摘要
目的:比较CD8+CD28-,CD4+CD25+调节性T细胞(Tregulatorycells,Treg)及其亚群表型在大鼠自发免疫耐受形成中的变化,并探讨其在肝移植免疫耐受形成中的作用。方法:(1)建立雄性BrownNorway近交系大鼠(简称BN)到Lewis近交系大鼠(简称LEW)原位肝移植免疫耐受模型(存活>120d),取同周龄LEW大鼠作为对照组,应用梯度离心法分离外周血及脾单个核细胞,应用流式细胞仪检测CD8+CD28-,CD4+CD25+T细胞亚群比例;(2)应用免疫磁珠分离方法,通过间接法阴性分选和直接法阳性分选两步分离纯化CD8+CD28-,CD4+CD25+T细胞,并对其亚型表型进行检测,比较它们在移植耐受前后的差别。结果:(1)耐受组大鼠外周血及脾单个核细胞中CD8+CD28-,CD4+CD25+调节性T细胞的比例同对照组比较:CD8+CD28-T细胞增高,外周血为(30.2±5.8)%比(16.4±6.1)%,脾为(23.7±7.2)%比(13.4±5.5)%,P<0.01;CD4+CD25+T细胞无明显差别,外周血为(9.9±3.5)%比(10.4±4.2)%,脾为(15.1±3.7)%比(14.7±4.6)%,P>0.05。(2)CD8+CD28-,CD4+CD25+T细胞的亚型表型检测,①CD8+CD28-T细胞:耐受组为CD152(CTL4)-,CD11b+,CD25-,CD45RO+;对照组为CD152(CTL4)-,CD11b+,CD25,CD45RO部分表达(76%);②CD4+CD25+T细胞:耐受组为CD152(CTL4)+,CD11b+,CD28+,CD45RO+;对照组为CD152(CTL4)+,CD11b+,CD28+,CD45RO+。结论:CD8+CD28-Treg细胞在耐受组大鼠外周血及脾单个核细胞中的比例明显增高,而CD4+CD25+Treg细胞则无明显改变,提示CD8+CD28-Treg细胞在大鼠肝移植自发耐受的形成中的作用可能更为重要;CD152(CTL4)在两种Treg细胞表达差别可能是引起它们作用及表现不同的重要原因;黏附分子CD11b可能同两种Treg细胞的功能均密切相关;CD8+CD28-Treg细胞包含着不同亚群,而CD45RO表达的增加可能同CD8+CD28-Treg细胞发挥抑制功能密切相关。
Objective： To explore the roles of CD4^＋ CD25^＋ and CD8^＋ CD28^- T regulatory cells in spontaneous tolerance of inbred rats orthotopic liver Transplantation. Methods： The orthotopic liver transplantation models of spontaneous tolerance were established between BN （donor） and LEW （recipient） inbred rats whose survival time was more than 120 days, The expression of CD8^＋ CD28^- T and CD4^＋CD25^＋ T cells in PBMC and spleen were determined by flow cytometry. CD8^＋ CD28^- T and CD4^＋ CD25^＋ T cells were sorted by immunomaguetic beads. The expressions of CD25, CD28, CD152 and CIMSRO on CD8^＋ CD28^- T and CD4^＋ CD25^＋ T regulatory cells were also determined by flow cytometry. Results： Compared with control groups, the proportion of CD8^＋ CD28^- T regulatory cells in spontaneous models was significantly increased in peripheral blood mononuclear cells （PBMC） and spleen [PBMC：（30.2±5.8）% vs（16.4±6.1）%;Spleen（23.7±7.2）% vs（13.4±5.5）% P〈0.01]. CD4^＋ CD25^＋ T regulatory cells had no change ;CD1 l b was expressed on CD8^＋ CD28^- T regulatory cells in both control groups and tolerance groups, and CD25, CD152 （CTL-4）were not expressed on CD8^＋ CD28^- T regulatory cells. The expression of CD 45 RO on CD8^＋ CD28^- T regulatory cells was 76.1% in control groups and more than 90% in tolerance groups; CDllb, CD152（ CTL-4）and CD45RO were expressed on CD4^＋ CD25^＋T regulatory cells in both control groups and tolerance groups. Conclusion ： The roles of CD8^＋ CD28^- T cells were more important than CD4^＋ CD25^＋ T cells in spontaneous tol- erance of rat liver transplantation, the different expressions of CD152 showed the functions of CD8^＋ CD28^- and CD4^＋ CD25^＋ T cells were different. The different expressions of CD45RO suggested CD8^＋ CD28^- T regulatory cells was changed before and after liver transplantation.
出处
《北京大学学报（医学版）》
CAS
CSCD
北大核心
2006年第3期266-270,共5页
Journal of Peking University:Health Sciences
基金
国家自然科学基金(30471629)资助~~
关键词
肝移植
免疫耐受
T淋巴细胞亚群
T淋巴细胞
Liver transplantation
Immune tolerance
T-lymphocyte subsets
T-lymphocyte
