乙型肝炎病毒宫内传播机制的分子流行病学研究

A Molecular Epidemiologic Study on the Mechanism of Intrauterine Transmission of Hepatitis B Virus

为了解乙型肝炎病毒 ( HBV)宫内传播的危险因素与机制 ,笔者进行了病例对照研究与胎盘组织的免疫组化。收集陕西省妇幼保健院 2 4 2例 HBs Ag阳性的孕妇及其新生儿作为研究对象。结果显示 ,母亲 HBe Ag阳性 ( OR=32 .63)和先兆早产史 ( OR=2 2 .80 )是主要的危险因素。在 32例足月孕妇的免疫组化 HBs Ag阳性的胎盘组织中 ,HBs Ag阳性率在脱膜细胞层为 10 0 % ,滋养层细胞为 59.38% ,绒毛间质细胞为 65.50 % ,绒毛毛细血管内皮细胞为 39.38% ,表明 HBV感染从母面到胎儿血管呈逐渐下降趋势 ( P<0 .0 1)。而且绒毛毛细血管 HBs Ag阳性与婴儿宫内感染有关( OR=2 0 .86,P<0 .0 1)。根据上述结果 ,我们提出假设 :HBV宫内传播可能有两条途径 :经先兆早产等引起的胎盘血管渗漏的“血源传播”和 HBV经胎盘各层细胞“转移”至胎儿血循环的“细胞转移传播”。

A case- control study with exam ination of placentas using im munohistochem istry stain w as reported in this paper.In the Maternal and Children H ealth H ospita of Shanxi Province,2 4 2 consecutive HBs Ag positive mothersand theirbabies were selected assubjects and 1 1 0 placentas of HBs Ag positive mothersand2 5placentasof HBs Ag negativemothers during thedifferentperiod of pregnancy were collected for laboratory test.The results showed that maternal HBe Ag positivity (OR=32 .63) and history of threatened premature labor (OR =2 2 .80 ) were important risk factors.Among full- term placentas with HBs Ag positivity,HBs Ag(biomarker of HBV infection) positive rates were 1 0 0 % in decidual cell,59.38% in trophoblastic cell,65. 50 % in villous mesenchyme cell,and 39.38% in villous capillary endothelial cell (VCEC) with a decreasing trend (trend test,χ2 =30 .5,P<0 .0 1 ) from mothers to fetus whereas HBs Ag positive in VCEC was significently related to intrauterine infection (OR=2 0 .86,P<0 .0 1 ) .Results suggested that there mightbe two transmission routeson the mechanism of HBV intrauterine transmission,hemogenous by damage of placental vessels and cellular through placental cellular transferof HBV.