费先艳张　新于成功，2▲

南京大学医学院附属鼓楼医院消化科1(210008)　南京医科大学鼓楼临床学院2



淋巴细胞功能相关抗原-1调节Treg细胞对炎症性肠病的疗效观察*

费先艳1#张新1于成功1，2▲

南京大学医学院附属鼓楼医院消化科1(210008)南京医科大学鼓楼临床学院2

背景：Treg细胞对炎症性肠病(IBD)具有免疫保护作用，淋巴细胞功能相关抗原-1(LFA-1)参与了IBD时Treg 细胞的分化和迁移。目的：探讨LFA-1调节Treg细胞对IBD疗效的影响。方法：将LFA-1基因缺失小鼠和相同遗传背景野生型小鼠各20只分别随机分为炎症组和治疗组。小鼠饮用2.5% DSS溶液诱导结肠炎模型，治疗组小鼠通过尾静脉回输体外诱导的Treg细胞。观察小鼠一般情况和结肠组织学表现，流式细胞术检测外周血、脾脏、肠系膜淋巴结中Treg细胞比例，ELISA法检测血清TGF-β1、IL-10、IL-17A、IFN-γ水平，实时PCR检测结肠组织TGF-β1、IL-10 mRNA表达。结果：LFA-1缺失治疗组结肠组织学评分与野生型治疗组无明显差异。LFA-1缺失治疗组肠系膜淋巴结Treg细胞比例显著高于相应炎症组(P<0.05)；LFA-1缺失治疗组外周血、脾脏、肠系膜淋巴结Treg细胞比例显著低于野生型治疗组(P<0.05)。与相应炎症组相比，野生型和LFA-1缺失治疗组血清TGF-β1、IL-10以及结肠组织TGF-β1 mRNA表达显著升高(P<0.05)，IL-17A、IFN-γ以及IL-10 mRNA表达显著降低(P<0.05)。野生型治疗组血清TGF-β1、IL-10以及TGF-β1、IL-10 mRNA表达显著高于LFA-1缺失治疗组(P<0.05)，IL-17A、IFN-γ显著降低(P<0.05)。结论：LFA-1参与了Treg细胞功能的调控，能促进Treg细胞分泌抗炎因子TGF-β1、IL-10等。Treg细胞治疗LFA-1缺失结肠炎小鼠的疗效低于野生型小鼠，可能与Treg细胞功能和细胞因子的分泌受到抑制相关。

淋巴细胞功能相关抗原1；T淋巴细胞，调节性；炎症性肠病；细胞因子类

Correspondence to:YU Chenggong,Email:chenggong_yu@nju.edu.cn.

Background:Treg cells play an immunoprotective role in inflammatory bowel disease (IBD).Lymphocyte function-associated antigen-1 (LFA-1) is involved in the differentiation and migration of Treg cells in IBD.Aims:To investigate the efficacy of LFA-1 on IBD by regulating Treg cells.Methods:Twenty LFA-1 gene knockout (LFA-1-/-) mice and 20 wild type mice with same genetic background were randomly divided into colitis group and treatment group,respectively.Colitis model was induced by drinking 2.5% DSS solution.Mice in treatment group were injected with Treg cells induced in vitro through the tail vein.General condition and colon histology were examined.Percentages of Treg cells in peripheral blood,spleen and mesenteric lymph node were detected by flow cytometry.Serum levels of TGF-β1,IL-10,IL-17A and IFN-γ were measured by ELISA.mRNA expressions of TGF-β1 and IL-10 in colon tissue were detected by real time PCR.Results:No significant difference in colon histological score was found between LFA-1-/-treatment group and wild type treatment group.Percentage of Treg cells in mesenteric lymph node in LFA-1-/-treatment group was significantly higher than that in LFA-1-/-colitis group (P<0.05).Percentages of Treg cells in peripheral blood,spleen and mesenteric lymph node in LFA-1-/-treatment group were significantly lower than those in wild type treatment group (P<0.05).Compared with corresponding colitis group,serum levels of TGF-β1,IL-10 and colon tissue TGF-β1 mRNA expression in wild type treatment group and LFA-1-/-treatment group were significantly increased (P<0.05),levels of IL-17A,IFN-γ and expression of IL-10 mRNA were significantly decreased (P<0.05).Serum levels of TGF-β1,IL-10 and expressions of TGF-β1,IL-10 mRNA in wild type treatment group were significantly increased when compared with LFA-1-/-treatment group (P<0.05),levels of IL-17A and IFN-γ were significantly decreased (P<0.05).Conclusions:LFA-1 is involved in the regulation of Treg cells function,and can induce the secretion of anti-inflammatory cytokines TGF-β1 and IL-10.The efficacy of Treg cells in LFA-1-/-colitis mice is inferior to that in wild-type colitis mice,which may be related to the inhibiting of LFA-1 function and secretion of cytokines.

炎症性肠病(IBD)包括溃疡性结肠炎(UC)和克罗恩病(CD)，主要表现为慢性非特异性肠道炎症，其病因和发病机制不明。目前认为环境、微生物、免疫、遗传等因素参与了IBD的发病过程。异常的免疫应答能引起肠道对微生物免疫耐受的失调，进而导致肠道组织损伤、炎症的发生发展[1]。CD4+CD25+Foxp3+调节性T细胞(Treg细胞)在维持肠道免疫耐受和控制肠道炎症中起有重要作用，动物模型和临床研究均已证实Treg细胞的缺失或功能异常与IBD病因学相关[2]。……