目的：考察两种载肽聚乳酸（(polylatic acid, PLA)免疫微球M1（hAFP158~166）和M2（hAFP218~226）在体外诱导特异性CTL的能力及其对肝癌细胞的杀伤作用。方法： 制备分别荷载表位肽hAFP158~166、、hAFP218~226的PLA免疫微球M1和M2，体外刺激HLA-A2+健康志愿者的外周血单个核细胞（PBMC）作为效应细胞，实验分为3组：对照组、hAFP表达组和hAFP阴性组。采用标准51Cr释放法检测CTL杀伤活性。结果：两种免疫微球在体外均能刺激人PBMC增殖，形成大量可见克隆；两者诱导的效应细胞对hAF＋的荷肽T2细胞、HepG-2和Alexander的杀伤率均达75％以上，均显著高于不表达hAFP的膀胱癌细胞BTT和未荷肽的T2细胞，差异非常显著（P<0.01），而两者杀伤活性之间没有明显差异（P>0.05）。结论：两种载肽聚乳酸免疫微球均能在体外诱导产生特异性CTL，并对表达靶抗原的肝癌细胞有较强杀伤作用。

Objective: To investigate the in vitro efficiency of two kinds of polylatic acid (PLA) immunomicrospheres: M1（hAFP158~166）and M2（hAFP218~226） in specific inducement of CTL and the cytotoxicity of CTL against hepatocellular carcinoma cells. Methods: Pripheral blood monocytes (PBMC) of HLA-A2+ healthy volunteers stimulated in vitro by peptide-loading microspheres were taken as effectors. The experiments were divided into three groups: control group, hAFP+ tumor cells group, and hAFP- tumor cells group. The specific cytolysis of target cells was assessed by 51Cr-release assay. Results: Both M1 and M2 induced proliferation of HLA-A2+ PBMC, forming visible clones. The effector cells induced by M1 and M2 both had an cytolysis rate over 75% for hAFP+ tumor cells, which was significantly higher than that for hAFP- tumor cells (P<0.01). But there was no significant difference in cytolysis rate concerning the two kinds of microspheres (P>0.05). Conclusion: The two kinds of microspheres can both induce specific CTL in vitro, which can effectively kill hAFP+ tumor cells.

国家自然科学基金资助项目（N0.30070855）