GPC3抗原表位肽致敏树突状细胞对T淋巴细胞活化的影响

Effect of GPC3 epitope peptide-sensitized dendritic cells on activation of T cells

目的探讨磷脂酰肌醇蛋白聚糖3(GPC3)抗原表位肽致敏的树突状细胞(DC)对T淋巴细胞活化的影响。方法选用基因型人类白细胞抗原A2阳性的剖宫产妇的胎盘端脐带血50 m L,分离培养DC及T细胞,用人工合成的GPC3抗原表位肽(GPC3_(144-152)、GPC3_(298-306))、冻融Hep G2细胞抗原致敏DC (DC-GPC3_(144-152)组、DCGPC3_(298-306)组、DC-HepG2组、DC组),经致敏DC处理的T细胞随机分为DC-GPC3_(144-152)-T组、DC-GPC3_(298-306)-T组、DC-HepG2-T组、DC-T组,以未经活化的T细胞作对照(T细胞组)。用流式细胞术检测DC表型、T细胞分类及表面趋化因子的表达。结果 GPC3_(144-152)、GPC3_(298-306)抗原表位肽和冻融Hep G2细胞抗原三种致敏方式均能诱导DC呈典型成熟DC的形态,表面均高表达CD83、CD80和CD86抗原,且不同致敏方式之间CD8^+T、CD4^+T淋巴细胞比例差异无统计学意义(P均> 0. 05);与T细胞组比较,GPC3_(144-152)-T组和DC-GPC3_(298-306)-T组CD4+T细胞中Th1细胞比例高(P均<0. 05);与DC-T组比较,DC-GPC3_(144-152)-T组、DC-GPC3_(298-306)-T组、DC-HepG2-T组CCR6表达高(P均<0. 05)。结论 GPC3_(144-152)和GPC3_(298-306)表位抗原肽均能够有效致敏DC,并促进与DC共培养的T淋巴细胞活化。

Objective To explore the role of glypican 3(GPC3)epitope peptide-sensitized dendritic cells in activating T lymphocytes.Methods The placental umbilical cord blood(50 mL)of cesarean section with genotype HLA-A2-positive was selected,and dendritic cells(DCs)and T-lymphocytes(T cells)were isolated and cultured.Sensitized DCs were prepared by artificially synthesized GPC3 epitope peptides(GPC3 144-152,GPC3 298-306)and freeze-thawing HepG2 cell antigens(DC-GPC3 144-152 group,DC-GPC3 298-306 group,DC-HepG2 group,DC group).Then the T cells treated by sensitized DCs were successively taken as the DC-GPC3 144-152-T group,DC-GPC3 298-306-T group,DC-HepG2-T group,and DC-T group,and meanwhile,the unactivated T cells were taken as the control group(T cell group),respectively.Flow cytometry was used to detect DC phenotype and T cell classification and surface chemokine expression.Results GPC3 144-152,GPC3 298-306 epitope peptide and freeze-thaw HepG2 cell antigen all induced sensitization of DCs with typical mature DC morphology,and the surface expressed CD83,CD80 and CD86 antigens.There was no significant difference in the proportion of CD8^+T and CD4^+T lymphocytes between different sensitization methods(all P>0.05).Compared with the T cell group,the proportion of Th1 cells in CD4^+T cells increased significantly in the DC-GPC3 144-152-T group and DC-GPC3 298-306-T group(both P<0.05);compared with the DC-T group,the expression of T cell surface chemokine receptor CCR6 increased in the DC-GPC3 144-152-T group,DC-GPC3 298-306-T group,and DC-HepG2-T group(all P<0.05).Conclusion GPC3 144-152 and GPC3 298-306 epitope peptide is capable of sensitizing DC and then activating T lymphocytes.