-4B (SIGMA), loaded with daunorubicin HC1 (50-200 mg/ml, 98% pure; SIGMA) as previously described (Haran, G., Cohen, R., Bar, L. K.&Barenholz, Y., Transmembrane ammonium sulfate gradients in liposomes produce efficient and stable entrapment of amphipathic weak bases. Biochim. Biophys. Ada 1151 :201-215, 1993;
Horowitz, A. T., Barenholz, Y. & Gabizon, A. A., In vitro cytotoxicity of liposome- encapsulated doxorubicin: dependence on liposome composition and drug release. (1992) Biochim. Biophys. Ada 1109:203-209, 1992), and then conjugated with anti- uPA antibody. Daunorubicin and lipid concentration was determined by spectrofluorometer (ex. 470 nm; em. 590 nm) and phosphate assay, respectively.
Confocal Microscopy: specific binding and internalization of immunoliposome
Internalization of immunoliposome mediated by the specific binding of anti- uPA antibody and uPA, which was bound to uPAR, was traced by confocal microscopy. To trace the internalization of immunoliposome, HPTS (1-hydroxypyrene-
3,6,8-trisulfonic acid), which is a membrane-impermeant pH-dependent fluorophore (green), was encapsulated in immunoliposome and treated for cancer cells. Color and location of florescence were traced with confocal microscopy (450 nm).
Specifically, HEp3 cells grown on coverslip were washed with phosphate buffered saline and fixed for 10 min in 4% paraformaldehyde in PBS. Fixed cells were rinsed in PBS and then permeabilized with 0.1% Triton X-100 in PBS. Fetal Bovine Serum (10% in PBS) was used to block non-specific binding. The coverslips were incubated with immunoliposome encapsulated with HPTS in PBS for 1 hour at 4°C and incubated at 37 °C for each time. For the staining of nuclei, cells were incubated with propidium iodide (10 mg/ml, SIGMA). After rinsing in PBS, the coverslips were mounted onto glass slides using gelvatol and observed with a confocal laser scanning microscope (Bio-Rad MRC 1024, equipped with a Zeiss Axio-plan microscope). Depending on the cell thickness, 5 to 10 focal frames were taken along the Z-axis at 0.5 mm intervals and then merged to obtain a reconstructed image.
Separately, to detect the cell surface uPAR, Hep3 cells were treated with anti- uPAR antibody (American Diagnostica. USA), incubated at 4°C for 1 hour, and washed three times with PBS. Then cells were treated with secondary antibody, which was conjugated with tetramethyl rhodamine isothiocyanate (TRITC, SIGMA).
Fig. 4 is a photograph showing co-localization of anti-uPA immunoliposomes and uPAR in HEp3 cells. HEp3 cells treated with HPTS-encapsulated anti-uPA immnoliposomes (green fluorescence) and anti-uPAR antibody (red fluorescence) were observed by confocal microscopy as described. Because of the co-localization of both fluorescences, which corresponds to uPA and uPAR, respectively, orange colors are appeared. It suggests the specific binding of immunoliposome to the uPA bound on the cell surface uPAR.
The fate of cell surface-bound immunoliposome was also traced. At the early stage of incubation (30 min at 37°C) granular fluorescences, which corresponds to the dye in immunoliposomes, were observed on the cell membrane.
Fig 5 is a photograph showing internalization of anti-uPA immunoliposomes. After binding on cell surface uPA, most of the granular appearance of green fluorescence in immunoliposomes were introduced and changed to diffusely dispersed fluorescence in the entire cytoplasm, which made the red color of nucleus to orange (30 min). Images viewed by a confocal laser scanning microscope (Bio-rad MRC 1024, equipped with a Zeiss Axio-plan microscope) at ex=488 nm recorded after 0, 0.5, or 1 hr of incubation at 37°C, respectively (following 30 min liposome pre-incubation at 4°C and washing). With the prolonged incubation (60 min at 37°C), most of the granular appearance of green fluorescence were introduced into the cytosol and changed to diffusely dispersed fluorescence in the entire cytoplasm, which made the red color of nucleus to orange.
5. Cytotoxicity assay: anticancer drug delivered by immunoliposome Immunoliposome encapsulated with anticancer drug, daunorubicin was made and used to kill cultured cancer cells. HEp3 and SM3, which was transfected with uPAR cDNA, and therefore, held more uPA on cell surface than Hep3, were compared.
