IL93067A - Chimeric non-human mammal - Google Patents

Chimeric non-human mammal

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Publication number
IL93067A
IL93067A IL9306790A IL9306790A IL93067A IL 93067 A IL93067 A IL 93067A IL 9306790 A IL9306790 A IL 9306790A IL 9306790 A IL9306790 A IL 9306790A IL 93067 A IL93067 A IL 93067A
Authority
IL
Israel
Prior art keywords
mammal
cells
scid
agent
chimeric
Prior art date
Application number
IL9306790A
Other versions
IL93067A0 (en
Inventor
Yair Reisner
Original Assignee
Yeda Res & Dev
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to IL9306790A priority Critical patent/IL93067A/en
Application filed by Yeda Res & Dev filed Critical Yeda Res & Dev
Publication of IL93067A0 publication Critical patent/IL93067A0/xx
Priority to DE69131331T priority patent/DE69131331T2/en
Priority to EP91100047A priority patent/EP0438053B1/en
Priority to DK91100047T priority patent/DK0438053T3/en
Priority to IL9712891A priority patent/IL97128A/en
Priority to IL9836991A priority patent/IL98369A/en
Priority to US08/061,706 priority patent/US5652373A/en
Priority to IL10694993A priority patent/IL106949A/en
Priority to US08/347,088 priority patent/US5709843A/en
Priority to US08/475,584 priority patent/US5849288A/en
Publication of IL93067A publication Critical patent/IL93067A/en

