P-glycoprotein Function in Allograft Rejection

描述（由申请人提供）：申请人是一名肾病学家， 对移植免疫学感兴趣，谁有资格并满足所有 指导临床科学家需考虑的必要要求 奖作为他在布里格姆妇女医院肾脏学奖学金的一部分， 医院和波士顿儿童医院，申请人完成了3 多年的实验室研究，在此期间，他获得了实践经验 在细胞和分子免疫学的技术。他的主旨是 研究一直在研究P-糖蛋白的作用， 抗性相关ABC转运蛋白，在同种免疫中， 研究结果发表在免疫学杂志上。申请人 现在正在完成他的肾脏病学奖学金，并将被任命为工作人员 布里格姆妇女医院的成员，并在 哈佛医学院2001年7月1日生效。在这份提案中，申请人 希望建立在他的发现，P-糖蛋白在 体外T细胞活化和APC功能。他发现，P- 糖蛋白阻断抑制同种异体抗原依赖性T细胞，但不抑制丝裂原依赖性T细胞 通过正反馈环抑制IFN-γ和IL-12激活， 从而阻断了原发性同种免疫启动的关键途径 应答这些机制也可能在体内起作用， 因此可能在临床同种异体移植排斥反应中起重要作用。然而，在这方面， P-糖蛋白在T细胞活化和同种异体识别中作用 还没有被探索。此外，分子信号和机制， 在免疫过程中调节T淋巴细胞的P-糖蛋白表达 同种免疫相互作用目前尚不清楚。本提案的目标是 目的：1）确定P-糖蛋白在直接和间接途径中的作用 同种异体识别和同种异体排斥反应在体内的小鼠模型， 研究P-糖蛋白在同种异体移植中的作用。 使用鼠过继转移系统的抗原特异性T细胞活化 其中一小群肽特异性CD 4 + TCR转基因T细胞可以 进行物理跟踪和表型检查;以及3）体外检查 P-糖蛋白在抗原呈递细胞功能中的作用以及在 T细胞和同种异体内皮细胞的定向活化， 对于同种异体移植排斥，基于对一种独特的 同种异体内皮细胞触发T细胞P-糖蛋白的能力 表情申请人在分子生物学和细胞生物学方面的培训 免疫学使他发现了P-糖蛋白在 同种免疫申请人意识到，为了进一步探索他的 最近的发现他需要更多的指导。指导临床科学家 发展奖将为申请人提供关键的机会， 进一步扩大他的免疫学知识， 独立导师和合作导师的实验室提供了理想的 环境，以实现本项目的目标，因为他们的强大 移植免疫学的背景，他们的合作势头， 他们的示范性教学和道德课程。在完成这个项目后， 申请人将熟悉关键的体外和体内 分子和细胞免疫学技术，以检查 独立地和竞争性地发挥相关或新分子靶点的作用 在移植和同种异体移植排斥反应中。

DESCRIPTION (provided by applicant): The applicant is a nephrologist with an interest in transplant immunology, who is eligible for and fulfills all the necessary requirements to be considered for a Mentored Clinical Scientist Award. As part of his nephrology fellowship at the Brigham and Women's Hospital and The Children's Hospital in Boston, the applicant completed 3 years of laboratory-based research during which he gained practical experience in techniques of cellular and molecular immunology. The main thrust of his research has been the study of the role of P-glycoprotein, the multidrug resistance-associated ABC transporter, in alloimmunity, and the principle findings are now being published in the Journal of Immunology. The applicant is now completing his nephrology fellowship and will be appointed as a staff member at the Brigham and Women's Hospital and as an Instructor of Medicine at Harvard Medical School effective July 1, 2001. In this proposal, the applicant wishes to build on his findings that P-glycoprotein serves critical roles in vitro in T cell activation and APC function. He has found that specific P- glycoprotein blockade inhibits alloantigen- but not mitogen-dependent T cell activation by inhibiting IFN-gamma and IL-12 through a positive feedback loop, thus blocking a critical pathway in the initiation of primary alloimmune responses. These mechanisms may also be operative in vivo and P-glycoprotein may therefore play an important role in clinical allograft rejection. However, the in vivo role of P-glycoprotein in T cell activation and allorecognition has not been explored. In addition, the molecular signals and mechanisms that regulate P-glycoprotein expression by T lymphocytes in the course of alloimmune interactions are currently unknown. The goals of this proposal are to: 1) define the role of P-glycoprotein in the direct and indirect pathways of allorecognition and in allograft rejection in vivo in murine models of allotransplantation; 2) investigate the in vivo function of P-glycoprotein in antigen-specific T cell activation using a murine adoptive transfer system where a small population of peptide-specific CD4+ TCR transgenic T cells can be physically tracked and phenotypically examined; and 3) examine in vitro the role of P-glycoprotein in antigen presenting cell function and in the bi- directional activation of T cells and allogeneic endothelium which is critical for allograft rejection, based on the preliminary identification of a unique capacity of allogeneic endothelium to trigger T cellular P-glycoprotein expression. The applicant's training in molecular biology and cellular immunology has allowed him to discover a novel role of P-glycoprotein in alloimmunity. The applicant realizes that in order to further explore his recent findings he needs additional mentoring. The Mentored Clinical Scientist Development Award will provide the critical opportunity for the applicant to further expand his knowledge in immunology necessary for achieving independence. The Mentor's and the Co-Mentor's laboratories provide an ideal environment to accomplish the aims of this project because of their strong background in transplantation immunology, their collaborative momentum and their exemplary didactic and ethical curricula. After completing this project the applicant will be familiar with the critical in vitro and in vivo techniques of molecular and cellular immunology in order to examine independently and competitively the role of related or novel molecular targets in transplantation and allograft rejection.