脓毒症大鼠肠损伤时Treg细胞/Th17细胞的变化

Changes in CD4^+ CD25^+ regulatory T cell/T helper cell type 17 during intestinal damage in septic rats

目的评价脓毒症大鼠肠损伤时CD4^+CD25^+调节性T细胞(Treg细胞)/辅助性T细胞17(Th17细胞)的变化。方法清洁级健康成年雄性SD大鼠48只,3月龄,体重200~300 g,采用随机数字表法分为对照组(C组)和脓毒症组(Sep组),每组24只。采用改良盲肠穿孔结扎的方法制备大鼠脓毒症模型。2组术后均以生理盐水进行液体复苏,右颈静脉留置静脉营养管进行肠外营养支持。于术后12、24、48和72 h(T1-4)时每组随机取6只大鼠处死取肠系膜淋巴结和结肠。采用流式细胞术检测肠系膜淋巴结Treg细胞及Th17细胞百分比,ELISA法测定结肠IL-17、IL-23、TGF-β和IL-10的含量。结果与C组比较,Sep组T1时Treg细胞百分比降低,T3,4时Treg细胞百分比和T2-4时Th17细胞百分比升高,T1-4时结肠IL-17和IL-23含量、T3,4时TGF-β含量和T2-4时IL-10含量升高,T2时TGF-β含量降低(P<0.05)。结论脓毒症大鼠肠损伤的机制与Treg细胞和Th17细胞比例失衡有关。

Objective To evaluate the changes in CD4^+CD25^+regulatory T cells(Treg)/helper cell type 17(Th17)during intestinal damage in septic rats.Methods Forty-eight clean-grade Sprague-Dawley rats,aged 3 months,weighing 200-300 g,were divided into control group(group C)and sepsis group(group Sep),with 24 rats in each group.The modified cecal ligation and puncture method was used to establish the model of sepsis in anesthetized rats.Resuscitation was performed with normal saline after operation,and the right jugular vein catheterization was used for treatment of enteral nutrition in two groups.Six rats were sacrificed at 12,24,48 and 72 h after surgery(T1-4),and mesenteric lymph nodes and colon were obtained.The percentage of Treg cells and Thl7 cells in mesenteric lymph nodes was detected by flow cytometry.The contents of interleukin-17(IL-17),IL-23,transforming growth factor beta(TGF-β)and IL-10 in colon tissues were determined by enzyme-linked immunosorbent assay.Results Compared with group C,the percentage of Treg cells was significantly decreased at T1,the percentage of Treg cells at T3,4 and Th17 cells at T2-4 were increased,the contents of IL-17 and IL-23 at T1-4,TGF-βat T3-4 and IL-10 at T2-4 were increased,and TGF-βcontents were decreased at T2 in group Sep(P<0.05).Conclusion The mechanism of intestinal damage is related to Treg and Th17 cell imbalance in septic rats.