Thibault C, Nelson H, Chapoval A I
Division of Colon and Rectal Surgery, Mayo Clinic, Rochester, MN, USA.
Int J Cancer. 1996 Jul 17;67(2):232-7. doi: 10.1002/(SICI)1097-0215(19960717)67:2<232::AID-IJC14>3.0.CO;2-D.
In vitro-activated T lymphocytes can be retargeted with anti-CD3 x anti-tumor bispecific antibodies (BsAb) to kill tumor cells in vitro and in vivo. The purpose of the present study was to examine the systemic and intra-tumor effects of in vivo T-cell activation with BsAb, staphylococcal enterotoxin B (SEB), and beta-glucan in combination with BsAb as a retargeting agent. CL-62 melanoma cells were injected subcutaneously into C3H/ HeN mice. Mice were subsequently treated with BsAb alone or with SEB or beta-glucan plus BsAb. Fresh splenocytes, lymph-node cells and tumor-infiltrating lymphocytes (TIL) were tested for their proliferative response using incorporation of 3H-thymidine, and for their ability to lyse CL-62 cells in the presence or absence of BsAb in 4-hr 51Chromium release assays. Toxicity of treatments was assessed in a D-galactosamine model. BsAb, alone or combined with beta-glucan, had essentially no effect on systemic T-cell cytotoxicity, and essentially no effect on systemic proliferation, unless exogenous IL-2 was provided. At the tumor site, BsAb alone, BsAb plus beta-glucan, and SEB plus BsAb all significantly increased BsAb-mediated TIL cytotoxicity. In contrast to the TIL-limited effects of BsAb and of BsAb plus beta-glucan, SEB plus BsAb markedly increased both systemic and intra-tumor T-lymphocyte activation. Toxicity correlated with measures of systemic activation, with limited effects from BsAb alone and from beta-glucan plus BsAb, and with marked lethality from SEB plus BsAb. Overall, these results suggest moderate intra-tumor activation of TIL, but no measurable systemic activation after in vivo treatment with BsAb or beta-glucan plus BsAb. SEB plus BsAb results in complete T-cell activation in both systemic and intra-tumor compartments, but at the expense of increased systemic toxicity. In conclusion, TIL can be activated in situ with different combinations of in vivo activants. In vivo-activated TIL can be retargeted with bispecific antibodies to lyse tumor cells, and may be an alternative to ex vivo T-cell activation and adoptive transfer therapy.
体外活化的T淋巴细胞可以用抗CD3×抗肿瘤双特异性抗体（BsAb）重新靶向，以在体外和体内杀死肿瘤细胞。本研究的目的是研究BsAb、葡萄球菌肠毒素B（SEB）和β-葡聚糖联合BsAb作为重新靶向剂在体内激活T细胞的全身和肿瘤内效应。将CL-62黑色素瘤细胞皮下注射到C3H/HeN小鼠体内。随后，小鼠单独用BsAb或与SEB或β-葡聚糖加BsAb联合治疗。使用3H-胸腺嘧啶掺入法检测新鲜脾细胞、淋巴结细胞和肿瘤浸润淋巴细胞（TIL）的增殖反应，并在4小时51铬释放试验中检测它们在有无BsAb存在下裂解CL-62细胞的能力。在D-半乳糖胺模型中评估治疗的毒性。单独的BsAb或与β-葡聚糖联合使用，对全身T细胞细胞毒性基本没有影响，对全身增殖也基本没有影响，除非提供外源性白细胞介素-2。在肿瘤部位，单独的BsAb、BsAb加β-葡聚糖和SEB加BsAb均显著增加BsAb介导的TIL细胞毒性。与BsAb和BsAb加β-葡聚糖对TIL的有限作用相反，SEB加BsAb显著增加了全身和肿瘤内T淋巴细胞的激活。毒性与全身激活的指标相关，单独的BsAb和β-葡聚糖加BsAb的作用有限，而SEB加BsAb则具有明显的致死性。总体而言，这些结果表明，TIL在肿瘤内有适度激活，但在用BsAb或β-葡聚糖加BsAb进行体内治疗后，没有可测量的全身激活。SEB加BsAb可导致全身和肿瘤内T细胞完全激活，但代价是全身毒性增加。总之，TIL可以用不同的体内激活剂组合在原位激活。体内激活的TIL可以用双特异性抗体重新靶向以裂解肿瘤细胞，并且可能是体外T细胞激活和过继性转移治疗的替代方法。
