Villalba Martin
Molecular Genetic Institute, Montpellier, France.
Arch Immunol Ther Exp (Warsz). 2004 Jan-Feb;52(1):6-12.
Stimulation of T cells by peptide-presenting antigen-presenting cells (APCs) induces formation of a highly organized complex of receptors, signaling molecules and cytoskeleton components at the immune synapse (IS), the contact site between T cells and APCs. Conjugate formation between T cells and APCs initiates the formation of the IS. After this event, micrometer-scale molecular movements occur in the T cell plasma membrane and the actin cytoskeleton undergoes reorganization. Our current knowledge suggests that formation of the IS is an essential step during T cell activation. This is probably related to the proper localization of certain proteins in specific compartments. One of these proteins is protein kinase Ctheta (PKCtheta), which is absolutely required for T cell activation. During the last years we have made great advances in understanding the function and targets of this kinase, and recent reviews have summarized these findings. In contrast, we do not know the exact mechanism that activates PKCtheta after TCR engagement and the role of PKCtheta activation in the formation of the IS. In this review I analyze the mechanism of the translocation of PKCtheta and discuss the function of PKCtheta in the formation of the IS and, vice versa, the role of the IS in the translocation of PKCtheta.
由呈递肽的抗原呈递细胞（APC）刺激T细胞，会在免疫突触（IS）处诱导形成一个由受体、信号分子和细胞骨架成分组成的高度有序的复合物，免疫突触是T细胞与APC之间的接触位点。T细胞与APC之间形成共轭物会启动免疫突触的形成。此事件发生后，微米级的分子运动在T细胞膜中发生，肌动蛋白细胞骨架也会进行重组。我们目前的认识表明，免疫突触的形成是T细胞激活过程中的一个关键步骤。这可能与某些蛋白质在特定区室中的正确定位有关。其中一种蛋白质是蛋白激酶Cθ（PKCθ），它是T细胞激活绝对必需的。在过去几年里，我们在理解这种激酶的功能和靶点方面取得了很大进展，最近的综述总结了这些发现。相比之下，我们尚不清楚T细胞受体（TCR）结合后激活PKCθ的确切机制以及PKCθ激活在免疫突触形成中的作用。在这篇综述中，我分析了PKCθ转位的机制，并讨论了PKCθ在免疫突触形成中的功能，反之亦然，免疫突触在PKCθ转位中的作用。
