体外抗原诱导小鼠T细胞对NK细胞功能的抑制及其可能分子机制研究  

Study on the inhibition ability of mice T cell on NK cell in vitro

作　　者：袁军[1] 吴军[1,2] 解志杰[1,2] 王庆红[1,2] 王小娟[1,2] 胡婕[1,2] 

机构地区：[1]贵州省人民医院检验科中心实验室,贵阳550002 [2]第三军医大学烧伤,创伤,复合伤国家重点实验室,重庆430000

出　　处：《中国免疫学杂志》2007年第12期1083-1086,共4页Chinese Journal of Immunology

基　　金：国家自然科学基金面上项目(30200261);重庆市蛋白质组学重点实验室专项经费;贵州省科技攻关项目(黔科合NY字[2006]3055);贵州省优秀科技教育人才省长资金项目(黔省专合字:2005(144)号)资助

摘　　要：目的:为了探讨抗原诱导T细胞抑制对NK细胞功能的抑制及其可能机制。方法:在体外,分别利用抗原、抗原+抗CD80抗体、刀豆蛋白A、抗CD3抗体先行诱导小鼠T细胞,并于诱导后24、48、72、96小时分别引入NK细胞,通过51Cr释放试验动态观察NK细胞的功能状况,激光共聚焦显微镜观察T细胞抑制NK细胞功能的作用模式,同时用RT-PCR方法检测经诱导的T细胞Bc1与Bc2表达情况。结果:①各组在24、48、72小时相点,上清液对NK功能均无显著影响,而到96小时,抗原激活组与抗原+抗CD80抗体诱导组两组上清液对NK细胞的杀伤能力表现出促进作用,与其它各时相点相比有统计学意义(P<0.05),且后者低于前者,二者相比也具统计学意义(P<0.05)。②刀豆蛋白A与抗CD3抗体刺激组T细胞从T细胞接受刺激24小时起至96小时,均表现了抑制NK细胞功能。抗原+抗CD80抗体耐受诱导组与抗原激活组T细胞则是在诱导后48小时方表现出对NK细胞的抑制,与其它两组相比差异具有统计学意义(P<0.05)。③只有同种抗原剌激48小时的细胞培养物可检出Bc1、Bc2。其他时相、其他细胞刺激剂作用下均未能检出Bc1,Bc2的表达。结论:经诱导的T细胞能以直接接触的方式抑制NK细胞功能,但不同诱导剂活化的T细胞引起NK细胞抑制的机制可能不同。小鼠HLA-G的类似物-Bc1与Bc2的表达与抗原信号有关,抗原诱导的小鼠T细胞可能通过表达Bcl与Bc2来抑制NK细胞的功能,从而参与移植耐受的形成,这一结论提示这类非经典MHCI类分子有可能成为移植耐受的检测标志。Objective:To investigate the possible mechanism for inhibited NK cell activity by antigen-encountered T cell.Methods:4 groups were designed in the experiment ①antigen full-stimulating group (antigen+T), ②antigen partial stimulated group (antigen+Anti-CD80+T), ③ConA-stimulating group (ConA+T) and ④Anti-CD3-stimulating group (Anti-CD3+ T). The co-culture of stimulated T cells and NK cells was lasted for 24,8,72 h or 96 h, followed by NK cytotoxicity determination via 51Cr-release test. Meanwhile, RT-PCR was used to detect the expression of Bc1 and Bc2 by T cells.Results:①Supernatants from 24 h, 48 h and 72 h groups showed little effect on NK cell function. While, supernatant harvested from both 96 h cultured of both partial-and full-stimulating groups could promote the cytotoxicity of NK cell. ②After 24 h stimu1ation either by ConA or anti-CD3 antibody, T cells could significantly suppress NK cell cytotoxicity. After 48 h partial-and full-stimulated, T cells showed remarkable inhibitory effects on the function of NK cells. ③The expression of Bc1and Bc2 in T celms could be detected at 48 h after antigen stimulation. However, the expression of Bc1 and Bc2 could not be found at other time points or in other experimental groups.Conclusion:Our data show that partial-and full-stimulating T cells could significantly inhibit NK cell functions through cell contact.The molecular mechanisms might not be the same. The expression of Bc1 and Bc2 by T cells is probably responsible for inhibitory capacity of antigen-drived T cells on NK cell function.

关 键 词：T细胞 NK细胞 器官移植 免疫耐受 

分 类 号：R391[医药卫生—基础医学]