瘦素对小鼠Treg细胞生成和功能的影响及相关机制研究  

Effects of leptin on Treg cells and the possible mechanism

作　　者：卢龙坤 黄丽 秦阳华[3] 陈岩[3] 韦腾飞 徐忠玉[1] 沈茜[3] Lu Longkun;Huang Li;Qin Yanghua;Chen Yan;Wei Tengfei;Xu Zhongyu;Shen Qian(Department of Clinical Laboratory,Dongnan Hospital,Xiamen University,Zhangzhou 363000,China;Medical Imaging Department,Dongnan Hospital,Xiamen University,Zhangzhou 363000,China;Department of Laboratory Diagnosis,Changhai Hospital,the Second Military Medical University,Shanghai 200433,China)

机构地区：[1]厦门大学附属东南医院检验科,漳州363000 [2]厦门大学附属东南医院医学影像科,漳州363000 [3]第二军医大学附属长海医院实验诊断科,上海200433

出　　处：《中华微生物学和免疫学杂志》2019年第5期340-347,共8页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金(81172883);第九O九医院青年苗圃基金(18Y020,18Y018).

摘　　要：目的探讨瘦素(leptin)对Treg细胞生成和功能的影响及相关机制。方法以瘦素基因敲除的ob/ob小鼠和同系野生小鼠为研究对象;流式细胞术检测Treg细胞比例、比较ob/ob小鼠和野生鼠脾脏Treg细胞功能的差异;免疫磁珠法分选小鼠脾脏CD4+T细胞,在体外培养中观察瘦素对Treg细胞生成和功能的影响;实时荧光定量逆转录聚合酶链反应(qPCR)和Luminex检测技术分别检测与Treg细胞密切相关的细胞因子mRNA相对表达量及培养上清液中蛋白质的表达水平。结果ob/ob鼠外周血、脾脏中Treg细胞的比例均显著高于野生鼠[(11.56±0.72)%vs(5.47±0.81)%、(10.16±0.93)%vs(6.29±0.69)%]。ob/ob小鼠Treg细胞对Teff细胞增殖及分泌TNF-α、IFN-γ的抑制能力显著强于野生鼠[(1.6±0.2)%vs(2.4±0.5)%、(4.3±0.3)%vs(7.2±1.2)%]。在ob/ob小鼠脾脏CD4+T细胞体外培养中添加瘦素可使Treg细胞比例从(12.2±1.8)%下降至(7.6±0.9)%,Treg细胞对Teff(effector T)细胞增殖及分泌TNF-α、IFN-γ的抑制功能亦明显降低;反之,在野生鼠脾脏CD4+T细胞培养中加入抗瘦素抗体,可使Treg细胞比例从(7.8±0.85)%升高至(13.1±1.5)%,Treg细胞的抑制功能明显增强。经体外培养后,ob/ob鼠脾脏CD4+T细胞中Foxp3、IL-10和TGF-βmRNA的相对表达量及上清液中IL-10和TGF-β蛋白表达水平均高于野生鼠。结论瘦素缺乏可使小鼠Treg细胞的生成显著增加,Foxp3、IL-10和TGF-βmRNA的相对表达量及上清中IL-10和TGF-β蛋白表达水平也显著升高。瘦素可能通过下调Foxp3、IL-10和TGF-β的转录,抑制Treg细胞的生成及其功能。Objective To investigate the effects of leptin on Treg cells and the possible mechanism.Methods Leptin-deficient(ob/ob)mice and homologous wild-type mice were used in this study.The percentages of Treg cells in spleen tissues and peripheral blood samples were measured by flow cytometry(FCM).Differences in Treg cell functionality were compared between the two groups.Splenic CD4+T cells,separated from the ob/ob mice and the wild-type mice by magnetic beads,were respectively cultured with leptin and anti-leptin neutralization antibody to evaluate the effects of leptin on Treg cells.Quantitative real-time PCR was performed to analyze the expression of Treg cell-related cytokines at transcriptional level.The levels of IL-10 and TGF-βin the supernatants of CD4+T cell culture were measured with Luminex technology.Results Compared with the wild-type mice,the ob/ob mice showed higher percentages of Treg cells in both peripheral blood samples and spleen tissues[(11.56±0.72)%vs(5.47±0.81)%,(10.16±0.93)%vs(6.29±0.69)%].Treg cells isolated from the ob/ob mice had stronger immunosuppressive effects on the proliferation of effector T(Teff)cells and the secretion of TNF-αand IFN-γthan those from the wild-type mice[TNF-α:(1.6±0.2)%vs(2.4±0.5)%,IFN-γ:(4.3±0.3)%vs(7.2±1.2)%].The percentages of Treg cells were decreased from(12.2±1.8)%to(7.6±0.9)%upon the in vitro treatment of CD4+T cells from the ob/ob mice with leptin and the immunosuppressive effects of Treg cells were also weakened.However,the percentages of Treg cells were increased from(7.8±0.85)%to(13.1±1.5)%upon the in vitro treatment of CD4+T cells from the wild-type mice with anti-leptin antibody and the immunosuppressive effects of Treg cells were improved as well.Moreover,the expression of Foxp3,IL-10 and TGF-βat transcriptional level and the levels of IL-10 and TGF-βin the ob/ob group were higher than those in the wild-type group.Conclusions Leptin deficiency significantly promoted the generation of Treg cells in mice and resulted in an increased expr

关 键 词：瘦素 TREG细胞 FOXP3 白细胞介素10 TGF-Β 

分 类 号：R392[医药卫生—免疫学]