外源性细胞因子对柯萨奇病毒性心肌炎小鼠脾Th17细胞的影响

目的:观察转化生长因子(TGF)-β、白细胞介素(IL)-6和IL-23对柯萨奇病毒性心肌炎(VMC)小鼠脾中Th17细胞分化增殖的影响。方法:以6周龄雄性Balb/c小鼠腹腔注射柯萨奇病毒液建立VMC模型,1周后磁珠分离脾脏CD4+T淋巴细胞,分成对照组、TGF-β+IL-6组和TGF-β+IL-6+IL-23组进行体外培养。5d后应用流式细胞术测定刺激后Th17细胞的百分比;逆转录-聚合酶链式反应测定细胞中IL-17mRNA的表达;ELISA测定细胞培养上清液IL-17的水平。结果:与对照组比较,TGF-β+IL-6组Th17细胞数稍增加(1.64±0.43)%∶(1.96±0.35)%],IL-17mRNA表达水平及细胞培养上清液IL-17浓度稍增加,但差异无统计学意义(P>0.05)。而TGF-β+IL-6+IL-23组Th17细胞数显著增加(4.08±0.77)%、IL-17mRNA表达水平及细胞培养上清液IL-17浓度均明显高于前2组,差异有统计学意义(P<0.05)。结论:外源性TGF-β联合IL-6对VMC小鼠脾中已分化的Th17细胞无增殖作用,而添加外源性IL-23则能显著增加Th17细胞数及其效应分子IL-17的表达。

Effects of exogenous cytokine on Th17 cells in murin viral myocarditis induced by coxsackie virus B3

Objective:To observe the effect of recombinant TGF-β,IL-6 and IL-23 on Th17 cells differentiation and proliferation in murin model of coxsackie virus B3(CVB3)-induced viral myocarditis(VMC). Method:VMC was induced in male Balb/c mice by CVB3 peritoneal injection.Murin splenocytes were prepared one week later,and CD4+T cells were isolated by immunomagnetic beads.The CD4+T cells were cultured and divided into groups as follows: ①control group;②TGF-β+IL-6 group;③TGF-β+IL-6+IL-23 group in vitro.Five days later,flow cytometric analysis was used to evaluate the percentage of Th17 subsets in CD4+T cell.The expression of IL-17 mRNA was analyzed by RT-PCR.And the concentration of IL-17 in the culture supernatant was assayed by ELISA. Result:Compared with the control group,the quantity of Th17 cells increased slightly(1.64±0.43]% vs 1.96±0.35]% respectively).and the expression of IL-17 mRNA and the concentration of IL-17 in the culture supernatant were also higher in TGF-β+IL-6 group,but the difference wasn’t significant(P>0.05).However,in TGF-β+IL-6+IL-23 group,the quantity of Th17 cells increased obviously(4.08±0.77)%,and the expression of IL-17 mRNA and the concentration of IL-17 in the culture supernatant augmented apparently than the other two groups with statistical significance(P<0.05). Conclusion:Exogenous TGF-β in combination of IL-6 stimulation have no effect on the proliferation of spleen differentiated Th17 cells in the VMC mice.But addition of exogenous IL-23 increases the population of Th17 cells and up-regulates the level of IL-17 significantly.