Mechanism of hepatitis B virus infection of trophoblast cells and hepatitis B virus intrauterine infection / 中华传染病杂志

ABSTRACT

1.0?10~7 copies/mL. The HBsAg IHC staining positive cells could be observed in 6 placental tissues and 3 fetus' liver tissues,and HBcAg was also positive in 1 case of fetus' liver tissue.After co-incubating the tropho- blastic cells and HBV DNA positive serum in vitro,HBsAg expression and HBV DNA could be detected.Apoptosis of HBV-infected trophoblastic cells increased,which was demonstrated by in vivo and in vitro experiments and the apoptosis of placental cells was correlated with the cord blood HBV DNA level.The results of in vitro experiments showed that the apoptosis of trophoblastic cells increased with the elongation of infection time.After 6 months,1 of 12 newborns was positive for HBsAg,HBeAg and anti-HBc,6 was positive for anti-HBs.Conclusions The mechanism of HBV intra-uterine infection may be that HBV breaches the placental barrier and infects the fetus.The localization and replication of HBV in fetal tissues and organs are probably the important factors of chronic HBV infections in neonates.The apoptosis of trophoblastic cells may be the protective mecha- nism for the placental barrier to block the HBV intra-uterine transmission.