S-烯丙基巯基半胱氨酸促进CD8+T细胞杀伤功能的机制研究OA北大核心CSTPCD

OBJECTIVE To investigate the effect of SAMC on the killing function of CD8+T cells against nasopharyngeal carcinoma cells and its mechanism.METHODS HK-1 and C666-1 are divided into 0,25,50,and 100 mol/L SAMC group,Western blot was used to detcet PD-L1 expression in tumor cells.CD8+T cells were co-cultured with HK-1 and C666-1 cells in a ratio of 10∶1,and 0,25,50,and 100 μmol/L SAMC were added and detect the killing ability of CD8+T on HK-1 and C666-1.ELISA was used to detect INF-γ and TNF-α concentration.Construct a subcutaneous transplant tumor model of nasopharyngeal HK-1 cells,and divide it into a control group,CD8+T cell group,SAMC group,and SAMC+CD8+T cell group.The tumor volume was measured during treatment in each group of mice.Western blot was used to detect the expression of PD-L1 in the tumor tissue,ELISA was used to detect INF-γ and TNF-α concentration of mouse serum.RESULTS Compared to 0 μmol/L SAMC group,the expression of PD-L1 in 25,50,100μmol/L SAMC group were significantly downregulated(P<0.05).Compared to 0 μmol/L SAMC+CD8+T group,the INF-γ and TNF-α concentration were significantly increased in 25,50,100 μmol/L SAMC+CD8+T group,the lysis rates of HK-1 and C666-1 cells were significantly increased.Compared with the control group,the tumor volume and weight in the CD8+T cell group and SAMC+CD8+T cell group were significantly reduced(P<0.05),the concentration of INF-γ and TNF-α were significantly increased.Compared with the CD8+T cell group,the tumor volume and weight in the SAMC+CD8+T cell group mice significantly decreased(P<0.05),while the serum INF-γ and TNF-α concentration significantly increased(P<0.05),and the expression of PDL-1 in tumor tissue was significantly downregulated(P<0.01).CONCLUSION SAMC can promote the killing function of CD8+T cells by inhibiting the expression of PD-L1 in human nasopharyngeal carcinoma cells.