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Description

93067/3 DTK w>HV \yrn ηα )i> A novel chimeric non-human mammal lit"-* Ί>Ν> :N^o>on The inventor: Yair REISNER »"u nina npnn man > YEDA RESEARCH AND DEVELOPMENT COMPANY LIMITED C: 91335\0 Field of the Invention; The invention relates to the production of certain novel mammals and to assays based on the use of these. Furthermore the invention relates to the use of sera or other products derived from such mammals for assays, immunization and therapy of certain disorders and diseases .
The invention is based on the production of certain novel types of mammals , and more particularly of chimeric mammals of the mouse-human, horse-human etc. chimera type, which are characterized by having human type lymphocytes, such as T-cells and the like.
The novel chimeric animals can be infected with a variety of diseases, such as for example AIDS etc. and can be used for the evaluation of certain substances as to their efficiacy as drugs against this, and other diseases.
Background of the Invention; Human immunodeficiency virus type 1 (HIV-1) is etiologically associated with acquired immune deficiency syndrome (AIDS).
Recently, an additional retrovirus, termed HIV-2 [related to HIV-1 but more so to some strains of simian immune deficiency virus ( SIV) ] was isolated from sick and healthy individuals . Current seroepidemiological and laboratory studies suggest that although some HIV-2 isolates are associated with AIDS other may be far less pathogenic.
Chimpanzees and gibbon apes are the only animals that can be experimentally infected with HIV-1 isolated from AIDS patients, yet the virus does not appear to cause lethal diseases in these primates , as it does in man . Macaques , chimpanzees and goats who have been actively immunized either with the virus or with viral proteins, consistently exhibits immune responses to specific HIV-1 antigens in vitro. Moreover, specific humoral and cellular immune responses towards envelope and core proteins HIV-1 were demonstrated recently in gibbon apes chronically infected with HIV-1. The specific T cell reactivity toward HIV-1 proteins observed in infected gibbons contrasts with the lack of such responses in HIV-1 infected humans, and may help to explain the resistance of primates to the development of AIDS after infection with HIV-1.
Successful xenogenic bone marrow transplants between different species such as rat to mouse, mouse to rat and human to mouse have been demonstrated. Two major conditions must be fulfilled if transplanted bone marrow is to be engrafted: 1) prevention of graft vs. host disease, which is caused by donor T cells present in bone marrow inoculum, and 2) adequate immunosuppression of the bone marrow recipient.
There have clearly been demonstrated satisfactory techniques (such techniques are already available) to deplete T cells from bone marrow of different species, including primates. As a result, it is possible to avoid the development of graft vs. host disease .
Adequate immunosuppression of a bone marrow recipient infected with AIDS may be achieved because the immune system of AIDS patients may be unable to mount a significant attack against donor HLA antigens, which would normally lead to a rejection of the bone marrow transplant. However, a mild immunosuppressive therapy with drugs such a cyclophosphamide to ATG may be required to ensure engraftment of mismatched T cell-depleted bone marrow, as was found to be the case in some Severe Combined Immune Deficiency Disease (SCID) patients.
Very recently, several groups have demonstrated that the use of genetically determined immune deficient mice, such as the SCID mouse or the Bg/Nu/Xid mouse, enabled engraftment of human T lymphocytes without apparent graft-versus-host disease. However, these xenotransplants were imperfect.
When Bg/Nu//Xid mice were used as bone marrow recipients, only myeloid engraftment was detected, while T cells failed to engraft. The myeloid engraftment was only partial and transient.
When SCID mice were used as bone marrow recipients, two types of mouse-human chimeras were produced. In one appr^ ch Mosier and colleagues injected human peripheral blood lymphocytes into such mice. Surprisingly, the presence of these lymphocytes could be detected in the peripheral blood of recipients several weeks later, without causing clinical manifestations of graft-versus-host disease. Although these mice cannot serve as models for human T cell differentiation, they have been shown to afford reasonable models for AIDS research, as the human T cells present in peripheral blood can be infected with HIV-1.
Studies undertaken by Weissman et al., (Science 241:1632, (1988) and Science 242:1684 (1988)) suggested that differentiation of human cells into mature T cells cannot occur in murine thymic epithelium, and therefore, they developed a complicated and difficult method to create mouse-human T cell chimeras. This second approach, which also made use of SCID mice as bone marrow recipients, involved transplantation of both human fetal thymic epithelium and fetal liver cells , the latter servinc as a source of hematopoietic stem cells void of graft-verus-host disease. This cumbersome procedure was necessary since a translplant of fetal liver ceils alone did not engraft. However, r it was demonstrated that transient differentiation of T cells could occur in the transIplanted human epithelium, thereby leading to the transient appearance of human T cells in peripheral blood or in the spleen. As in the former approach, this transient appearance of human T ceils was enough to allow successful infection of mice with HIV.
