目的：观察CIK细胞中CD4+T细胞亚群抗肿瘤免疫活性。方法：体外大规模扩增CIK细胞，利用磁珠分离系统富集纯化CIK细胞中的CD4+T细胞亚群。采用胞内染色法分析其中Th1/Th2的比例变化； LDH法和荧光染色法比较4 h和20 h其对raji细胞的杀伤率和raji凋亡。结果：经磁珠分离法富集的CD4+CIK细胞纯度高达96%， 其中Th1/Th2的分布较PBMC有显著的改变：Th1亚群、Th0亚群明显升高，Th2亚群无显著变化。CD4+CIK细胞虽然不能在4 h之内溶解raji细胞，但可在20 h时产生同CD4-CIK细胞同样强大的杀伤活性，荧光染色可见其在4 h之内诱导raji出现早期凋亡的迹象。结论：本研究提示CD4+CIK细胞具有明显的“Th1优势”可以调节宿主免疫细胞活性；同时CD4+CIK细胞可通过诱导肿瘤细胞凋亡实现对肿瘤的抑制和杀伤。

Objective:To observe antitumor immunity of CD4+ T cells subset in CIKs.Methods: After large scale of amplification in vitro, CD4+ T cells subset in CIKs was isolated by magnetic beads separation columns. Distribution of Th1/ Th2 in CD4+ T cells subset in CIKs was analysized by intracellular cytokine staining. Cytotoxicity of purified CD4+ T cells subset in CIKs against raji cells and apoptosis of raji cells after 4 h and 20 h coculture were determined by LDH method and fluorescent staining method.Results: Purity of enriched CD4+ T cells subset in CIKs reached 96%. Comparing with PBMCs, significant increase in Th1 subset and Th0 subset were observed but no statistical differences were found in Th2 subset. Few raji cells were lysed by CD4+ T cells subset in CIKs after 4 h co-incubation. But after 20 h co-incubation, the same effective lysis of raji cells as CD4- T cells subset was obtained in CD4+ T cells subset in CIKs. Fluorescent staining showed that CD4+ T cells subset in CIKs induced apoptosis of raji after 4 h coculture. Conclusion: The present study suggested that CD4+ T cells in CIKs were not only regulatory cells capable of modulating host immune system, but also immune effectors capable of inducing apoptosis in tumor cells.

天津科委自然科学基金资助项目（项目编号023611011）