中文摘要：

目的 探讨HBsAg阳性孕妇胎盘乙型肝炎病毒（HBV）感染状况及其危险因素，了解TLR3在胎盘HBV感染中的作用。方法 采用ELISA检测孕妇血清HBsAg和HBeAg；荧光定量PCR定量检测孕妇血清HBV DNA；免疫组织化学SABC法检测胎盘组织中TLR3和瑚BsAg；非条件Logistic回归模型分析胎盘HBV感染的危险因素。结果 102例胎盘中有33例存在不同程度的HBV感染，且蜕膜细胞（Dc）、滋养层细胞（TC）、绒毛间质细胞（VMC）和绒毛毛细血管内皮细胞（VCEC）阳性率呈逐层下降趋势（趋势χ^2=16．67，P〈0．001），阳性率分别为32．4％（33／102），20．6％（21／102），18．6％（19／102）和8．8％（9／102）；胎盘HBV感染的危险因素为母亲血清HBV DNA阳性和胎盘TLR3阳性，OR值分别为6．865和0．103。结论 HBV可感染胎盘各层细胞，HBV经胎盘及胎儿的主要途径是经血和（或）细胞传递方式实现；母亲血清HBV DNA阳性是胎盘感染的危险因素，胎盘TLR3阳性是胎盘感染的保护因素。

英文摘要：

Objective To explore the state and risk factors of HI]sAg positive pregnant women placental tissue infection; and understand the role of TLR3 in placenta HBV infection. Methods HBsAg and HBeAg in pregnant women were determined by enzymelinked immunosorbent assay（ELISA） ; HBV DNA in pregnant woman were detected by Fluorescence Quantitative PCR （FQ-PCR） ; HBsAg and TLR3 in placenta were detected by immunohistochemistry ABC. Risk factors of placenta HBV infection were analyzed by logistic regression model. Results HBsAg were infected in 33 of 102 placenta. HBV infection rates decreased gradually from the maternal side to the fetal side（trend test χ^2 = 16.67, P〈0. 001）in the placenta cell layers. Maternal decidual cells（32.4% ） 〉trophoblastic cells（20.6 % ） 〉 villous mesenchymal cells（ 18.6 % ） 〉 villous capillary endothelial cells（ 8.8 % ）. Risk factors of placenta being infected HBsAg included TLR3 positive in placenta（OR = 0. 103） and HBV DNA positive in maternal serum（OR= 6. 865）. Conclusion HBV can infect placental tissue and probably duplicate in it. Main approach of HBV invading newborns via placenta is mediated by ＂cell transfer＂. HBV DNA positive in maternal serum is the risk factor of placenta infection. TLR3 positive in placenta can effectively protect placenta from HBV infection.