The procedure of Weissman has certain drawbacks. Human T-celis growing in mouse thymus of the recipient mammal should be tolerant to the tissues of the recipient. According to his procedure T cells develop in human epithelial thymus tranplanted with human fetal liver cells, and thus cannot be expected to be tolerant towards mouse tissues .
SiTnrmairy of the Invention: The present invention provides a method for the production of a chimeric mammal having T cells of a desired mammal M^, comprising implanting bone marrow taken from a Severn Combined Immune Deficiency Disease (SCID) donor to a genetically compatible mammal Mj which has been irradiated so as to essentially destroy its immune system, and simultaneously or with a short time lag implanting said animal Mj with T cell depleted bone marrow, without graft vs. host (GVH) activity, of the mammal M- resulting in a chimera M4 having M3 mammal B and T cells.
By one of its embodiments the invention provides a method for evaluating the efficacy of an agent, treatment modality or a combination thereof in the therapy of a hematopoietic related disease or disorder comprising: (a) infecting a chimeric mammal as defined above with an infective material capable of causing a hematopoietic related disease or disorder, resulting in an infected chimeric mammal M^ (b) administering said agent, treatment modality or a combination thereof to said infected chimeric mammal M5; and (c) testing for the presence or amount of said infective material in a body fluid or a tissue of said infective chimeric mammal M, and for the presence of hematopoietic disease or disorder related symptoms in said chimeric mammal M5, wherein the efficacy of the agent, treatment modality or combination thereof is inversely related to the amount or presence of the said infective material or to the presence of said disease or disorder related symptoms, thereby evaluating the efficacy of the agent, treatment modality or combination thereof.
By yet another of its embodiments the invention provides a method for evaluating the efficacy of an agent, treatment modality or combination thereof in the therapy of leukemia, comprising: (a) producing a chimeric mammal M4 as defined above wherein the B and/or T cells of said mammal 4, derived from mammal M3, are leukemia cells; (b) administering said agent, treatment modality or a combination thereo to said chimeric mammal M4; and .. . (c) monitoring the number of leukemia cells in said chimeric mammal, wherein the efficacy of the agent, treatment modality or combination thereof is inversely related to the number of said leukemia cells in said chimeric mammal, thereby evaluating the efficacv of said agent, treatment modality or a combination thereof.
An objective of this invention is to create a mouse and other chimera in which blood cells are of host type, except for 4a and B cells, which will be of human or simian origin. This goal can be attained in normal mice by conditioning animals with lethal TBI, and subsequently transplanting them with bone marrow from different donors: SCID mouse bone marrow to reconstitute hematopoiesis except in the T and B cell lineages, and human bone marrow which produces the latter cell types upon differentiation in the new host.
In such SCID type mammals the thymus epithelium is devoid of lymphocytes due to a genetic deficiency in stem cells which produce both red and white cells, and other blood cells of the various types . Such stem cells are present in the bone marrow, and it is a characteristic of these that when blood cells are produced, the number of stem cells in the bone marrow remains nearly constant. Such pluripotent stem cells serve as efficient source of all blood cells, including the lymphoid lineage comprising both B and T type lymphocytes. In SCID type animals the pre-B and the pre-T, as well as the resulting T cells and B cells are deficient and do not undergo cell division in the thymus. As an order of magnitude: in the thymus of normal mice there are present about 20-30xlOs cells, whereas in SCID lines there are present only about 500,000 such cells.
When a mouse is used, which has undergone adequate irradiation, and stem cells are implatned, stem cells of human origin take quite a long time to generate the required blood cell supply.
According to the present invention an entirely novel process for the production of animal/human chimeras, with human T cell population is, provided. 5 r sen nven on e one marrow of a SCID type animal (mouse, horse etc.) is used as bone marrow donor. The recipient is a normal mouse (or SCID mouse),, and the implant is made after the immune system of the recipient is destroyed bv irradiation. Simultaneously, or shortly before or after implantat'ion of the animal bone marrow, human bone marrow is implanted into the recipient mouse which is T cell depleted and essentially devoid of GVH (graft versus host) activity. It is clear that a gentically suitable strain of mice is to be used (donor/recipient) . A few weeks after such implant (twice) the result is a normal mouse, with all systems including blood components, except for T cells, which are essentially only human T cells.
Contrary to normal mice, due to the presence of human T cells such mice can be infected with AIDS (HILV) virus, and with any other type of virus which infects humans but does not normally infect mice. There exists a wide variety of suitable SCID mouse strains, and there are also avaible SCID horse types.
In a similar manner SCID bone marrow can be implanted in a genetically suitable irradiated mouse, resulting ultimately in a chimera having all the characteristics of a mouse, but only monkey T cells .
The novel strains of animals are of value in research and development. They make possible reproducible studies of the mechanism of various hematopoietic diseases or disorders and are useful in evaluating the efficacy of an agent, treatment modality or a combination thereof in the therapy of such diseases or disorders.
