Haecker G, Wagner H
Institute of Medical Microbiology and Hygiene, Technical University of Munich, Germany.
Immunology. 1994 Apr;81(4):564-8.
The function and physiological role of gamma delta T cells are still unknown. Concerning the specificity of these cells, a proliferative response towards microbial ligands has been noted, whereas in terms of effector functions in humans a cytolytic activity against a variety of tumour targets is most prominent. Here we show data demonstrating that the cytolytic activity of activated human gamma delta T cells does not reflect the specificity of these cells in primary in vitro stimulation; moreover, we provide evidence that the recognition of target cells by gamma delta T cells can have different qualities. gamma delta T cells proliferate vigorously in primary in vitro reaction upon stimulation with various B-cell tumour lines but not with the T-cell lines Jurkat or Molt-4. However, gamma delta T cells stimulated primarily with phytohaemagglutinin or with cells from B-cell lines gain unrestricted cytolytic activity against a broad set of tumour targets, including Jurkat and Molt-4; the same set of targets is capable of inducing release of serine esterases (SE) from gamma delta T-effector cells. Whereas the cytolytic activity in the 51Cr-assay against the B-cell lines and against Molt-4 depends on the presence of Ca2+ ions in the assay, the lysis of Jurkat cells is only slightly reduced upon removal of Ca2+ from the medium; the SE release, however, is Ca2+ dependent in all cases. Taken together, these data suggest several different ways of target cell recognition by gamma delta T cells leading to either proliferation or triggering of cytolytic activity, and argue against an involvement of the gamma delta T-cell receptor in the cytotoxic activity of gamma delta T cells.
γδ T细胞的功能和生理作用仍然未知。关于这些细胞的特异性，已注意到它们对微生物配体有增殖反应，而在人类中，其效应功能方面，针对多种肿瘤靶标的细胞溶解活性最为突出。在此我们展示的数据表明，活化的人γδ T细胞的细胞溶解活性在体外初次刺激中并不反映这些细胞的特异性；此外，我们提供的证据表明，γδ T细胞对靶细胞的识别可能具有不同性质。γδ T细胞在用各种B细胞肿瘤系刺激时，在体外初次反应中会强烈增殖，但用T细胞系Jurkat或Molt - 4刺激时则不会。然而，主要用植物血凝素或B细胞系的细胞刺激的γδ T细胞对包括Jurkat和Molt - 4在内的多种肿瘤靶标获得了不受限制的细胞溶解活性；同一组靶标能够诱导γδ T效应细胞释放丝氨酸酯酶（SE）。在51Cr测定中，针对B细胞系和Molt - 4的细胞溶解活性取决于测定中Ca2 +离子的存在，而从培养基中去除Ca2 +后，Jurkat细胞的裂解仅略有减少；然而，在所有情况下，SE释放都依赖于Ca2 +。综上所述，这些数据表明γδ T细胞识别靶细胞有几种不同方式，导致增殖或触发细胞溶解活性，并且反对γδ T细胞受体参与γδ T细胞的细胞毒性活性。
