CALCIUM SIGNALING AND KILLING BY CYTOTOXIC T LYMPHOCYTES

描述：本提案的长期目标是了解 细胞毒性T细胞功能中的细胞内钙（[Ca 2 +]i）信号 淋巴细胞（CTL）。 这些免疫系统的关键效应物杀死 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;不适当的杀伤可引起自身免疫性疾病 疾病如狼疮、某些形式的糖尿病和关节炎。 CTL 因此，功能对健康和疾病至关重要， 详细了解CTL的杀伤方式对于理解 病毒性疾病如艾滋病，癌症自身免疫性疾病， 以及防止移植器官的排斥。 治疗策略 可能是通过对CTL功能的详细了解而提出的。 CTL用于杀伤的两种机制之一是穿孔素途径， 包括孔形成肽的胞吐释放和水解 酶包含在专门的CTL裂解颗粒进入区域关闭 与目标形成并置。 颗粒胞吐作用分为两个步骤 过程，包括溶解颗粒的重新定位，然后融合， 并且已知需要由穿过血浆的流入引起的增加的[Ca 2 +]i 膜的 然而，Ca 2+在驱动颗粒中的特定作用 胞吐作用未知。 关键的是，颗粒胞吐作用还没有被研究 利用强大的生理学方法， 了解其他细胞类型的胞吐作用。 具体目标是 建议使用膜片钳记录，电容测量和 数字视频成像技术：1）确定Ca 2+的机制 内流的CTL; 2）调查的想法，Ca 2+通道是本地化， 创建功能性Ca 2+梯度;和3）确定以下各项所起的作用： Ca ~（2+）在颗粒胞吐中。 这些具体目标将建立一个公司 生理基础，了解这一关键的机制， 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.