One example of such a hematopoietic disease or disorder is AIDS, wherein the chimera in accordance with the invention can be easily infected by the AIDS irus (of 6 human type) and then treated wi th a variety of agents, thus sa ing their efficacy asair.s this and similar virus types and strains.
In a similar manner it is possible to produce chimeric animals (mice, horses etc.) with human T cell leukemia cells etc. This is readily done by transplanting SCID bone marrow to an irradiated recipient (e.g. mouse), parallel with the implant of human bone marrow of a patient ill with T cell leukemia or B cell leukemia. Such chimera are of considerable value in reseach and in the development of methods of treatment and development of pharmaceuticals againt these diseases . Thus the invention also relates to assays of this type, using chimera of the novel type set our above.
The growing experience with human bone marrow transplants shows that differentiation of human stem cells into T cells takes 2-4 months, as opposed to such stem cell differentiation in mice, which takes about 10 days . In mice whose immune systems are heavily suppressed, survival without a bone marrow transplant is limited to at most 2 weeks, due to hematological death. Thus, even if human cells can theoretically grow in mice and reconstitute the hematopoietic system, their slow rate of differentiation might prevent them from reaching large enough numbers so as to protect the mice form hematopoietaic death associated with total body irradiation (TBI). On the other hand, sublethal conditioning protocols which spare substantial numbers of murine stem cells and leukocytes, enables such cells to compete very effectively with a human transplant, and reject it.
According to the invention, use is made of SCID mice as bone 7 marrow donors rather than as bone marrow recipients , in order to promptly reconstitute all hematopoietaic lineages except the T and B cell lineages, which cannot develop from SCID pluripotent stem cells due to a deficient rearrangement of antigen receptor genes. This "empty space" in the thymus will be occupied by any other normal stem cells from any possible species. Therefore, there is combined the transplant of SCID bone marrow with a transplant of T cell-depleted human bone marrow. Thus, about one hour after transplantation of SCID bone marrow into 10 Gy TBI-treated BALB/c mice (BALB/c mice are H-2 identical with SCID mice), T cell-depleted human bone marrow cells are transplanted. The prompt differentiation of the SCID stem cells leads to prolonged survival of such animals, long enough to provide the time required for the differentiation of human stem cells into T cells .
We were able to achieve a mouse-human chimera on the average in one mouse out of five tested (Fig. 1). In such mouse-human chimera, which were tested 30 days post-transplant, 25% of peripheral blood lymphocytes were human T cells stained with a specific Pan-T monoclonal antibody, anti-Leu 4 (Fig. IB), compared to 66% stained among human peripheral blood lymphocytes (Fig. 1A) and 0.9% stained among murine peripheral blood lymphocytes (taken from a mouse that failed to engraft with human bone marrow cells) (Fig. 1C) .
A major problem in using normal BALB/c recipients is that a substantial number of host type thymocytes still remain in the mice even after animals are conditioned with 10 Gy TBI. We have found that the radiation dose can be escalated to 11 Gy. , without 8 a significant reduction in survival rates, if fully allogeneic bone marrow cells are used. Further refinement of the condition protocol can be achieved by using 10 Gy TBI plus specific booster irradiation to the thymic area.
According to the invention it is possible to create a sufficient number of mouse-human chimeras, as well as mouse-monkey and mouse-hamster chimeras, to proceed to evaluation of the susceptibility of the various chimeras to the AIDS virus .
Mice Animals used are 8-12 week old female BALB/c and male SCID mice obtained from Roscoe B. Jackson Memorial Laboratory, Bar Harbor, Maine. All mice are kept in small cages (5 animals in each cage) and fed sterile food and acid water.
Irradiation Mice are exposed to a single dose of 10 Gy TBI from a Gamma beam 150-AsoCo source (produced by the Atomic Energy of Canada) with F.S.D. of 75 cm and at a 0.7 Gy/min dose rate.
Preparation of murine T cell depleted bone marrow cells Murine bone marrow cells are prepared according to Reisner et al., (Proc. Natl.Acad.Aci. USA 75:2933 (1978), with minor modifications (Schwartz et al . , J. Immunol. 138:469. (1987).
Preparation of tinman T cell-depleted bone marrow cells Human bone marrow cells are prepared as described by Reisner et al., (Lancet 2:327 (1981) using differential agglutiniation with soybean agglutinin (SBA) followed by E-rosetting with sheep red blood cells .
Blood testing Mice are bled from the retro-orbital veins using heparin- coated glass capillaries. Blood samples are counted (Coulter Counter S+II, Coulter Electronics, Luton, England).
Chimerism analysis Mice are bled as described above, and mononuclear cells are purified by Ficoll-Hypaque fractionation. Cells are washed twice with PBS, and stained with monoclonal antibodies specific for human or mouse T cell markers. These include anti-Leu 2, anti-Leu 3, anti-Leu 4, anti-Leu 5, ante-Leu 7 and ant-Leu 11 for human cells, and anti-Lyt 2, anti L3T4, anti-H2el and anti-Thyl .2 for mouse cells . The relative staining of the chimeric cells with each antibody is recorded in a fluorescence-activated cell sorter, and the threshold for positive staining is such that the number of cells stained with the second antibody alone does not exceed 10%. 10

