SDF-1/CXCR4在滋养层细胞中的表达及其在母胎免疫耐受中的作用

The expression of SDF-1/CXCR4 in trophoblasts and their role in maternofetal immune tolerance

目的:研究趋化因子SDF1及其配体CXCR4在滋养层细胞中的表达及其在母胎免疫耐受中的作用。方法:取早孕期的绒毛,分离纯化培养绒毛外滋层养细胞(extravilloustrophoblast,EVT),用免疫细胞化学染色法检测SDF1与CXCR4在绒毛中的表达。用流式细胞术筛选源于滋养层细胞高表达CXCR4的绒癌细胞株用于体外微孔隔离室迁移实验,以分析SDF1的趋化活性。用免疫组织化学染色法检测早孕期绒毛及足月妊娠胎盘中SDF1及CXCR4的表达。结果:在EVT中可检出SDF1和CXCR4的表达,在一定范围内,SDF1的趋化活性与其浓度呈正相关(r=0.68,P<0.01)。10μg/L的SDF1趋化作用最强,最大趋化指数CI为1.62±0.12。在早孕期的绒毛及足月胎盘中,滋养层细胞的胞膜和细胞质中均检出SDF1和CXCR4的表达,但在足月胎盘中的表达强度明显低于早孕期的绒毛组织(P<0.01)。结论:SDF1/CXCR4在妊娠中发挥着重要作用,对维系母胎免疫耐受具有重要意义。

AIM： To investigate the expression of SDF- 1/CXCR4 in trophoblasts and their role in maternofetal immune tolerance. METHODS： Extra-villous trophoblasts were highly purified from villi of first trimester. The expression of SDF-1 and CXCR4 in villi was detected by immunocytochemcal staining. A chorioepithelioma cell line from trophoblasts with high expression of CXCR4 was screened by flow cytometry to test the chemotaxis of SDF-1 in transwell. The expression of SDF-1 and CXCR4 in villi of first trimester and placentas of last trimester was detected by immunonistochemical staining. RESULTS： SDF-1 and CXCR4 were expressed in extra villous trophoblasts. In a certain coverage, the chemotactic activity of SDF-1 had positive correlation with its concentration （ r = 0.68, P 〈 0.01 ）, and the maximum CI （chemotactic index） was 1.62 ± 0. 12. CONCLUSION： SDF-1 and CXCR4 play an important role in gestation and they are also important in maternofetal immune tolerance during pregnancy.