中文摘要：

目的研究HBV（hepatitis B virus）感染胎盘和正常胎盘在HBxAg（hepatitis B x antigen）蛋白表达上的不同,探讨HBxAg在HBV宫内感染中可能发挥的作用。方法选择24例已证实发生宫内感染的HBsAg（hepatitis Bsurface antigen）阳性孕妇（感染组）和10例正常健康孕妇（对照组）的胎盘组织,应用免疫组织化学SP染色法,检测各组胎盘中HBxAg的表达,用TUNEL法检测细胞凋亡情况。结果在HBV感染组的胎盘中可检测到HBxAg的表达,且高复制组（HBV DNA〉1×103拷贝/mL）染色吸光度值明显高于低复制组（HBV DNA〈1×103拷贝/mL）,差异有统计学意义（P〈0.05）;HBV感染高复制组细胞凋亡指数低于低复制组和对照组,差异有统计学意义（P〈0.01）。结论 HBxAg/抗细胞凋亡是HBV DNA高复制孕妇发生宫内感染的可能机制,而HBV DNA阴性孕妇存在不同的作用机制。

英文摘要：

Objective To study the difference of hepatitis B x antigen（HBxAg） expression level in hepatitis B virus（HBV）-infected placenta and normal placenta and then discuss the possible role of HBxAg in intrauterine infection.Methods We selected 24 full-term pregnant women who had been verified with intrauterine infection [hepatitis B surface antigen（HBsAg） positive] as the infected group and 10 normal full-term pregnant women as the control group.We used immunohistochemical staining method（SP staining method） to test the expression of HBxAg in trophoblastic cells and TUNEL method to detect apoptosis level.Results There was HBxAg expression in HBV-infected placenta;and the optical-density value in the high copy group（HBV-DNA copy level〉 1×103 copy/mL） was significantly higher than that in the low copy group（HBV-DNA copy level 〈1×103copy/mL）（P〈0.05）.TUNEL results showed that the apoptosis index was obviously higher in the normal group and the low copy group than in the high copy group（P〈0.01）.Conclusion HBxAg/antiapoptotic action in full-term pregnant women who have been infected by high level of HBV-DNA is a possible mechanism of intrauterine infection;and the pregnant women with negative HBV-DNA have different mechanisms.