Claims (8)

- 11 - 93067/4 CLAIMS:
1. A method for the production of a chimeric mammal M4 having T cells of a desired mammal M3, comprising implanting bone marrow taken from a Severe Combined Immune Deficiency Disease (SCID) donor M2 to a genetically compatible mammal M2 which has been irradiated so as to essentially destroy its immune system, and simultaneously or with a short time lag implanting said animal Mj with T cell depleted bone marrow, without graft vs. host (GVH) activity, of the mammal M3 resulting in a chimera M4 having M3 mammal B and T cells.
2. A method according to Claim 1, wherein the SCID donor M2 is a SCID mouse, the recipient M1 is a genetically acceptable mouse, and the mammal M3 is a human.
3. A method according to Claim 1, wherein the SCID donor M2 is a SCID mouse, the recipient M1 is a genetically acceptable mouse, and the mammal M3 is a monkey.
4. A method according to Claim 1, wherein the SCID donor M2 is a SCID horse, the recipient Ma is a normal or a SCID horse being genetically compatible with donor M2, and the mammal M3 is a human.
5. A method according to Claim 1, wherein mammal M3 is a human leukemia patient.
6. A method for evaluating the efficacy of an agent, treatment modality or a combination thereof in the therapy of a hematopoietic related disease or disorder comprising: (a) infecting a chimeric mammal M4 according to any one of Claims 1-4 with an infective material capable of causing a hematopoietic related disease or disorder, resulting in an infected chimeric mammal M5; - 12 - 93067/4 (b) administering said agent, treatment modality or a combination thereof to said infected chimeric mammal Ms; and (c) testing for the presence or amount of said infective material in a body fluid or a tissue of said infective chimeric mammal M5 and for the presence of hematopoietic disease or disorder related symptoms in said chimeric mammal M5, wherein the efficacy of the agent, treatment modality or combination thereof is inversely related to the amount or presence of the said infective material or to the presence of said disease or disorder related symptoms, thereby evaluating the efficacy of the agent, treatment modality or combination thereof.
7. A method according to Claim 6, wherein the hematopoietic related disease is AIDS and said infective material is an HIV-related virus.
8. A method for evaluating the efficacy of an agent, treatment modality or combination thereof in the therapy of leukemia, comprising: (a) producing a chimeric mammal M4 in accordance with Claim 5, wherein the B and/or T cells of said mammal M4, derived from mammal M3, are leukemia cells; (b) administering said agent, treatment modality or a combination thereof to said chimeric mammal M4; and (c) monitoring the number of leukemia cells in said chimeric mammal, wherein the efficacy of the agent, treatment modality or combination thereof is inversely related to the number of said leukemia cells in said chimeric mammal, thereby evaluating the efficacy of said agent, treatment modality or a combination thereof. For the Applicants, DR. REINHOLD COHN AND PARTNERS 91335-0-aaims¾G be/26.3.1995
IL9306790A 1990-01-15 1990-01-15 Chimeric non-human mammal IL93067A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
IL9306790A IL93067A (en) 1990-01-15 1990-01-15 Chimeric non-human mammal
DE69131331T DE69131331T2 (en) 1990-01-15 1991-01-02 Permanent transplantation and development of human hematopoietic cell lines in normal mammals
EP91100047A EP0438053B1 (en) 1990-01-15 1991-01-02 Durable engraftment and development of human hematopoietic lineages in normal mammals
DK91100047T DK0438053T3 (en) 1990-01-15 1991-01-02 Sustained transplantation and development of human hemopoietic cell lines in normal mammals
IL9712891A IL97128A (en) 1990-01-15 1991-02-01 Method for production of human monoclonal antibodies in non-human chimeric mammals
IL9836991A IL98369A (en) 1990-01-15 1991-06-04 Production of a chimeric mammal having xenogeneic cells and tissue
US08/061,706 US5652373A (en) 1990-01-15 1993-05-17 Engraftment and development of xenogeneic cells in normal mammals having reconstituted hematopoetic deficient immune systems
IL10694993A IL106949A (en) 1990-01-15 1993-09-08 Development of xenogeneic cytotoxic t lymphocytes in non-human mammals
US08/347,088 US5709843A (en) 1990-01-15 1994-11-23 Engraftment and development of xenogeneic cells in normal mammals having reconstituted hematopoietic deficient immune systems
US08/475,584 US5849288A (en) 1990-01-15 1995-06-07 Method for production of monoclonal antibodies in chimeric mice or rats having xenogeneic antibody-producing cells

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IL9306790A IL93067A (en) 1990-01-15 1990-01-15 Chimeric non-human mammal

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IL93067A0 IL93067A0 (en) 1990-11-05
IL93067A true IL93067A (en) 1995-12-31

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IL9836991A IL98369A (en) 1990-01-15 1991-06-04 Production of a chimeric mammal having xenogeneic cells and tissue

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CN110810323B (en) * 2019-04-23 2021-09-14 中国科学院脑科学与智能技术卓越创新中心 Method for preparing non-human primate model with compulsive ceremonial behavior

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IL93067A0 (en) 1990-11-05
IL98369A (en) 2004-06-20
IL98369A0 (en) 1992-07-15

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