免疫球蛋白样转录物3和4在肾移植受者树突状细胞中表达的意义

Expression of ILT3 and ILT4 in dendritic cells of kidney transplantation recipients and its significance

目的 探讨免疫球蛋白样转录物3和4（ILT3和ILT4）在肾移植受者外周血树突状细胞（DC）中的表达情况,并分析其在移植免疫低反应中的作用.方法 选择肾移植后存活5年以上肾功能稳定和慢性排斥反应的受者各10例,分别作为肾功能稳定组和慢性排斥组;另选择10例健康志愿者作为正常对照组.用粒-巨噬细胞集落刺激因子（GM-CSF）和白细胞介素4（IL-4）刺激各组研究对象的外周血单核细胞,诱导培养获得DC.用流式细胞仪测定DC表面分子ILT3和ILT4的表达,并分析各组DC表达的差异;用酶联免疫吸附试验法测定各组血清中ILT3和ILT4的配体HLA-G5的表达水平.结果 ILT3在肾功能稳定组DC中表达水平上调,与正常对照组和慢性排斥组比较,差异有统计学意义（P＜0.05）,而ILT4的表达在各组间比较,差异无统计学意义（P＞0.05）;肾功能稳定组血清中HLA-G5的表达水平较正常对照组和慢性排斥组显著升高,差异有统计学意义（P＜0.05）.结论 长期存活的肾功能稳定受者外周血中高表达ILT3和其配体HLA-G,说明它们可能在外周免疫耐受的诱导和维持中起非常重要的作用.

Objective To study the expression of immunoglobulin-like transcripts 3 （ⅡT3） and ILT4 in peripheral blood dendritic cells （DC） of kidney transplantation recipients and to analyze its significance in immunity hyporesponsiveness of transplantation. Methods Twenty kidney allograft recipients who were survived more than five years were recruited to two groups： renal function stable groups, chronic rejection groups, and 10 healthy volunteers served as a control group. The peripheral blood mononuclear cells （PBMC） were stimulated with granulocyte-macrophage colony stimulating factor （GM-CSF） and interleukin 4 （IL-4） and immature DC were obtained. The expression of ILT3 and ILT4 was detected by using flow cytometry. The level of HLA-G5 in serum was determined by using enzyme linked immunosorbent assay. Results ILT3 expression in renal function stable group was increased and decreased in chronic rejection groups as compared with control group （P〈0.05）,but ILT4 expression had no significant difference among all groups. HLA-G5 in serum was significantly increased in renal function stable group as compared with other groups. Conclusion Expression of ILT3 and HLA-G was increased in the kidney transplantation recipients with stable renal function and long-term survival, suggesting that they may play an important role in inducing and maintaining periphery immune tolerance.