Kabelitz D, Pechhold K, Bender A, Wesselborg S, Wesch D, Friese K, Janssen O
Institut für Immunologie, Universität Heidelberg, Mannheim, Germany.
Immunol Rev. 1991 Apr;120:71-88. doi: 10.1111/j.1600-065x.1991.tb00588.x.
We have concentrated on three functional aspects of human gamma/delta+ T cells. (1) Peripheral blood gamma/delta+ T cells proliferate at a high frequency in response to heat-killed mycobacteria (M.tb.). We present evidence that the primary response of human gamma/delta+ T cells is restricted to those cells bearing a V gamma 9/V delta 2 receptor. (2) T cells expressing the alpha/beta TCR can be activated through the CD2 antigen via an "alternative" pathway. Activation requires the combined signaling of 2 mAb directed against two distinct epitopes of CD2. In striking contrast, cloned gamma/delta+ T cells are activated by a single immobilized anti-CD2 mAb directed against the sheep E-binding epitope of CD2. Stimulation of cloned gamma/delta+ T cells by a single anti-CD2 mAb results in IL-2 production, proliferation, and triggering of cytolytic effector function. (3) Cloned gamma/delta+ T cells are susceptible to programmed cell death (apoptosis) when stimulated simultaneously by anti-CD3/TCR mAb plus exogenous IL-2. The very same clones are activated, however, by the same stimuli in the absence of exogenous IL-2 (but in the presence of LCL feeder cells). This provides the basis for a model where extensive gamma/delta+ T cell proliferation is negatively regulated by antigen plus IL-2.
我们专注于人类γ/δ+ T细胞的三个功能方面。（1）外周血γ/δ+ T细胞对热灭活的分枝杆菌（结核分枝杆菌）有高频增殖反应。我们提供的证据表明，人类γ/δ+ T细胞的主要反应局限于那些带有Vγ9/Vδ2受体的细胞。（2）表达α/βTCR的T细胞可通过“替代”途径经CD2抗原被激活。激活需要两种针对CD2两个不同表位的单克隆抗体的联合信号。与之形成鲜明对比的是，克隆的γ/δ+ T细胞可被一种针对CD2绵羊红细胞结合表位的固定化抗CD2单克隆抗体激活。用单一抗CD2单克隆抗体刺激克隆的γ/δ+ T细胞会导致白细胞介素-2的产生、增殖以及细胞溶解效应功能的触发。（3）当克隆的γ/δ+ T细胞同时被抗CD3/TCR单克隆抗体和外源性白细胞介素-2刺激时，它们易发生程序性细胞死亡（凋亡）。然而，在没有外源性白细胞介素-2（但有LCL饲养细胞）的情况下，相同的刺激会激活这些相同的克隆。这为一个模型提供了基础，即抗原加白细胞介素-2对广泛的γ/δ+ T细胞增殖起负调节作用。
