不同肿瘤细胞表面MICA的表达及NK细胞杀伤活性的研究

Analysis of the expression of MICA on tumor cell lines of different histotypes and their sensitivity to NK cytotoxicity

目的观察不同肿瘤细胞表面MICA的表达及其对NK细胞杀伤活性的影响。方法以体外培养的K562(人慢性髓原白血病细胞株)、MCF-7(乳腺癌细胞株)、HR-8348(直肠腺癌细胞株)、CNE-2(人鼻咽癌细胞株)、Hela(人宫颈癌细胞株)为靶细胞,流式细胞仪检测细胞表面MICA的表达,以K562细胞作为对照,应用LDH释放法检测不同效靶比情况下体外培养的NK细胞对靶细胞的杀伤活性。结果K562、MCF-7、HR-8348、CNE-2、Hela细胞表面均表达MICA,体外杀伤试验表明NK细胞对上述肿瘤细胞均有杀伤活性,anti-MICA单抗可部分封闭NK细胞对靶细胞的杀伤活性。结论NK细胞对K562、MCF-7、HR-8348、CNE-2、Hela细胞具有较高的杀伤活性,可作为一种生物治疗手段。

Objective：To investigate the expression of MHC class Ⅰ chain-related gene A（MICA） on different human tumor cells （ K562, MCF-7, HR-8348, CNE-2, HeLa） and their sensitivity to NK cytotoxicity. Methods： Cytotoxicity of NK cells （ isolated from 3 healthy persons） were detected by LDH releasing assay at different effect-to-target cell ratios（E： T）. The expression of MICA was measured by FACS. Results： Different level of MICA was detected on surface of tumor cell lines, anti-MICAmAb could partially inhibit the cytotoxicity of NK cells. Conclusion：NKG2D-MICA interaction can trigger the cytotoxicity of NK cells against tumor,NK cells can be a kind of effector cell for the treatment of some certain tumors.