钙连蛋白(CNX)通过促进MHC Ⅰ表达增强CD8^(+)T细胞对结直肠癌细胞的杀伤作用  

Calnexin(CNX)enhances the killing effect of CD8^(+)T cells on colorectal cancer cells by promoting MHC Ⅰ expression

作　　者：杨婷 郑锦秀 高书华 成敏蓉 薛宇彤 邵莹 李逸涵 杨涛 YANG Ting;ZHENG Jinxiu;GAO Shuhua;CHENG Minrong;XUE Yutong;SHAO Ying;LI Yihan;YANG Tao(Department of Biochemistry and Molecular Biology,School of Basic Medicine,Shanxi Medical University,Taiyuan 030001,China;Department of Pharmacology,School of Basic Medicine,Shanxi Medical University,Taiyuan 030001,China;Department of Pathophysiology,School of Basic Medicine,Shanxi Medical University,Taiyuan 030001,China;The"5+3"Integrated Specialty of Clinical Medicine in the First Clinical Medical College,Shanxi Medical University,Shanxi Medical University,Taiyuan 030001,China;Key Laboratory of the Cell physiology,Shanxi Medical University,Taiyuan 030001,China)

机构地区：[1]山西医科大学基础医学院生物化学与分子生物学教研室,山西太原030001 [2]山西医科大学基础医学院药理学教研室,山西太原030001 [3]山西医科大学基础医学院病理,山西太原030001 [4]山西医科大学第一临床医学院,山西太原030001 [5]山西医科大学细胞生理学教育部重点实验室,山西太原030001

出　　处：《细胞与分子免疫学杂志》2022年第2期97-102,共6页Chinese Journal of Cellular and Molecular Immunology

基　　金：国家自然科学基金(81972325)。

摘　　要：目的分析钙连蛋白(CNX)在结直肠癌(CRC)的异常表达对免疫细胞杀伤作用的影响及分子机制。方法免疫组织化学染色检测组织芯片102对CRC及癌旁组织的CNX的表达;在人HCT-15细胞过表达CNX,在人SW480细胞采用小干扰RNA敲低CNX表达,Western blot法检测主要组织相容性复合体Ⅰ(MHCⅠ)蛋白表达;将过表达CNX的慢病毒感染CT-26小鼠结肠癌细胞,并与脾脏分离的CD8^(+)T细胞共培养,利用细胞毒性试剂盒检测CD8^(+)T细胞对CT-26细胞的杀伤作用,ELISA检测γ干扰素(IFN-γ)与肿瘤坏死因子α(TNF-α)分泌的变化。结果CNX在结直肠癌组织的表达低于癌旁组织;HCT-15细胞过表达CNX后,MHCⅠ的蛋白水平升高:敲低SW480细胞CNX,MHCⅠ表达水平下降。过表达CNX可增强CD8T细胞对CT-26细胞的杀伤能力,且培养液上清中IFN-γ与TNF-α的含量增加。结论CNX可通过促进结直肠癌细胞MHCⅠ表达,增强CD8^(+)T细胞对肿瘤细胞的杀伤作用。Objective To investigate the killing effect and molecular mechanism of aberrant expression of calnexin(CNX) in the colorectal cancer(CRC) on the CD8^(+)T immune cells. Methods Immunohistochemistry was used to detect CNX protein level in 102 pairs of CRC cancer and adjacent non-cancerous tissues. Western blotting was employed to examine the protein expression of MHCⅠ in the HCT-15 cells overexpressed with CNX or in the SW480 cells whose CNX expressions were knockdown by siRNA. Murine CD8^(+)T cells isolated from the spleen were cocultured with CT-26 murine CRC cells infected with lentivirus-mediated CNX overexpression. The killing effect of CD8^(+)T cells on CT-26 cells was determined by cytotoxicity kit. The secretion of interferon γ(IFN-γ) and tumor necrosis factor α(TNF-α) in the culture medium were examined by ELISA. Results The protein level of CNX in colorectal cancer tissues were significantly lower than that in non-cancerous tissues. CNX overexpressed in HCT-15 cells was upregulated and CNX knockdown in SW480 cells downregulated the MHC Ⅰ expression in these cells. Furthermore, the overexpression of CNX could not only enhance the killing effect of CD8;T cells on CT-26 cells, but also promote the secretion of IFN-γ and TNF-α from these cells. Conclusion CNX can enhance the killing potential of CD8^(+)T cells on tumor cells through upregulating the MHC Ⅰ expression in colorectal cancer cells.

关 键 词：钙连蛋白(CNX) MHCⅠ CD8^(+)T细胞 结直肠癌 免疫逃逸 

分 类 号：Q279[生物学—细胞生物学] R392.12[医药卫生—免疫学]