The Detection Of HBV CccDNA And Clinical Implication In Placenta Of HBsAg Positive Pregnant Women

Objective: Hepatitis B virus(HBV) is mainly caused by Mother-to-infant vertical transmission. Intrauterine infection is one of important routes of HBV transmission, and the main causes of immunoprophylaxis failure. In this study,a new situ detection method was used to detecte the HBVcccDNA in HBsAg positive pregnant women placenta tissue, furtherly exploring the mechanism of mother-to-infant vertical transmission of hepatitis B virus, and studying the relationship between placeta and HBV intrauterine infection. Methods: 52 cases of HBsAg positive placenta tissue of women were collected as experimental group, production and delivery in Beijing No.302 Hospital and 5 cases of healthy pregnant women placenta tissues as negative control group, with HBsAg and HBcAg positive liver puncture samples as positive control group. Clinical data of pregnant women and newborns was collected, cut the size of the 2.0cm×2.0cm×1.5cm from fetal childbirth after 30 min in umbilical cord placenta tissues from the central, immediately fixed in 10% neutral formalin, after gradient alcohol dehydration, paraffin embedding, serial sections after the use of 4.5μm. Envision immunohistochemical staining method was used to detect HBsAg, HBcAg in the placenta tissue of various kinds of cells. In situ polymerase chain reaction method was used to detected HBV cccDNA of placenta tussues. Each experiment was set up the negative control group and positive control group. Put the birth within 24 h after femoral venous blood of HBsAg, HBeAg, or any HBV DNA positive as a symbol of neonatal intrauterine infection. Results: 1. In 52 cases of HBsAg positive women, a total of 21 cases of neonatal intrauterine were infected and the total infection rate was 40.38%(21/52). 2.HBeAg positive group of pregnant women had a total of 19 cases, and 17 cases of intrauterine were infected, infection rate was 89.47%(17/19) and was higher than the HBeAg negative group pregnant women intrauterine infection rate 12.12%(4/33). P < 0.05, the difference was statistically significant. The HBV infection rates were 77.78%(14/18) in 18 pregnant women with HBV DNA >104IU/ml, significantly higher than 25.00%(3/12)in the serum of the pregnant women with low viral levels group(102~104IU/mL), P<0.05, the difference was statistically significant. 2. HBsAg and HBcAg was negative in experimental placenta tissue with Immunohistochemical staining. HBsAg and HBcAg was positive in positive control group, and negative control did not see a positive signal. 3. The in situ polymerase chain reaction did not see the expression of HBV cccDNA in HBsAg positive women placental tissue, HBV cccDNA was positive in positive control group, and HBV cccDNA was negative in negative control group. Conclusions: Placental tissue may be not the main way to happen intrauterine infection, and intrauterine infections may occur through other means. The risk factors for HBV intrauterine infection need to be studied in the large sample size.