The XTT assay kit (Boehringer Mannheim, Indianapolis, IN) was used for the cytotoxicity assay. Cells (1 x 104/well) were plated into 96-well tissue culture plates. After 24 hours, cultured cells were treated with varying concentrations of daunorubicin in free, liposomal, and immunoliposomal form, and then incubated. Then, 50 μl of XTT solution was added to the culture and incubated for 4 hours. The absorbance was measured at 450 nm using a microplate reader (Dynatech, Chantilly, VA). The viability of leukemic cell lines was determined by [methyl- H]-thymidine incorporation assay. Cells were labelled with 1 μCi of [methyl-3H]-thymidine (specific activity of 6.70 Ci/mmol; Amersham, USA), 18 hours before the harvest by cell harvester (SKATRON semi-automatic cell harvester, Lier, Norway). The radioactivity from incorporated [3H]-thymidine was determined by a liquid scintillation counter
(Beckman LS6500). The results were shown as the mean counts per minute (cpm) of triplicate cell cultures.
Fig. 6 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to epidermoid cancer cell lines. Tumor cells (HEp3 and SM3) expressing different amount of uPAR (a), which means different amount of cell surface-bound uPA, were treated with varying amount of daunorubicin-loaded immunoliposomes for 24 hrs. Compared to the treatment of free daunorubicin (b), anti- uPA immunoliposome showed marked cytotoxicity at the low concentrations of daunorubicin (c). Three different formulations of daunorubicin (free daunorubicinj liposomal daunorubicin and immunoliposomal daunorubicin) were used. After the treatment of free daunorubicin, viability of the HEp3 and SM3 cells similarly decreased in a dose dependent manner. However, compared to the Hep3 cells, the viability of SM3 cells, which expresses more uPAR on cell surface, and therefore, can hold more uPA on cell surface, sharply decreased at low concentration of drug by the treatment of immunoliposome with daunorubicin. It suggests that immunoliposome effectively delivers anticancer drug depending on the number of target molecules.
The survival of breast cancer cell lines (MCF7, MDA-MB-231 and SCC- 1395), which show different levels of uPA and uPAR expression on cell surface, was also tested. Fig. 7 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to breast cancer cell lines. Breast cancer cell lines, which have different amount of uPA and uPAR on cell surface (a), were treated with varying amount of daunorubicin-loaded immunoliposomes. The daunorubicin encapsulated in immunoliposome showed more effective cytotoxicity in those cells that have relatively more uPA on cell surface (HEp3 and MDA MB231) than others (b).
Both of the uPA and uPAR expressions are relatively low and high in MCF7 cells and MDA-MB-231 cells, respectively. However, in SCC-1395 cells uPA expression was low but uPAR expression was higher than MDA-MB-231. Because the MDA-MB-231 cells were more efficiently killed than SCC-1395 at low concentration of daunorubicin, the cytotoxicity mediated by daunorubicin-loaded immunoliposome seemd to be more clearly dependent on the level of uPA than uPAR.
Leukemia and monocyte lineage cell lines, such as HL60, K562, Jurkat, THP- 1, U937, were also tested. Fig. 8 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to leukemia cell lines. Leukemia cell lines, which show different amount of uPA and uPAR (a), were treated with varying amount of daunorubicin-loaded immunoliposomes. The marked cytotoxicity was observed in those cell lines that have more uPA and uPAR (HL60 and THP-1) than other cell lines (b).
These cell lines also show different level of uPA and uPAR expression on the cell surface. The cytotoxic effect of daunorubicin-loaded immunoliposome was also more dependent on the level of uPA than uPAR expression. At low concentration of daunorubicin-loaded immunoliposome, it was more effective in cells having more uPA on cell surface.
Human umbilical vein endothelial cell (HUVEC) was also tested. During the in vitro passage of HUVEC, endothelial cell growth supplement (ECGS) added to culture can induce more expression of uPA. Fig 9 is a graph showing in vitro cytotoxicity of daunorubicin in anti-uPA immunoliposome to ECGS-stimulated HUVEC. HUVEC has comparable amount of uPA and uPAR as HEp3 cell (a). Similar patterns of cytotoxicity were observed in both cell lines (b). The treatment of daunorubicin-loaded immunoliposome on HUVEC showed similar cytotoxicity with HEp3.
The process of cell death after the treatment of three different formulations of daunorubicin was traced by real time imaging technique. Cells treated with free daunorubicin started to show necrotic features at 2 hours. On the contrary, daunorubicin in liposome and immunoliposome killed the cells via apoptotic pathway, which started after 10 hours, and showed typical features of membrane blgbbing and apoptotic body. Fig. 10 is a photograph showing cell death by treatment of various type of drugs (free drug, liposomal drug, immunoliposomal drug) traced with realtime imaging technique.
