红景天苷通过TLR4调控DC提高T细胞对肺癌3LL细胞的杀伤力

Salidroside regulates DC through TLR4 to increase the lethality of T cells to lung cancer 3LL cells

目的:探讨红景天苷(salidroside,SAL)对树突状细胞(dendritic cell,DC)表型及细胞毒性T细胞(cytotoxic T lymphocyte,CTL)抗肿瘤能力的影响。方法:选用Lewis肺癌细胞株3LL、野生型C57BL/6和TLR4-/-C57BL/6小鼠,获取小鼠骨髓来源的DC前体细胞,经过培养分化成未成熟DC,收获第6天的DC,经磁珠分选后获得纯度较高的CD11c+DC。将细胞分成PBS组、SAL组和脂多糖(lipopolysaccharide,LPS)组,培养48 h后用流式细胞术检测SAL体外对DC表面分子、吞噬功能、TLR4通路和对T细胞杀伤能力的影响。结果:与PBS组比较,SAL组DC的表面分子CD80、CD86、MHCⅡ表达水平显著升高(均P<0.05)、吞噬功能显著下降(P<0.05)、TLR4表达水平显著升高(P<0.01);与野生型组比较,TLR4-/-组DC经SAL或LPS处理后,其表面分子CD80、CD86、MHCⅡ的表达水平显著降低(均P<0.05);与PBS组比较,SAL组刺激活化的CTL对肺癌3LL细胞的杀伤效应显著升高(P<0.05)。结论:SAL可以通过调控TLR4诱导DC成熟,从而提高T细胞的杀伤能力。

Objective:To investigate the effect of salidroside(SAL)on the phenotype of dendritic cells(DCs)and the antitumor ability of cytotoxic T lymphocytes(CTL).Methods:Lewis lung cancer cell line 3 LL,wild type(WT)C57 BL/6 mice and TLR4-/-C57 BL/6 mice were chosen for this study.Mice bone marrow derived DC precursor cells were obtained to differentiate into immature DCs,which were harvested on the sixth day of culture.CD11 c+DCs were obtained by magnetic beads screening,and further divided into PBS group,SAL group and lipopolysaccharide(LPS)group.After being cultured for 48 h,the effects of SAL on surface molecules and phagocytosis of DCs as well as the efffect of TLR4 pathway on the killing effect of T cells were detected by Fow cytometry.Results:Compared with PBS group,expressions of DC surface molecules CD80,CD86 and MHCⅡsignificantly increased(all P<0.05),phagocytosis significantly decreased(P<0.05),and TLR4 expression level significantly increased(P<0.01)in SAL group;Compared with WT group,after being treated with SAL or LPS,the expressions of DC surface molecules CD80,CD86 and MHCⅡdecreased significantly in TLR4-/-group(all P<0.05);Compared with PBS group,the activated CTL in SAL group exhibited a significantly elevated killing effect against lung cancer 3 LL cells(P<0.05).Conclusion:SAL can induce DC maturation by regulating TLR4,thus improving the killing ability of T cells.