Hill J A, Melling G C, Johnson P M
Fearing Research Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Am J Obstet Gynecol. 1995 Jul;173(1):90-6. doi: 10.1016/0002-9378(95)90175-2.
Atypical expression of human leukocyte antigen histocompatibility molecules or complement regulatory proteins by placental trophoblast has been hypothesized as a mechanism for spontaneous abortion. The purpose of this study was to determine expression of these proteins by placental villous trophoblast and to identify leukocyte populations within uteroplacental tissues from women with their first spontaneous abortion, their fourth or more recurrent spontaneous abortion, and from women having elective pregnancy termination.
Fresh uteroplacental tissues were obtained at 6 to 9 weeks' gestation from eight women with their first spontaneous abortion, 20 women experiencing their fourth or more unexplained recurrent spontaneous abortion, and 20 women having an elective pregnancy termination. These tissues were analyzed immunohistochemically for human leukocyte antigen histocompatibility molecules (class I and II major histocompatibility complexes), complement regulatory proteins (CD46, CD55), and leukocyte phenotypes (CD45, CD3, CD14, CD56).
There was absence of cell surface expression of class I and II human leukocyte antigen molecules but strong trophoblast expression of complement regulatory proteins in all villous placental samples. Leukocyte infiltration was noted in all decidual specimens. The predominant decidual leukocyte population was CD3-negative, CD56-positive cells, except in four cases of recurrent abortion where the normal ratio (< or = 2:3) of CD14-positive macrophages to CD56-positive leukocytes was > 2:1. There was an unusual retention of maternal class II major histocompatibility complex-positive leukocytes within intervillous spaces attached to the apical surface of syncytiotrophoblast from one individual with recurrent abortion.
Our data do not support the hypothesis that some cases of recurrent spontaneous abortion result from atypical expression of human leukocyte antigen histocompatibility molecules or lack of complement regulatory protein expression by placental villous trophoblast. These data suggest that occasional cases of recurrent spontaneous abortion could be associated with an impaired CD56-positive leukocyte response in the early decidualized endometrium.
胎盘滋养层细胞上人类白细胞抗原组织相容性分子或补体调节蛋白的非典型表达被认为是自然流产的一种机制。本研究的目的是确定这些蛋白在胎盘绒毛滋养层细胞中的表达情况，并识别首次自然流产、第四次或更多次复发性自然流产的女性以及选择性终止妊娠的女性子宫胎盘组织中的白细胞群体。
在妊娠6至9周时，从8例首次自然流产的女性、20例经历第四次或更多次原因不明的复发性自然流产的女性以及20例选择性终止妊娠的女性中获取新鲜的子宫胎盘组织。对这些组织进行免疫组织化学分析，检测人类白细胞抗原组织相容性分子（I类和II类主要组织相容性复合体）、补体调节蛋白（CD46、CD55）以及白细胞表型（CD45、CD3、CD14、CD56）。
在所有绒毛胎盘样本中，I类和II类人类白细胞抗原分子均无细胞表面表达，但补体调节蛋白在滋养层细胞中有强烈表达。在所有蜕膜标本中均观察到白细胞浸润。蜕膜中主要的白细胞群体是CD3阴性、CD56阳性细胞，但在4例复发性流产病例中除外，这4例中CD14阳性巨噬细胞与CD56阳性白细胞的正常比例（≤2:3）大于2:1。在一名复发性流产个体的与合体滋养层顶端表面相连的绒毛间隙内，有母体II类主要组织相容性复合体阳性白细胞的异常留存。
我们的数据不支持某些复发性自然流产病例是由胎盘绒毛滋养层细胞上人类白细胞抗原组织相容性分子的非典型表达或补体调节蛋白表达缺失所致这一假说。这些数据表明，偶尔的复发性自然流产病例可能与早期蜕膜化子宫内膜中CD56阳性白细胞反应受损有关。
