CYTOTOXIC CELLS AND ALLOIMMUNE RESPONSES

描述(改编自调查者摘要)：研究 在本申请中将详细检查颗粒硫醇的作用 蛋白水解酶DPPI在细胞毒T细胞产生中的作用 淋巴细胞(CTL)效应功能与体内同种异体免疫的进化 回应。DPPI已被发现在肿瘤细胞中高水平表达 CTL、自然杀伤细胞、肥大细胞和 髓系细胞，这种酶负责翻译后 表达的颗粒状丝氨酸蛋白酶的加工和激活 免疫效应细胞。最近的研究表明，存在特定的 DPPI抑制剂在同种异体抗原刺激T细胞反应中的作用 不仅可以防止产生具有酶活性的 CTL表达的颗粒丝氨酸蛋白酶颗粒酶家族 多种细胞毒对CD8(+)T细胞生长和分化的影响 效应器功能。拟议的研究将检验这些机制。 因此，抑制DPPI或其他DPPI样蛋白酶(S)会损害世代 不仅依赖于颗粒酶的效应细胞功能，而且似乎 调节其他CD8(+)T细胞反应之前未被归因于 颗粒酶活性。这些具体目标将得到解决：1)确定 DPPI活性或其他DPPI样硫醇蛋白水解酶活性是否发挥作用 CD8(+)T细胞生长和分化中的作用：(A)评估 DPPI特异性反义寡核苷酸对CD8(+)T细胞的影响 生长和增殖；以及(B)类DPPI硫醇的特性 蛋白水解酶可能在CD8(+)T细胞的生长和分化中起作用； (2)检验颗粒酶活性受损导致 抑制CD8(+)T细胞的生长和分化：(A)评估 DPPI中未加工的颗粒酶蛋白的潜在毒性 抑制CTLL-2和CD8(+)T细胞；(B)研究 DPPI处理的颗粒酶对CD8(+)T细胞生长的调节作用 分化；和(C)颗粒酶对细胞因子的影响 APC在MLC中的反应；(3)通过靶向产生DPPI缺陷的T细胞 破坏小鼠DPPI基因；以及(4)评估DPPI在 体内细胞毒效应功能和同种异体免疫反应的产生 在移植物抗宿主病和器官移植排斥反应期间。这些 研究应为CTL效应器的调控提供新的见解 机制及其效应机制在并发症中所起的作用 骨髓和器官移植。

DESCRIPTION (Adapted from the Investigator's abstract): The studies detailed in this application will examine the role of the granule thiol protease, dipeptidyl peptidase I (DPPI) in generation of cytotoxic T lymphocyte (CTL) effector functions and the evolution of in vivo alloimmune responses. DPPI has been found to be expressed at high levels in the specialized effector granules of CTL, natural killer cells, mast cells, and myeloid cells where the enzyme is responsible for post-translational processing and activation of the granule serine proteases expressed in these immune effector cells. Recent studies indicate the presence of specific inhibitors of DPPI during primary alloantigen stimulated T-cell responses not only prevents generation of the enzymatically active forms of the granzyme family of granule serine proteases expressed by CTL but also impairs CD8 (+) T-cell growth and differentiation of multiple cytotoxic effector functions. The proposed studies will examine the mechanisms whereby inhibition of DPPI or other DPPI-like protease(s) impair generation of not only granzyme dependent effector cell function but also appears to modulate other CD8 (+) T-cell responses not previously attributed to granzyme activity. These specific aims will be addressed: 1) Determine whether DPPI activity or other DPPI-like thiol protease activities play roles in CD8 (+) T-cell growth and differentiation by: (a) assessment of the effects of DPPI-specific antisense oligonucleotides on CD8(+) T-cell growth and proliferation; and (b) characterization of DPPI-like thiol proteases that may play a role in CD8(+) T-cell growth and differentiation; (2) Test the hypothesis that impaired granzyme activation leads to diminished CD8(+) T-cell growth and differentiation by: (a) assessment of the potential toxicity of unprocessed granzyme proteins within DPPI inhibited CTLL-2 and CD8 (+) T-cells; (b) investigation of the role of DPPI-processed granzymes in regulating CD8(+) T-cell growth and differentiation; and (c) assessment of the effects of granzymes on cytokine responses by APC during MLC; (3) Generate DPPI deficient T-cells by targeted disruption of the murine DPPI gene; and (4) Assess the role of DPPI in generation of in vivo cytotoxic effector functions and alloimmune responses during graft versus host disease and organ allograft rejection. These studies should provide new insights into the regulation of CTL effector mechanisms and the role that such effector mechanisms play in complications of bone marrow and organ transplantation.