原因不明复发性流产患者蜕膜NK细胞亚群特征研究

Expression patterns of NK cell subset in the decidua from unexplained recurrent spontaneous abortion

目的通过分析原因不明复发性自然流产(URSA)患者流产蜕膜组织中NK细胞亚群表型特征,探讨蜕膜NK细胞在URSA发病中的作用。方法选取URSA患者26例为URSA组,20例同期正常妊娠行人工流产者作为正常早孕组,采用流式细胞术分析蜕膜组织NK细胞亚群表型、比例及其抑制性受体CD94/NKG2A表达情况。结果蜕膜中CD3-CD56+NK细胞约占淋巴细胞的70%,是妊娠子宫蜕膜中淋巴细胞的主要类型,URSA组蜕膜NK细胞比例与正常早孕组无明显差异;正常早孕组蜕膜NK细胞主要为CD56brightCD16-亚群,约占80%;而URSA组CD56brightCD16-亚群比例为(72.2±15.2)%,明显低于正常早孕组,而CD56dimCD16+亚群比例(15.3±6.7)%,明显高于正常早孕组,均有统计学差异(P<0.05)。URSA组蜕膜CD56brightCD16-细胞亚群CD94/NKG2A表达显著低于正常早孕对照组(P<0.01)。结论 URSA的发生可能与其蜕膜NK细胞CD56brightCD16-和CD56dimCD16+亚群比例失衡有关,而且蜕膜CD56brightCD16-细胞亚群抑制性受体CD94/NKG2A表达明显降低,可能引起NK细胞异常激活,参与URSA妊娠母胎免疫耐受的破坏。

Objective To investigate the expression patterns of natural killer（NK） cells subset in the decidua from pregnant women with unexplained recurrent spontaneous abortion（URSA） and to explore the role of deeidua NK cells in URSA. Methods The decidua were obtained from 26 cases of pregnant women with URSA and 20 healthy pregnant women induced abortion with in- formed consent（control group）. The expression of immunophenotypic characteristics CD3 ,CD56,CD16 and the inhibitory receptor CD94/NKG2A on decidual NK cells were determined by flow eytometry. Results About 70% of the lymphocytes in decidua were CD3- CD56＋ NK cells. No significant differences in NK cell percentages were found between URSA and normal pregnancy control. The CD56bCD16- NK cells represented at least 800/oo of decidual NK cells in normal pregnancy and were therefore the major sub- set. The proportion of CD56bright CD16- subsets in the URSA group（72.2± 15.2）%,was significantly lower than the normal preg- nancy group, while the proportion of CD56dim CD16 ＋ subsets （ 15.3 ± 6.7） , was significantly higher than the control （P〈 0.05 ）. The expression of CD94/NKG2A on decidual CD56bghtCD16 subsets in the URSA group was significantly decreased as compared with those in the normal pregnancy control（P〈0.05）. Conclusion The deeidual CD56brghCD16 and CD56amCD16 subsets imbalance might correlate with occurrence of URSA. Depressed expression of the inhibitory receptor CD94/NKG2A on the decidual CD56brlght CD16- subsets could cause abnormal activation of NK cells,and might play an important role in the maternal-fetal immune tolerance destruction in USRA.