CYTOTOXIC CELLS AND ALLOIMMUNE RESPONSES

描述（改编自研究者摘要）：研究 本申请中详细描述的方法将研究颗粒硫醇 蛋白酶，二肽基肽酶I（DPPI）在细胞毒性T细胞生成中的作用 淋巴细胞（CTL）效应功能和体内同种免疫的演变 应答 已经发现DPPI以高水平表达于 CTL、自然杀伤细胞、肥大细胞的特化效应颗粒，以及 髓样细胞，其中酶负责翻译后 这些细胞中表达的颗粒丝氨酸蛋白酶的加工和活化 免疫效应细胞 最近的研究表明， 在原发性同种异体抗原刺激的T细胞应答期间DPPI的抑制剂 不仅防止了酶促活性形式的产生， 由CTL表达的颗粒丝氨酸蛋白酶的颗粒酶家族，而且 损害CD 8（+）T细胞生长和多种细胞毒性T细胞的分化 效应器功能。 拟议的研究将审查机制， 由此DPPI或其它DPPI样蛋白酶的抑制损害了 不仅颗粒酶依赖的效应细胞功能， 调节其他先前未归因于 颗粒酶活性 这些具体目标将得到解决：1）确定 DPPI活性或其它DPPI样巯基蛋白酶活性是否起作用 CD 8（+）T细胞生长和分化的作用：（a）评估 DPPI特异性反义寡核苷酸对CD 8（+）T细胞的影响 生长和增殖;和（B）DPPI样硫醇的表征 可能在CD 8（+）T细胞生长和分化中起作用的蛋白酶; (2)检验颗粒酶活化受损导致 减少CD 8（+）T细胞的生长和分化：（a）评估 DPPI中未加工颗粒酶蛋白的潜在毒性 抑制的CTLL-2和CD 8（+）T细胞;（B）研究 DPPI处理的颗粒酶调节CD 8（+）T细胞生长和 （c）评估颗粒酶对细胞因子的影响 （3）通过靶向APC产生DPPI缺陷型T细胞; 破坏鼠DPPI基因;和（4）评估DPPI在 体内细胞毒性效应子功能和同种免疫应答的产生 在移植物抗宿主病和器官移植排斥反应期间。 这些 研究将为CTL效应子的调控提供新的见解， 机制以及这种效应机制在并发症中的作用 骨髓移植和器官移植。

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.