NKT细胞在小鼠母胎免疫耐受微环境中作用的初步研究

A Preliminary Study of the Role of NKT Cells in Mouse Maternal-Fetal Immune Tolerance Microenvironment

目的探讨自然杀伤T(NKT)细胞在小鼠母胎免疫耐受微环境中的调节作用。方法将48只孕鼠随机分为4组:α-GalCer 1组、α-GalCer 2组、α-GalCer 3组和正常对照组,每组12只。α-GalCer 1、2、3组分别给予α-GalCer 10.3、20.6、41.2mg·L^(-1)腹腔注射,1次·d-1;正常对照组给予0.9%氯化钠注射液0.2mL腹腔注射,1次·d-1。每组实验重复3次。在干预24h后,免疫组织化学SP法检测孕鼠子宫内膜组织中CD3的表达,RT-PCR检测孕鼠外周血单核细胞、子宫蜕膜组织中IL-4mRNA、IFN-γmRNA的表达水平及IFN-γmRNA/IL-4mRNA相对灰度比值。结果在妊娠第3天小鼠干预24h后,与正常对照组比较,20.6mg·L^(-1)的α-GalCer(α-GalCer 2组)明显抑制外周血单核细胞和子宫内膜组织中IFN-γ以及外周血单核细胞中IL-4的mRNA表达,但促进子宫内膜组织中IL-4的mRNA表达(P<0.05)。20.6 mg·L^(-1)的α-GalCer(α-GalCer 2组)促进了外周血单核细胞中IFN-γ/IL-4相对灰度比值的升高,而明显抑制了子宫内膜组织中IFN-γmRNA/IL-4mRNA相对灰度的比值(P<0.05)。在子宫着床期间,由α-GalCer诱导的子宫内膜T细胞数量明显增多。结论围着床期α-GalCer诱导外周NKT细胞活化,可促使外周单核细胞中IFN-γ/IL-4的平衡向Th1漂移,而子宫内膜中活化的NKT细胞使IFN-γ/IL-4的平衡向Th2漂移,有利于子宫内膜形成免疫耐受微环境。

Objective To explore the role of natural killer T(NKT)cells in maternal-fetal immune tolerance microenvironment.Methods Forty-eight pregnant mice were randomly were intraperitoneally injected divided into four groups(n=12 per group).Theα-GalCer1 group,α-GalCer2 group andα-GalCer3 group were intraperitoneally injected with 10.3,20.6 and 41.2 mg·L-1α-GalCer once daily,respectively.The control group was given 0.9%sodium chloride injection(0.2 mL).After treatment for 24 hours,the expression of CD3 protein in endometrium was detected by immunohistochemical staining,and the expression of IL-4 and IFN-γmRNA in peripheral blood mononuclear cells and endometrium and IFN-γmRNA/IL-4 mRNA relative gray ratio was tested by RT-PCR.The experiments were repeated 3 times.Results Compared with control group,treatment with 20.6 mg·L-1α-GalCer inhibited IFN-γmRNA expression in peripheral blood mononuclear cells and endometrium,decreased IL-4 mRNA expression in peripheral blood mononuclear cells,but increased IL-4 mRNA expression in endometrium(P<0.05).Furthermore,20.6 mg·L-1α-GalCer treatment increased the relative optical density ration of IFN-γ/IL-4 in peripheral blood mononuclear cells,but decreased the ration in endometrium(P<0.05).During embryo implantation,α-GalCer significantly increased the number of T cells in endometrium.Conclusion During the peri-implantation period,α-GalCer-induced activation of peripheral NKT cells makes the ratio of IFN-γ/IL-4 drift to Th1 immune response,and the activation of endometrial NKT cells makes the ratio of IFN-γ/IL-4 drift to Th2 immune response.It is advantageous to come into being immune tolerance microenvironment in endometrium.