CVB3诱导Th17/Treg失衡导致小鼠病毒性胰腺炎

Imbalance of Th17/Treg induced by coxsackievirus B3 leads to viral pancreatitis in mice

目的构建CVB3诱导的小鼠胰腺炎模型,观察胰腺组织病理学损伤和浸润Th17/Treg细胞的占比变化。方法BALB/c小鼠腹腔注射CVB3构建急性病毒性胰腺炎模型,通过HE染色观察胰腺病理学改变;q-PCR检测胰腺组织病毒核酸载量和细胞因子(IFN-γ、IL-6和IL-17)mRNA的相对表达量;流式细胞术检测胰腺组织浸润细胞CD45+CD3+T细胞、CD4+和CD8+T细胞、Th17和Treg细胞占比。结果CVB3感染第3天胰腺组织病毒核酸载量为0.96±0.18,且随感染时间点推移而逐渐降低;与3dpi组相比,7dpi组胰腺组织病毒核酸载量有降低趋势(0.96±0.18 vs.0.62±0.14),但无统计学差异。胰腺组织炎症细胞浸润在7dpi后明显增加,损伤评分>2;浸润的Th17细胞(1.05±0.21 vs.22.13±5.79)和Treg细胞(3.11±0.78 vs.8.25±1.30)在CD4+T细胞中占比在感染后7天同时升高(P<0.05),且Th17/Treg比值也明显增高(P<0.01)。与对照组相比,CVB3感染第7天,胰腺组织IFN-γ(1.05±0.23 vs.672.6±47.67)、IL-6(1.00±0.38 vs.68.28±4.57)、IL-17(1.01±0.11 vs.54.15±7.94)的mRNA相对表达量明显升高(P<0.01)。结论CVB3诱导小鼠病毒性胰腺炎,胰腺组织浸润Th17/Treg及其相关细胞因子IL-6和IL-17上调,促进疾病进展。

Objective A mouse model of pancreatitis induced by coxsackievirus B3(CVB3)was established.The pathological change of pancreas and the infiltration of Th17/Treg cells were observed.Methods The BALB/c mice were inoculated intraperitoneally with CVB3 to induce acute viral pancreatitis model.Then the pathological changes of pancreas were observed by HE staining;the viral RNA load and relative expression of cytokines(IFN-γ,IL-6 and IL-17)mRNA were detected by q-PCR;the proportion of infiltrated CD45+CD3+T cells,CD4+and CD8+T cells,Th17 and Treg cells in the pancreas was determined by flow cytometry.Results Three days after CVB3 infection,the viral RNA load in pancreas was the highest(0.96±0.18)and gradually decreased with prolongation of infection.Compared with the 3 dpi group,the viral RNA load in pancreas was decreased(0.96±0.18 vs.0.62±0.14)at 7 dpi,but there was no statistically significant difference.In addition,the infiltration of immune cell in pancreas increased significantly after 7dpi and the pathological score>2.The percent of infiltrated Th17 cells(1.05±0.21 vs.22.13±5.79)and Treg cells(3.11±0.78 vs.8.25±1.30)among CD4+T cells significantly increased after infection(P<0.05),and the Th17/Treg also increased(P<0.01).Compared with the control group,the relative mRNA expression of IFN-γ(1.05±0.23 vs.672.6±47.67),IL-6(1.00±0.38 vs.68.28±4.57),and IL-17(1.01±0.11 vs.54.15±7.94)in pancreas increased at 7 days after CVB3 infection(P<0.01).Conclusions The infiltration of Th17/Treg cells and the expression of related cytokines related cytokines IL-6 and IL-17 mRNA were upregulated in pancreas,which promoted the process of CVB3-induced pancreatitis.