Qureshi F, Jacques S M, Johnson M P, Hume R F, Kramer R L, Yaron Y, Evans M I
Department of Pathology, Hutzel Hospital, Wayne State University School of Medicine, Detroit, Mich., USA.
Fetal Diagn Ther. 1997 Jul-Aug;12(4):210-5. doi: 10.1159/000264470.
The cause of growth retardation in trisomy 21 and other autosomal trisomies is not known, but may be the result of defective cell proliferation, slowing of the cell cycle, or placental structural abnormalities. Abnormalities of the fetal cell cycle may be reflected in placental growth and can be detected using proliferating cell nuclear antigen (PCNA).
Twelve second-trimester and six third-trimester trisomy 21 placentas were examined histopathologically and stained immunohistochemically using antibodies to PCNA. Normal age-matched placentas were used as controls.
The second-trimester trisomy 21 placentas all exhibited many large irregular hypovascular villi. The third-trimester trisomy 21 placentas showed two patterns: (i) many large, irregular hypovascular villi, and (ii) relatively normal-appearing villi with only a few abnormal villi and focal hypervascularity. PCNA staining was significantly greater in second-trimester placentas when compared to third-trimester placentas for both trisomy 21 and controls. There was no significant difference in PCNA staining in trisomy 21 placentas when compared to the normal age-matched controls.
PCNA staining indicates no significant differences in proliferation between normal and trisomy 21 placentas. Trisomy 21 placentas show villus abnormalities, including hypovascularity.
21三体综合征及其他常染色体三体综合征中生长发育迟缓的病因尚不清楚，但可能是细胞增殖缺陷、细胞周期减慢或胎盘结构异常所致。胎儿细胞周期的异常可能反映在胎盘生长中，并且可以使用增殖细胞核抗原（PCNA）进行检测。
对12例孕中期和6例孕晚期的21三体综合征胎盘进行组织病理学检查，并用抗PCNA抗体进行免疫组织化学染色。将年龄匹配的正常胎盘用作对照。
孕中期21三体综合征胎盘均表现出许多大的不规则低血管绒毛。孕晚期21三体综合征胎盘表现出两种模式：（i）许多大的、不规则的低血管绒毛，以及（ii）外观相对正常的绒毛，只有少数异常绒毛和局灶性血管增多。对于21三体综合征胎盘和对照胎盘，孕中期胎盘的PCNA染色均显著高于孕晚期胎盘。与年龄匹配的正常对照相比，21三体综合征胎盘的PCNA染色无显著差异。
PCNA染色表明正常胎盘与21三体综合征胎盘在增殖方面无显著差异。21三体综合征胎盘表现出绒毛异常，包括低血管性。
