Heterogeneity analysis of the hepatitis B virus genome in intrauterine infection

Abstract

There are many factors leading to intrauterine infection with hepatitis B virus (HBV). These factors include viral structure, HBV mutations, HBV DNA level, placenta barrier, immune status of the mother, and susceptibility of the fetus. The purpose of this study was to investigate the possible relationship between intrauterine infection with and HBV mutations of the genome of the virus. In this study, HBsAg-positive mothers were divided into two groups: intrauterine infection group and non-infection group according to whether the newborn infants were infected or not. The intrauterine infection group included four pairs of mother and their newborn infants infected in utero, and non-infection group included five HBsAg-positive mothers. HBV sequences from the two groups were analyzed and compared. The predominant strains in the mothers and infants from the intrauterine infection group were not completely consistent. This suggested that both HBV predominant strains and minority strains in the mothers could infect their infants through intrauterine transmission. Some HBV mutations probably related to intrauterine infection were examined and it was found that the frequencies of mutations were low in isolates of the virus of infants from the intrauterine infection group and high in the non-infection group. These results suggest that some strains of HBV from the mother may be transmitted selectively to the fetus in utero because of viral heterogeneity. The strains without screened mutations such as P21L in the pre-S1 region may infect the fetus more readily.

Low Prevalence of Occult Hepatitis B Infection Among Blood Donors in Beirut, Lebanon: Reconsider the Deferral Strategy of Anti-HBc Positive Blood Donors

“…The outer primers were HBVS1 and HBVS2 and inner primers were HBVS3 and HBVS4 (25,26). The first and second round amplifications were performed in a total volume of 50 µL, containing 1× reaction buffer, 0.2 mM dNTPs, 1.5 mM MgCl 2 , 0.4 µM of each primer, 0.5 µL of Taq DNA polymerase, and 10 µL of DNA.…”

High Conservation of Hepatitis B Virus Surface Genes during Maternal Vertical Transmission despite Active and Passive Vaccination

“…In our previous studies [14,15] , we analyzed the relationship between intrauterine HBV infection and virus gene heterogeneity by comparing HBV sequences from Fre quency of point mutation: the frequency of patients with a specific mutation divided by the total number of patients from 1 group (numbers of cases with percentages in parentheses). p values were assessed by Fisher's exact test and corrected with the Benjamini-Hochberg method.…”

“…HBV DNA was extracted using a commercially available kit (QIAmp DNA blood mini-kit, Qiagen Inc., USA) and then amplified with the high-fidelity PCR System (Roche Corporation) according to the manufacturers' specifications using the following primer pairs: 5 -CGGGATCCCATA-TTCTTGGGAACAAG-3 (nt2826-2844) and 5 -CACTGCAG-GGTTTAAATGTATACCCA-3 (nt839-821) [14] . The PCR conditions were as follows: 5 min at 94 ° followed by 35 amplification cycles of 45 s at 94 ° , 1 min at 60 ° and 2 min at 72 ° .…”

“…The characteristics of the viral genome from all pregnant women were not fully consistent, which may be related to the outcome of vertical transmission. We analyzed the relationship between HBV gene heterogeneity and intrauterine infection in previous studies, and we found that the fetuses from mothers in whose sera HBV strains had certain mutations were not easily infected [14,15] . However, there was possible confounding bias from the maternal serum HBeAg status because it was an important risk factor.…”

Hepatitis B and Pregnancy, the Scientific Basis for Perinatal Prevention

“…58,68 Recently, several studies have demonstrated the association between genetic polymorphisms and susceptibility of HBV infection. 73,74 Su et al 74 reported fewer mutations in the pre-S and S region of HBV isolated from infants infected in utero. [69][70][71] On the other hand, the interleukin-10 -1082 G allele was associated with reduced HBV intrauterine infection.…”