乙型肝炎病毒宫内感染机理的研究

目的　探讨乙型肝炎病毒 (HBV)宫内感染的可能机理。方法　应用PCR技术检测 5 9例乙型肝炎病毒表面抗原 (HBsAg)阳性孕妇的羊水、阴道分泌物及其新生儿脐血清中HBVDNA(研究组 ) ,10例乙型肝炎病毒标志物 (HBVM )阴性的正常孕妇及其新生儿为对照组。采用免疫组化ABC染色法检测两组孕妇胎盘组织中的HBsAg及乙型肝炎核心抗原 (HBcAg)的阳性率。 结果　 ( 1)研究组孕妇的羊水、阴道分泌物、新生儿脐血清中HBVDNA阳性率分别为 4 7 5 % ( 2 8/ 5 9)、5 2 5 % ( 31/5 9)、4 5 8% ( 2 7/ 5 9) ;对照组孕妇的羊水、阴道分泌物、新生儿脐血清中均未检出HBVDNA。 ( 2 )研究组孕妇胎盘组织中HBsAg及HBcAg的阳性率 ,呈现出由蜕膜细胞 ( 76 3%及 5 9 3% )、滋养层细胞 ( 72 9%及 5 5 9% )、绒毛间质细胞 ( 6 2 7%及 5 0 8% )至绒毛毛细血管内皮细胞 ( 5 2 5 %及 4 4 1% )依次递减的趋势 ;但其中有 4例孕妇胎盘组织中HBsAg及HBcAg的分布与上述特点相反。研究组孕妇有 32例羊膜细胞中检出HBsAg及HBcAg。对照组孕妇胎盘组织中的HBsAg及HBcAg检出率为零。结论　孕妇血中HBV主要是通过感染胎盘导致胎儿感染 ;但也可能存在胎盘以外的感染途径。

Study on the mechanism of intrauterine infection of hepatitis B virus

Objective To study the possible mechanism of intrauterine infection of hepatitis B virus (HBV) Methods HBV DNA was examined in amniotic fluid, and vaginal secretion of 59 HBsAg positive mothers and in cord blood of their neonates by PCR Ten negative hepatitis B virus marker (HBVM) mothers and their neonates were served as control HBsAg and HBcAg in placenta were examined by avidin biotin complex (ABC) method Results The detection rate of HBV DNA in amniotic fluid, vaginal secretion and neonatal cord blood of the study group were 47 5%(28/59), 52 5%(31/59) and 45 8%(27/59) respectively HBsAg and HBcAg in placenta was distributed in the following descending order: maternal decidual cells, trophoblastic cells, villous mesenchymal cells and villous capillary endothelial cells But the distribution was in reverse order in 4 placentas HBsAg and HBcAg were detected in amniotic epithelial cells in 32 mothers Conclusion The main route of HBV transmission from mother to fetus is transplacental, from maternal side of placenta to fetal side However, HBV intrauterine infection may take place through other routes