CALCIUM SIGNALING AND KILLING BY CYTOTOXIC T LYMPHOCYTES

描述：这项建议的长期目标是理解 细胞内钙信号在细胞毒性T细胞功能中的作用 淋巴细胞(CTL)。这些免疫系统的关键效应器会杀死 病毒感染的细胞和癌细胞，并在免疫中发挥主要作用 对移植组织的反应；不适当的杀伤可导致自身免疫 疾病，如狼疮、某些形式的糖尿病和关节炎。CTL 因此，功能与健康和疾病密切相关， 对CTL如何杀死的详细知识对于理解 病毒性疾病的病原学，如艾滋病、癌症、自身免疫性疾病、 以及防止移植器官的排斥反应。治疗策略 可能是由CTL功能的详细知识提示的。 CTL用于杀伤的两种机制之一是穿孔素途径，它 涉及造孔肽和水解物的胞吐释放 特制CTL裂解颗粒中所含的酶进入封闭区域 与目标形成对位。颗粒胞吐分为两步 过程，包括溶解颗粒的重新定位，然后它们的融合， 已知需要通过血浆内流引起的[Ca2+]i增加 薄膜。然而，钙离子在驱动颗粒中的具体作用(S) 胞吐作用尚不清楚。关键的是，颗粒胞吐还没有被研究过。 使用强大的生理学方法，使我们的 了解其他细胞类型的胞吐作用。这样做的具体目的是 建议使用膜片钳记录、电容测量和 数字视频成像技术用于：1)确定钙离子的机制 CTL的流入；2)研究钙通道定位于 创造功能性钙离子梯度；3)确定S所扮演的角色 颗粒胞吐中的钙离子。这些明确的目标将建立一家公司 理解这一危重疾病机制的生理学基础 胞吐事件。

DESCRIPTION: The long term goal of this proposal is to understand the role of intracellular calcium ([Ca2+]i) signals in the function of cytotoxic T lymphocytes (CTLs). These critical effectors of the immune system kill virally infected cells and cancer cells, and play a major role in the immune response to transplanted tissues; inappropriate killing can cause autoimmune diseases such as Lupus, certain forms of diabetes, and arthritis. CTL function is therefore of critical relevance to health and disease, and detailed knowledge of how CTLs kill is of key importance to understanding the etiology of viral diseases such as AIDS, cancer autoimmune disorders, and to preventing rejectio of transplanted organs. Therapeutic strategies may be suggested by detailed knowledge of CTL function. One of the two mechanisms CTLs use to kill is the perforin pathway, which involves the exocytotic release of pore-forming peptides and hydrolytic enzyme contained in specialized CTL lytic granules into an area of close apposition formed with the target. Granule exocytosis is a two step process, involving relocation of lytic granules followed by their fusion, and is known to require increased [Ca2+]i caused by influx across the plasma membrane. However, the specific role(s) of Ca2+ in driving granule exocytosis is unknown. Critically, granule exocytosis has not been studied using the powerful physiological approaches that have advanced our understanding of exocytosis in other cell types. The specific aims of this proposal are to use patch clamp recording, capacitance measurements and digital video imaging techniques to: 1) determine the mechanism of Ca2+ influx in CTLs; 2) investigate the idea that Ca2+ channels are localized to create functional Ca2+ gradients; and 3) determine the role(s) played by Ca2+ in granule exocytosis. These specific aims will establish a firm physiological foundation for understanding the mechanism of this critical exocytotic event.