HLA-G与原因不明复发性流产

HLA-G诱导的母胎免疫耐受是保证胎儿免遭母体排斥、妊娠得以顺利进行的关键。HLA-G属非经典HLA-Ⅰ类抗原,可在胎盘绒毛外滋养细胞选择性高表达,主要通过与NK、T细胞表面的杀伤抑制性受体结合,激活胞内免疫受体酪氨酸抑制基序,抑制杀伤及细胞毒活性。滋养细胞HLA-G表达降低或异常表达,影响其与NK、T细胞的结合而阻碍抑制性信号转导,母胎界面出现NK细胞表型以及NK、T细胞功能异常、功能性细胞因子分泌改变等妊娠期免疫紊乱现象,造成母体对胚胎抗原的免疫攻击,导致引发原因不明复发性流产。

HLA-G and Unexplained Recurrent Spontaneous Abortion

Fetal-maternal immunotolerance induced by HLA-G is the pivot factor for successful pregnancy that embryo is not rejected by matrix.Human leucocyte antigen-G ( HLA-G) ,a kind of non-classical HLA-Ⅰ,initially identified as a molecule selectively high expressed on extravillous cytotrophoblasts ( EVCT) ,has been supposed to inhibit the killing activity and cytotoxicity of NK and T lymphocytes through combining with their killing inhibitory receptor and followed by activiating immonoreceptor tyrosine-based inhibitory motif.The decreased and abnormal expression of HLA-G on the surface of trophoblasts impact the combination with NK and T cells,impede the transduction of inhibitory signals.Accordingly,the immonological turbulences such as the phenotypes of NK and the immuno-functions of NK and T cells emerge along with immunological attack on embryo antigens,eventually unexplained recurrent spontaneous abortion is induced.