Study on apoptosis of placental villous cells as a defense mechanism against intrauterine viral infections from mother to fetus

众所周知，胎盘具有防止病毒从母亲传播到胎儿的保护作用，这被称为“胎盘屏障”。然而，“胎盘屏障”的作用机制仍不十分清楚。孕妇感染人类T淋巴细胞病毒I型(HTLV-I)很少会传染给胎儿。本研究探讨HTLV-I感染与胎盘绒毛细胞凋亡的关系。获得的结果如下。1.TdT介导的UTP缺口末端标记法显示，HTLV-I阳性孕妇(n=8)胎盘绒毛细胞凋亡率显著高于HTLV-I阴性孕妇(n=8)。2.用HTLV-I感染的淋巴细胞(MT-2细胞)与胎盘绒毛细胞共培养，诱导胎盘绒毛细胞发生凋亡。3.HTLV-I阳性孕妇(n=69)和HTLV-I阴性孕妇(n=300)足月胎盘重量差异无统计学意义。两组婴儿的出生体重也没有差异。4.与胎盘绒毛细胞共培养可诱导HTLV-I感染的淋巴细胞(MT-2细胞)发生凋亡。

It has been well known that the placenta has a protective action against viral transmission from mother to fetus, which is called "the placental barrier". However, the mechanism of "the placental barrier'' is still not well elucidated. Human T-lymphotropic virus type I (HTLV-I) infection of pregnant women is rarely transmitted to fetuses. In the present study, the association between HTLV-I infection and apoptosis of the placental villous cells was investigated. The results obtained were as follows. 1. TdT mediated UTP nick end labeling method revealed that the incidence of apoptosis-positive placental villous cells in placentas from HTLV-I-seropositive pregnant women (n=8) was significantly higher than HTLV-I-seronegative pregnant women (n=8). 2. Apoptosis was induced in placental villous cells by co-culturing with HTLV-I-infected lymphocytes (MT-2 cells). 3. There was no difference in the weight of term placentas between the HTLV-I-seropositive pregnant women (n=69) and HTLV-I-seronegatives (n=300). The birth weight of the babies showed no difference between the two groups either. 4. Apoptosis was induced in HTLV-I-infected lymphocytes (MT-2 cells), when co-cultured with placenetal villous cells.