IMMUNOBIOLOGY OF PANCREATIC ISLET XENOGRAFTING

胰岛异种移植的免疫生物学

• 批准号: 2466376
• 负责人: Ronald G Gill
• 金额: $ 18.53万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2466376
• 关键词: MHC class II antigen; SCID mouse; T lymphocyte; antigen presenting cell; apoptosis; athymic mouse; cellular immunity; cytolysins; gene targeting; genetically modified animals; helper T lymphocyte; inflammation; interferon gamma; laboratory rat; leukocyte activation /transformation; leukocyte adhesion molecules; monoclonal antibody; pancreatic islet transplantation; polymerase chain reaction; pore forming protein; tissue /cell culture; tissue donors; transplant rejection; transplantation immunology; xenotransplantation

DESCRIPTION: (Adapted from the applicant's abstract) The goal of the proposed research is to study the basis of T cell-mediated immune recognition of xenogeneic cellular grafts, using islets of Langerhans as a relevant model system. Data obtained during the funding period strongly suggests that the prevalent mode of xenogenic islet recognition is through the indirect pathway of antigen recognition by recipient's CD4+ T lymphocytes. In Specific Aim I a, several immunodeficient mice will be used to determine the mechanisms of CD4+ T lymphocyte-dependent xenoreactivity towards rat islets. The notion that islet xenografts survive in nude and SCID recipients strongly suggests that, it least in murine recipients, rejection of such grafts is dependent on T cells. Furthermore, evidence was obtained during the first funding period that such cellular response is CD4+ T cell-dependent in vivo. The first goal of this proposal is to analyze the role of molecules involved in target cell destruction in xenograft rejection via direct lysis (perforin), via induction of apoptosis (Fas L) and by mediation of inflammation (IFN-g). Perforin deficient mice (PKO), Fas L deficient mice (gld/gld) and IFN-g deficient mice will be used as donors of CD4+ T cells, which will be transferred into RAG1-/- recipients. RAG 1-/- (T and B cell deficient, not as leaky as SCID mice) recipients will be previously transplanted with rat islets. The hypothesis tested by this series of experiments is that CD4 T cell-mediated rejection of xenogeneic islets requires triggering of inflammation, but it does not require the presence of intact cell-cytotoxicity mediating molecules. Therefore the expected results (supported by preliminary findings) are that PKO CD4 cells will induce rat islet rejection in times similar to those of WT CD4 cells, while IFN-g-deficient CD4 cells will be significantly less efficient in mediating graft rejection. While the pivotal role of CD4+ T cells in xenogeneic islet rejection has been established, it can not be formally ruled out that non T cell-mediated effector mechanisms might contribute (partially or entirely) to the observed phenomena. Specific Aim I b is therefore set forth to explore this working hypothesis. Specific Aim I c will test the hypothesis that CD4+ T cell-mediated rejection of xenogeneic grafts might not require T cell receptor-mediated interaction with the grafted target cells. Specific Aim I d is focused on the analysis of rejection of discordant islet grafts in the pig to mouse model system. In Specific Aim II, the P.I. proposes to investigate the mechanisms that mediate the induction of long term survival of xenogeneic islets grafted in mice treated with a short course of anti-LFA-1 antibodies.

描述：（根据申请人的摘要进行了改编） 拟议的研究是研究T细胞介导的免疫的基础 使用Langerhans的胰岛识别异构细胞移植物 相关模型系统。 在资金期间获得的数据强烈 表明特种胰岛识别的普遍模式是通过 接受者CD4+ T的抗原识别的间接途径 淋巴细胞。 在特定目的I a中，将使用几只免疫缺陷的小鼠来确定 CD4+ T淋巴细胞依赖于大鼠的异种反应性的机制 胰岛。 胰岛异种移植物在裸体和scid中生存的概念 接受者强烈建议，至少在鼠的接受者中，拒绝 这种移植物的取决于T细胞。 此外，获得了证据 在第一个资金期间，这种细胞反应为CD4+ T 依赖细胞的体内。 该提案的第一个目标是分析 分子在异种移植排斥反应中涉及靶细胞破坏的作用 通过直接裂解（穿孔），通过诱导凋亡（FAS L）和 炎症的介导（IFN-G）。 穿孔蛋白缺乏小鼠（PKO），FAS L 缺乏小鼠（GLD/GLD）和IFN-G缺乏小鼠将被用作供体 CD4+ T细胞将转移到Rag1 - / - 受体中。 抹布1 - / - （T和B细胞不足，不像SCID小鼠那样漏水）接受者将是 先前用大鼠胰岛移植。 通过此检验的假设 一系列实验是CD4 T细胞介导的异构化排斥反应 胰岛需要触发炎症，但不需要 完整的细胞毒性介导分子的存在。 因此 预期结果（由初步发现支持）是PKO CD4细胞 将在与WT CD4细胞相似的时间中诱导大鼠胰岛排斥。 而IFN-G缺陷型CD4细胞的效率将显着降低 介导移植物排斥。 虽然CD4+ T细胞在异构胰岛排斥中的关键作用具有 已建立，不能正式排除非T细胞介导的 效应器机制可能（部分或全部）对观察到的 现象。 因此，特定的目标I B是为了探索这种工作的探索 假设。 特定目的I C将检验CD4+ T的假设 细胞介导的异构移植物的排斥可能不需要T细胞 受体介导的与移植靶细胞的相互作用。 具体目的i D专注于分析对不一致的胰岛移植物的排斥 猪到鼠标模型系统。 在特定的目标II中，P.I.求婚 研究介导诱导长期存活的机制 用短期治疗的小鼠移植的异种胰岛 抗LFA-1抗体。