人类白细胞抗原G在肾移植受者外周血的表达探讨

目的 探讨人类白细胞抗原(HLA)G的膜型HLA-G(mHLA-G)、胞内HLA-G(iHLA-G)和可溶型HLA-G(sHLA-G)在肾移植受者外周血的表达及其与术后临床相关性.方法 研究对象为2000年2月至2006年6月解放军第三零九医院全军器官移植中心行肾移植的175例受者,根据4周内是否发生排斥反应分为急性排斥反应组(36例)、功能稳定组(139例),30例健康供者作为对照组.应用流式细胞术检测外周血mHLA-GI、iHLA-G1的表达,酶联免疫吸附法检测血浆sHLA-G5的含量.结果 T淋巴细胞CD~+ mHLA-G1~+、CD8~+ mHLA-G1~+、CD4~+ iHLA-G1~+、CD8~+ iHLA-G1~+平均表达率在对照组分别为0.43%±0.19%、1.23%±0.41%、27%±13%、36%±14%,急性排斥反应组分别为:0.57%±0.34%、1.31%±0.56%、26%±8%、37%±17%,功能稳定组分别为0.61%±0.43%、1.39%±0.47%、26%±9%、37%±17%,3组间比较差异均无统计学意义(均P>0.05).外周血浆sHLA-G5表达在对照组为(25±14)ng/ml;急性排斥组术前为(24±15)ng/ml,术后为(34±21)ng/ml;功能稳定组术前为(25±11)ng/ml,术后为(56±32)ng/ml;急性排斥组和功能稳定组术前与健康组比较,差异无统计学意义(P>0.05),术后功能稳定组明显高于急性排斥组(P<0.05).结论 肾移植受者外周血存在一群比率较低的HLA-G~+ T淋巴细胞,mHLA-G1和iHLA-G1的表达与肾移植术后的排斥反应发生无关,sHLA-G5的高表达与排斥反应发生的减少有关.

Expression of human leucocyte antigen G in peripheral blood of kidney transplantation recipients

Objective To investigate the expression of non-classical major histocompatibility complex( MHC)-I molecule, human leucocyte antigen ( HLA ) G, including membrane-bound HLA-G (mHLA-G), intracellular HLA-G (iHLA-G) and soluble HLA-G (sHLA-G), in peripheral blood of surviving kidney transplantation recipients and understand the relevance between HLA-G and the function of transplanted organ, as well as the onset of acute rejection. Methods A longitudinal study was performed on 175 kidney transplantation recipients. Three groups were involved in this study, including acute rejection group (n = 36), function stable group (n = 139) and healthy control group (n = 30). The expression of mHLA-G1 and iHLA-G1 in the T lymphocytes of peripheral blood was detected by flow cytometry analysis and the sHLA-G5 level detected by ELISA. Results The average rate of CD4~+ mHLA-Gl~+ , CD8~+ mHLA-Gl~+ , CD4~+ iHLA-Gl~+ , CD8~+ iHLA-Gl~+ in T lymphocytes of healthy control group was 0. 43% ±0. 19% , 1. 23% ±0.41% , 27% ± 13% and 36% ± 14% respectively. That of acute rejection group was 0. 57% ± 0. 34% , 1. 31% ± 0. 56% , 26% ± 8% and 37% ± 17% ; that of function stable group was 0. 61% ± 0.43% , 1. 39% ±0.47% , 26% ±9% and 37% ± 17% respectively. There was no significant difference among the three groups (all P >0. 05). The average of sHLA-G5 levels in plasma of control group was (25±14) ng/ml, acute rejection group (24 ± 15) ng/ml (pre-operative) and (34±21) ng/ml (postoperative) , function stable group (25 ±11) ng/ml (pre-operative) and (56 ±32) ng/ml (post-operative). There was no significant difference among the three groups ( pre-operative, P > 0. 05 ) . The average of sHLA-G5 levels in plasma of function stable group was higher than that of acute rejection group (postoperative, P < 0. 05) . Conclusion There is a subset of CD4~+ HLA-G1~+ and CD8~+ HLA-G1~+ T lymphocytes with low percentage in peripheral blood of those surviving kidney transplantation recipients. The expressions of mHLA-G1 and iHLA-G1 have no relevance with the onset of acute rejection. sHLA-G5 is correlated with acute rejection in peripheral blood of surviving transplantation recipients.