Bendon Robert W, Coventry Susan, Thompson Matthew, Rudzinski Erin R, Williams Elizabeth M, Oron Assaf P
1 Department of Pathology, Kosair Children's Hospital, Louisville, KY 40202, USA.
2 Department of Laboratories, Seattle Children's Hospital, Seattle, WA 98105, USA.
Pediatr Dev Pathol. 2015 Sep-Oct;18(5):362-8. doi: 10.2350/14-12-1582-OA.1. Epub 2015 May 13.
Deposition of the complement split product C4d is a phenomenon studied extensively as a marker for complement activation in antibody-mediated transplant rejection. C4d also is observed in placental disease processes including spontaneous abortion, infarct, and villitis of unknown origins. Massive chronic intervillositis is a rare placental abnormality associated with increased risk of growth restriction, fetal death, and recurrent fetal loss. In this study, we evaluated C4d immunostaining in placentas with accumulation of intervillous monocytes with and without villitis. Archived placentas from Kosair Children's Hospital (Louisville, KY) and Seattle Children's Hospital (Seattle, WA) were selected and divided into 4 groups, 16 cases of intervillositis with complicated pregnancy, 15 cases of uncomplicated intervillositis, 20 cases of complicated villitis, and 13 cases of uncomplicated villitis, all with varying degrees of monocytic cells in the intervillous space. Representative specimen blocks were immunohistochemically stained for C4d. The percentage of positive staining of the microvillous surface of the syncytiotrophoblast was scored by five pathologists, and the following consensus score was determined: 0 = 0% to 5%; 1 = 5% to 25%; 2 = 25% to 75%; and 3 ≥ 75%. C4d immunostain localized to the microvillous border of syncytiotrophoblast in many of the placentas. C4d staining was more strongly associated with intervillositis than with villitis (odds ratio: 6.3; confidence interval: 2.1-18.7; P = 0.001).
补体裂解产物C4d的沉积作为抗体介导的移植排斥反应中补体激活的标志物，已得到广泛研究。在包括自然流产、梗死和不明原因绒毛炎在内的胎盘疾病过程中也观察到了C4d。大量慢性绒毛间炎是一种罕见的胎盘异常，与生长受限、胎儿死亡和复发性流产风险增加有关。在本研究中，我们评估了伴有或不伴有绒毛炎的绒毛间单核细胞积聚的胎盘中C4d的免疫染色情况。选取了来自科赛尔儿童医院（肯塔基州路易斯维尔）和西雅图儿童医院（华盛顿州西雅图）的存档胎盘，并将其分为4组：16例伴有复杂妊娠的绒毛间炎、15例无并发症的绒毛间炎、20例伴有并发症的绒毛炎和13例无并发症的绒毛炎，所有病例的绒毛间隙均有不同程度的单核细胞。对代表性标本块进行C4d免疫组化染色。由五位病理学家对合体滋养层微绒毛表面的阳性染色百分比进行评分，并确定以下共识评分：0=0%至5%；1=5%至25%；2=25%至75%；3≥75%。在许多胎盘中，C4d免疫染色定位于合体滋养层的微绒毛边界。C4d染色与绒毛间炎的相关性比与绒毛炎的相关性更强（优势比：6.3；置信区间：2.1-18.7；P=0.001）。
