Wei Y, Zhao X, Kariya Y, Fukata H, Teshigawara K, Uchida A
Department of Late Effect Studies, Radiation Biology Center, Kyoto University, Yoshida-Konoecho, Sakyo-ku, Japan.
Cancer Res. 1996 Mar 1;56(5):1104-10.
Autologous tumor killing (ATK) has been implicated as an important prognostic factor in cancer patients since the ability of blood lymphocytes to kill freshly isolated autologous tumor cells was strongly associated with good prognosis of the patients. The present study was designed to induce or enhance ATK sensitivity of fresh human tumor cells by heat stress. Brief exposure of fresh human tumor cells to elevated temperature increased their susceptibility to lysis by autologous blood lymphocytes in a short-term (51)Cr release assay. In addition, the heat-elevated ATK sensitivity was confirmed by clonogenic assays. An increase in ATK was observed with unstimulated lymphocytes in 42% of the cases and OK432 (streptococcal preparation)-activated lymphocytes in 80% of the cases. Stimulation of blood lymphocytes with autologous, heat-stressed tumor cells and OK432 resulted in an increase in number of gamma delta T cells, which was associated with elevated ATK activity against the stressed tumor cells. At the clonal level, three gamma delta T-cell clones (V gamma 9/V delta 2+) proliferated in response to autologous, heat stressed tumor cells and/or OK432 and exhibited elevated cytotoxicity against the tumor cells. Western blot analysis revealed an increased expression of heat shock protein (HSP) 70 in heat- treated tumor cells. Some of them expressed HSP70 on their surfaces. The elevated cytoxicity against heat-stressed tumor cells was inhibited by treatment of targets with anti-HSP70 monoclonal antibody (mAb) or of effector cells with anti-V delta2 mAb. Reactivity of gamma delta T cells to autologous, heat- stressed tumor cells was also inhibited by anti-HSP70 mAb. These results indicate that exposure to heat of tumor cells induces ATK susceptibility, especially to OK432-activated effector cells, and suggest that gamma delta T cells may be involved in ATK against stressed tumor cells through recognition of HSP70 on the target cells.
自体肿瘤杀伤（ATK）被认为是癌症患者的一个重要预后因素，因为血液淋巴细胞杀伤新鲜分离的自体肿瘤细胞的能力与患者的良好预后密切相关。本研究旨在通过热应激诱导或增强新鲜人肿瘤细胞的ATK敏感性。将新鲜人肿瘤细胞短暂暴露于高温下，在短期（51）铬释放试验中增加了它们对自体血液淋巴细胞裂解的敏感性。此外，通过克隆形成试验证实了热增强的ATK敏感性。在42%的病例中，未刺激的淋巴细胞观察到ATK增加，在80%的病例中，OK432（链球菌制剂）激活的淋巴细胞观察到ATK增加。用自体热应激肿瘤细胞和OK432刺激血液淋巴细胞导致γδT细胞数量增加，这与针对应激肿瘤细胞的ATK活性升高有关。在克隆水平上，三个γδT细胞克隆（Vγ9/Vδ2+）对自体热应激肿瘤细胞和/或OK432有反应并增殖，对肿瘤细胞表现出增强的细胞毒性。蛋白质印迹分析显示热处理肿瘤细胞中热休克蛋白（HSP）70的表达增加。其中一些细胞在其表面表达HSP70。用抗HSP70单克隆抗体（mAb）处理靶细胞或用抗Vδ2 mAb处理效应细胞可抑制对热应激肿瘤细胞的增强细胞毒性。抗HSP70 mAb也抑制γδT细胞对自体热应激肿瘤细胞的反应性。这些结果表明，肿瘤细胞受热诱导ATK敏感性，特别是对OK432激活的效应细胞的敏感性，并表明γδT细胞可能通过识别靶细胞上的HSP70参与针对应激肿瘤细胞的ATK。
