Skeen M J, Ziegler H K
Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30322.
J Exp Med. 1993 Sep 1;178(3):985-96. doi: 10.1084/jem.178.3.985.
Peritoneal gamma/delta T cells from Listeria-immune mice show an enhanced potential to expand when restimulated with antigens or mitogens in vitro (see companion paper [Skeen, M. J., and H. K. Ziegler. 1993. J. Exp. Med. 178:971]). When cocultured with peritoneal alpha/beta T cells, the gamma/delta T cell population expanded preferentially even when the in vitro stimulus was specific for the alpha/beta T cell population. Purified gamma/delta T cells did not respond to alpha/beta T cell-specific stimuli. If isolated T cell subsets were recombined in cell mixing experiments, the resulting proliferative response was greater than additive. Irradiated alpha/beta T cells could enhance the proliferation of responding gamma/delta T cells, but the effect was unidirectional; i.e., irradiated gamma/delta T cells did not stimulate responding gamma/delta T cells. This effect appeared to be cytokine mediated and did not require cell-cell contact. Both recombinant interleukin 2 (rIL-2) and rIL-7 could support the expansion of the gamma/delta T cells, while rIL-7 was only minimally stimulatory for the alpha/beta T cells. The magnitude of the response by gamma/delta T cells to rIL-7 exceeded the response to other in vitro stimuli, including immobilized anti-T cell receptor monoclonal antibody, and was 50-100-fold greater than the alpha/beta T cell response to IL-7. This unique sensitivity of gamma/delta T cells to IL-7 was strongly enhanced by the presence of accessory cells. These cells could be replaced by rIL-1, establishing a synergy for IL-1 and IL-7 as factors that could uniquely stimulate this gamma/delta T cell population. Isolated peritoneal gamma/delta T cells from Listeria-immune mice react to heat-killed Listeria preparations in the presence of macrophages accessory cells in a non-H-2-restricted manner. Considered collectively, these results suggest a potential mechanism by which gamma/delta T cells can predominate in epithelial tissues and at sites of infection.
来自对李斯特菌免疫小鼠的腹腔γ/δ T细胞在体外被抗原或丝裂原再次刺激时显示出更强的扩增潜力（见配套论文[Skeen, M. J., and H. K. Ziegler. 1993. J. Exp. Med. 178:971]）。当与腹腔α/β T细胞共培养时，即使体外刺激是针对α/β T细胞群体的，γ/δ T细胞群体也会优先扩增。纯化的γ/δ T细胞对α/β T细胞特异性刺激无反应。如果在细胞混合实验中重组分离的T细胞亚群，产生的增殖反应大于相加效应。经照射的α/β T细胞可增强反应性γ/δ T细胞的增殖，但这种效应是单向的；即经照射的γ/δ T细胞不会刺激反应性γ/δ T细胞。这种效应似乎是由细胞因子介导的，不需要细胞间接触。重组白细胞介素2（rIL-2）和rIL-7都能支持γ/δ T细胞的扩增，而rIL-7对α/β T细胞的刺激作用最小。γ/δ T细胞对rIL-7的反应强度超过对其他体外刺激的反应，包括固定化抗T细胞受体单克隆抗体，并且比α/β T细胞对IL-7的反应大50 - 100倍。辅助细胞的存在强烈增强了γ/δ T细胞对IL-7的这种独特敏感性。这些细胞可以被rIL-1替代，从而确立了IL-1和IL-7作为能够独特刺激该γ/δ T细胞群体的因子之间的协同作用。来自对李斯特菌免疫小鼠的分离腹腔γ/δ T细胞在巨噬细胞辅助细胞存在的情况下以非H-2限制的方式对热灭活的李斯特菌制剂产生反应。综合考虑，这些结果提示了一种γ/δ T细胞在上皮组织和感染部位能够占优势的潜在机制。
