Virologic characteristics of hepatitis B virus in patients infected via maternal-fetal transmission

Abstract

AIM:To determine whether HBV with the same characteristics causes dissimilar mutations in different hosts. METHODS: Full-length HBV genome was amplified and linked with pMD T18 vector. Positive clones were selected by double-restriction endonuclease digestion (Eco RⅠ and Hin dⅢ) and PCR. Twenty seven clones were randomly selected from an asymptomatic mother [at two time points: 602 (1 d) and 6022 (6 mo)] and her son [602 (S)], and the phylogenetic and mutational analysis was performed using BioEditor, Clustal X and MEGA software. Potential immune epitopes were determined by the Stabilized Matrix Method (SMM), SMM-Align Method and Emini Surface Accessibility Prediction. RESULTS: All of the 27 sequences were genotype C, the divergence between the mother and son was 0%-0.8%. Compared with another 50 complete sequences of genotype C, the mother and her son each had 13 specific nucleotides that differed from the other genotype C isolates. AA 1-11 deletion in preS1 was the dominant mutation in the mother (14/18). The 1762T/1764A double mutation existed in all clones of the mother, 3 of them were also coupled with G1896A mutation, but none were found in the son. 17 bp deletion starting at nucleotide 2330 was the major mutation (5/9) in the son, which caused seven potential HLA class Ⅰ epitopes and one B cell epitope deletion, and produced a presumptive new start codon, downstream from the original one of the P gene. CONCLUSION: The HBV strain in the son came from his mother, and discrepant mutation occurred in the mother and her son during infection.

Towards the complete eradication of mother-to-child HIV/HBV coinfection at Saint Camille Medical Centre in Burkina Faso, Africa

“…11 The probabilities of vertical transmission are also related to the title of HBsAg, anti-HBc antibodies, and HBV polymerase activity. 12,13 Nowadays, the life expectancy of HIV positive patients has increased considerably and their quality of life has been improved with the use of the new antiretroviral three-therapies. Thus, in this context of chronic HIV disease, the problem arising from the chronic coinfection with HBV and HCV 14 is becoming important.…”

Maternal-child health

“…The vertical transmission is influenced by several factors such as maternal levels of HBV-DNA, HBeAg, variations in gene S of hepatitis B virus (HBV), duration of labor, and neonatal immune deficiency (Raniers et al;Shen et al, 2008;Singh et al, 2011;Sun et al, 2012). Gestational age during hepatitis B infection is an important factor affecting infant outcome (Chang, 2007).…”

Construction and expression of a recombinant eukaryotic expression plasmid containing the preS1-preS2-S genes of hepatitis B virus and the granulocyte-macrophage colony stimulating factor gene: A study of its immunomodulatory effects

“…The effector cells (4x10 7 cells) were incubated with stimulator cells at an effector-stimulator ratio of 10:1 for 7 days in culture medium containing 10 U/ml recombinant IL-2 (Peprotech, Rocky Hill, NJ, USA) at 37˚C in 5% CO 2 . The target cells were prepared by P815 cells (mouse mastocytoma cell line, Shanghai Institute of Biochemistry and Cell Biology of the Chinese Academy of Sciences) pulsed with HBV-specific peptide for 4 h at 37˚C in 5% CO 2 . The cytotoxic activity was tested by non-radioactive LDH release assay.…”

“…Approximately one-third of the world's 6.0 billion population is estimated to be infected with HBV (1), including 350-400 million chronic carriers of this virus (2). The HBV vaccine applied at present is primarily composed of HBsAg (S protein) expressed by Chinese hamster ovary (CHO) cells and beer yeast.…”