As described above, the immunoliposome targeting uPA molecule suggests a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway. The key point of anti-uPA immunoliposome is the specificity of anti-uPA atibody, which recognizes bound uPA on the cell surface receptor. The specificity of monoclonal antibody produced by the fused cell of the present invention, preferably IE 11 clone, was confirmed by ELISA, immunoblot and flowcytometry. In addition, specific binding to uPA on uPAR and internalization of their complex into cytosol was clearly shown by confocal microscopy. Encapsulated anticancer drug in immunoliposome showed effective cytotoxicity. Compared to the cytotoxicity of free daunorubicin and liposomal daunorubicin, which is independent on uPA, and therefore, acts non-specifically on both cancer cells and normal cells, the immunoliposome showed marked cytoxicity depending on the amount of cell surface uPA. The efficiency of the present immunoliposome was demonstrated i h various cell types having different amount of uPA on cell surface. It was noteworthy that leukemic cell lines which are cultivated in suspension, and therefore, have uPA and uPAR uniformly distributed on cell surface are more sensitive than monolayer cells in which uPA and uPAR is located on focal contact area.
Industrial Applicability
As apparent from the above description, the anti-uP A immunoliposome of the present invention is one of the possible candidates of efficient drug delivery system to uPA over-expressing cancer cells that may show malignant behavior, such as local invasion and metastasis. Anticancer drugs encapsulated in the anti-uPA immunoliposome can not only directly kill tumor cells but also indirectly kill tumor cells by the interruption of oxygen and nutrients to tumor mass, which can be achived by killing the endothelial cells involved in angiogenesis. Therefore, the immunoliposome targeting uPA molecule may provide a novel strategy for cancer chemotherapy in that the cancer cells can be killed by both direct and indirect pathway.
BUOΛI'KST TREATY ON THE IN ERNATIONAL
RECOGNITION OF THE DEPOSIT OF MICROORGANISMS
FOR THE PURPOSE OF PATENT PROCEDURE
INTERNATIONAL FORM
RECEPTION IN THE CASE OF AN ORIGINAL DEPOSIT issued pursuant to Rule 7.1
To: Yoon-Hoh Kook
Hyun-Dai Apt. 106-703, 653,
Gaepo-Dong, Kangnam-Gu,
Seoul 135-240, KOREA
I. IDENTIFICATION OF THE MICROORGANISM
identification reference given by the Accession number given by the INTERNATIONAL DEPOSITARY DEPOSITOR : lull AUTHORITY:
KCLRF.BP-00056
II. SCIENTIFIC DESCRIPTION AND/OR PROPOSED TAXONOMIC DESIGNATION
The microorganism identified under I above was accompanied by
[ } A scientific description
[ ] A proposed taxonomic designation
(Mark with a cross where applicable)
III. RECEIPT AND ACCEPTANCE
This International Depositary Authority accepts the microorganism identified under I above, which was received by it on June 5, 2002
IV. INTERNATIONAL DEPOSITARY AUTHORITY
Name : Director
Korean Cell Line Research Signature(s) ; Foundation
Figure imgf000018_0001
Address : Cancer Research Institute Date : 2002. 6. 22 Seoul National University College of Medicine 28 Yongon-dong, ChongDO-Gu Seoul, 110-744, Korea
Foi'm BP/4 (KCLRF βrm 17) P-Jt soli

Claims

Claims:
1. A fused cell of myeloma cells and spleen cells of mouse immunized with uPA (urokinase type plasminogen activator), which secretes anti-uPA monoclonal antibody.
