CD4~+CD25~+调节性T细胞对哮喘大鼠免疫功能影响

目的:观察CD4+CD25+调节性T细胞(CD4+CD25+Treg)对CD4+CD25-T细胞增殖和Th1/Th2细胞因子分泌的影响,探讨其在哮喘气道炎症中的作用机制。方法:将哮喘大鼠CD4+CD25-T细胞分别与卵白蛋白(OVA)免疫耐受大鼠CD4+CD25+Treg细胞和哮喘大鼠CD4+CD25+Treg细胞联合培养,3H胸腺嘧啶核苷(3H-TdR)掺入法测量细胞增殖情况,ELISA检测细胞IL-4、IL-5和IFN-γ含量。结果:OVA耐受大鼠CD4+CD25+Treg细胞能抑制CD4+CD25-T细胞增殖和Th2细胞因子分泌(P<0.05);哮喘大鼠CD4+CD25+Treg细胞可明显抑制IFN-γ的分泌(P<0.05)。结论:OVA免疫耐受大鼠CD4+CD25+Treg细胞可能通过抑制哮喘大鼠CD4+CD25-T细胞增殖和影响Th1/Th2平衡发挥作用,哮喘大鼠CD4+CD25+Treg细胞存在功能异常,可能与哮喘的发病有关。

Effect of CD4+CD25+Regulatory T Cells on the Immunologic Function in Rats with Asthma

Objective To investigate the effects of CD4＋CD25＋ regulatory T cells（CD4^＋CD25^＋ Treg） on the proliferation of CD4^＋CD25^-T cells and the secretion of Th1/Th2 cytokines,and to explore its role in the mechanism of airway inflammation.Methods CD4^＋CD25^-T cells of asthmatic rats were co-cultured with CD4^＋CD25^＋ Treg of OVA-immune tolerant rats or CD4^＋CD25^＋ Treg of asthmatic rats,respectively.The proliferation of CD4^＋CD25^-T cells was detected with 3H-thymidine ribotide（3H-TdR） incorporation,the contents of IL-4,IL-5 and IFN-γ were determined with ELISA.Results The proliferation of CD4^＋CD25^-T cells and secretion of Th2 cytokines were significantly inhibited with CD4^＋CD25^＋ Treg of OVA-immune tolerant rats（P0.05）,and the secretion of IFN-γ was significantly inhibited with CD4^＋CD25^＋ Treg of asthmatic rats（P0.05）.Conclusion CD4^＋CD25^＋ Treg of OVA-immune tolerant rats could alleviate the airway inflammation of asthmatic rats through inhibiting the proliferation of CD4^＋CD25^-T cells and secretion of Th1/Th2 cytokines.The abnormal function of CD4^＋CD25^＋ Treg in asthmatic rats may relate with the pathogenesis of asthma.