肿瘤组织中Tim-3表达的特征及其在肿瘤免疫耐受中的作用  

Expression of Tim-3 in tumor tissue and its role in the induction of tumor immune tolerance

作　　者：朱汉钢[1] 冯作化[1] 耿辉[1] 张桂梅[1] 

机构地区：[1]华中科技大学同济医学院生物化学与分子生物学系,湖北武汉430030

出　　处：《细胞与分子免疫学杂志》2005年第4期403-407,共5页Chinese Journal of Cellular and Molecular Immunology

基　　金：国家自然科学基金资助项目(No.30471587)

摘　　要：目的:研究小鼠肿瘤发生早期两型含T细胞免疫球蛋白及黏蛋白结构域的分子3(Tim3)的表达特点,以及与免疫调节相关基因表达的时空关系,并探讨其在诱导肿瘤免疫耐受中的作用。方法:建立小鼠实体瘤模型,采用RTPCR法检测肿瘤组织中可溶型Tim3(sTim3)和膜型Tim3(flTim3),以及叉头盒P3(forkheadboxP3,Foxp3)、细胞毒性T淋巴细胞抗原4(CTLA4)、糖皮质激素诱导的肿瘤坏死因子受体家族相关受体(GITR)、TGFβ、IL10和IFNγ等在不同时相的表达及相应时相肿瘤的生长情况。结果:在早期的肿瘤组织中,sTim3的表达先于flTim3,其后flTim3大量表达,而sTim3的表达则下调直至消失。Foxp3和GITR随flTim3同时表达并逐步上调。CTLA4的表达先于flTim3,并随着时间的推移表达上调。flTim3同Foxp3的表达具有空间位置的一致性。flTim3、Foxp3和CTLA4的表达水平同肿瘤的生长呈正相关。结论:随着肿瘤不断的生长,肿瘤局部的免疫应答逐渐趋向于负调节。flTim3在诱导肿瘤免疫耐受的过程中发挥着重要作用,而sTim3可能起着不同的作用。AIM: To explore the role of T cell immunoglobulin- and mucin- domain containing molecule-3 (Tim-3) in the induction of tumor immune tolerance by investigating the expression of two types of Tim-3 at the early stage of tumorigenesis and the temporal-spatial relationship between the expression of Tim-3 and other immuno-inhibitory genes in tumor. METHODS: By using semi-quantitative RT-PCR method, we investigated the expression of Tim-3, forkhead box P3 (Foxp3), cytotoxic T lymphocyte antigen 4 (CTLA-4), glucocorticoid-induced tumor necrosis factor receptor family-related receptor (GITR), TGF-β, IL-10 and IFN-γ at different time in tumor of tumor-bearing mice. Meanwhile, the growth of tumor was determined. RESULTS: At the early stage of tumorigenesis, sTim-3 was expressed before flTim-3 in tumor. When flTim-3 was expressed, the expression of sTim-3 was down-regulated. The expression of Foxp3, and GITR was simultaneous with that of flTim-3 and was up-regulated gradually with tumor growth. The expression of CTLA-4 was earlier than that of flTim-3 and also up-regulated gradually. The expression of flTim-3 and Foxp3 was also consistent with each other in tissue distribution. The growth of tumor was postively correlated with the expression of flTim-3, Foxp3, and CTLA-4 and negatively with the expression of sTim-3. CONCLUSION: Along with the growth of tumor, immune tolerance was gradually established in tumor. flTim-3 but not sTim-3 may induce of tumor immunological tolerance.

关 键 词：sTim-3 flTim-3 肿瘤 免疫耐受 

分 类 号：R392.12[医药卫生—免疫学]