2. The fused cell of claim 1, which is the hybridoma clone, 1E1 1 (KCLRF- BP-00056).
3. An anti-uPA monoclonal antibody which is secreted from the fused cell of claim 1.
4. An immunoliposome conjugated with the anti-uPA monoclonal antibody of claim 3.
5. The immunoliposome of claim 4, which includes a drug or chemical agent therein.
6. The immunoliposome of claim 5, wherein the drug or chemical agent is anticancer drugs, DNA or contrast media.
PCT/KR2003/001233 2002-06-27 2003-06-24 Immunoliposome conjugated with anti-upa antibody WO2004003183A1 (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1691664A2 (en) * 2003-11-18 2006-08-23 Attenuon, LLC Antibodies and/or conjugates thereof which bind to the amino terminal fragment of urokinase, compositions and uses thereof
US8105602B2 (en) 2006-12-08 2012-01-31 Tactic Pharma, Llc Urokinase-type plasminogen activator receptor epitope, monoclonal antibodies derived therefrom and methods of use thereof
US8138313B2 (en) 2007-06-15 2012-03-20 Deutsches Krebsforschungszentrum Stiftung Des Offentlichen Rechts Treatment of tumors using specific anti-L1 antibody
WO2014120555A1 (en) * 2013-01-31 2014-08-07 The Regents Of The University Of California Antibodies specific for urokinase-type plasminogen activator and methods of use thereof
US9309325B2 (en) 2009-05-07 2016-04-12 The Regents Of The University Of California Antibodies and methods of use thereof
WO2018115485A1 (en) 2016-12-22 2018-06-28 Pierfrancesco Tassone A monoclonal antibody targeting a unique sialoglycosilated cancer-associated epitope of cd43
US10400037B2 (en) 2014-09-30 2019-09-03 Deutsches Krebsforschungszentrum Stiftung des öffentlichen Rechts Binding molecules, especially antibodies, binding to L1CAM (CD171)
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4708933A (en) * 1984-06-12 1987-11-24 Leaf Huang Immunoliposome assay-methods and products
US4925661A (en) * 1984-04-19 1990-05-15 Leaf Huang Target-specific cytotoxic liposomes
US4957735A (en) * 1984-06-12 1990-09-18 The University Of Tennessee Research Corporation Target-sensitive immunoliposomes- preparation and characterization
JPH09110722A (en) * 1995-10-20 1997-04-28 Toray Ind Inc Immunoliposome for transducing tumorous cell of antitumor active substance and its preparation
WO1997038731A1 (en) * 1996-04-18 1997-10-23 The Regents Of The University Of California Immunoliposomes that optimize internalization into target cells

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8604851D0 (en) * 1986-02-27 1986-04-03 Lepetit Spa Immunosorbent-amidolytic method
IT1228881B (en) * 1988-08-12 1991-07-09 Lepetit Spa SPECIFIC MONOCLONAL ANTIBODY FOR THE EPITOPE OF THE UROKINASIS PROURICHINASI CORRESPONDING TO THE REGION DENOMINATED GFD
CN1198590C (en) * 1999-04-23 2005-04-27 三菱化学株式会社 Antibody and polyalkylene glycol-bonded liposome

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4925661A (en) * 1984-04-19 1990-05-15 Leaf Huang Target-specific cytotoxic liposomes
US4708933A (en) * 1984-06-12 1987-11-24 Leaf Huang Immunoliposome assay-methods and products
US4957735A (en) * 1984-06-12 1990-09-18 The University Of Tennessee Research Corporation Target-sensitive immunoliposomes- preparation and characterization
JPH09110722A (en) * 1995-10-20 1997-04-28 Toray Ind Inc Immunoliposome for transducing tumorous cell of antitumor active substance and its preparation
WO1997038731A1 (en) * 1996-04-18 1997-10-23 The Regents Of The University Of California Immunoliposomes that optimize internalization into target cells

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* Cited by examiner, † Cited by third party
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EP1691664A4 (en) * 2003-11-18 2008-04-30 Attenuon Llc Antibodies and/or conjugates thereof which bind to the amino terminal fragment of urokinase, compositions and uses thereof
US8105602B2 (en) 2006-12-08 2012-01-31 Tactic Pharma, Llc Urokinase-type plasminogen activator receptor epitope, monoclonal antibodies derived therefrom and methods of use thereof
US9260521B2 (en) 2007-06-15 2016-02-16 Medigene Ag Treatment of tumors using specific anti-L1 antibody
US8138313B2 (en) 2007-06-15 2012-03-20 Deutsches Krebsforschungszentrum Stiftung Des Offentlichen Rechts Treatment of tumors using specific anti-L1 antibody
US9309325B2 (en) 2009-05-07 2016-04-12 The Regents Of The University Of California Antibodies and methods of use thereof
WO2014120555A1 (en) * 2013-01-31 2014-08-07 The Regents Of The University Of California Antibodies specific for urokinase-type plasminogen activator and methods of use thereof
US9255155B2 (en) 2013-01-31 2016-02-09 The Regents Of The University Of California Antibodies specific for urokinase-type plasminogen activator and methods of treating cancer
US9695249B2 (en) 2013-01-31 2017-07-04 The Regents Of The University Of California Antibodies specific for urokinase-type plasminogen activator and methods of use thereof
US10239954B2 (en) 2013-01-31 2019-03-26 The Regents Of The University Of California Antibodies specific for urokinase-type plasminogen activator and methods of use thereof for treating cancer
US10400037B2 (en) 2014-09-30 2019-09-03 Deutsches Krebsforschungszentrum Stiftung des öffentlichen Rechts Binding molecules, especially antibodies, binding to L1CAM (CD171)
WO2018115485A1 (en) 2016-12-22 2018-06-28 Pierfrancesco Tassone A monoclonal antibody targeting a unique sialoglycosilated cancer-associated epitope of cd43
US11174318B2 (en) 2016-12-22 2021-11-16 Università Degli Studi Magna Graecia Catanzaro Monoclonal antibody targeting a unique sialoglycosylated cancer-associated epitope of CD43
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