title: Sequence analysis of the HBV S protein in Chinese patients with coexisting HBsAg and anti-HBs antibodies.
abstract: The coexistence of hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs) in patients with hepatitis B virus (HBV) infection has been discovered and explained for several decades, but debate still exists. This study was to explore the relationship between this special serological pattern and mutations in S gene region. Fifteen patients with coexisting HBsAg and anti-HBs were selected as the experimental group, and 27 patients with HBsAg positive only were selected as the control group. The S gene region was amplified and sequenced. No significant differences were observed between the two groups with regard to age, gender, alanine aminotransferase level, HBsAg titer, genotype, and HBV DNA level. The patients from the two groups were infected with HBV of the genotype B and C. Compared with the control group, the experimental group showed a higher variability in amino acid within the N-terminal region and the MHR, especially the "a" determinant. The most frequent change in patients from the experimental group was located at positions s126. The coexistence of HBsAg and anti-HBs might be associated with the increased amino acid mutations in the "a" determinant. Further studies should be performed to determine the clinical implication of this serological pattern, including the binding of anti-HBs to HBsAg, escape from immune system, and efficacy of antiviral therapy.
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Ding
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.|Institute for Gastroenterology and Hepatology, Wuhan University Medical School, Wuhan, Hubei Province, P.R. China.
authors.forename: Hong-Gang
authors.initials: HG
authors.lastname: Yu
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.
authors.forename: Yan-Xia
authors.initials: YX
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.
authors.forename: Ning
authors.initials: N
authors.lastname: Cui
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.
authors.forename: Jin-Fen
authors.initials: JF
authors.lastname: Dai
authors.affiliation: Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, P.R. China.
authors.forename: Jie-Ping
authors.initials: JP
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D044466:Asian People; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens / Q000097:blood* / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics* / Q000302:isolation & purification; D019694:Hepatitis B, Chronic / Q000276:immunology / Q000473:pathology / Q000821:virology*; D006801:Humans; D057131:Immune Evasion; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D019562:Viral Load; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D000410:Alanine Transaminase
keywords: S gene; antibodies to HBsAg; hepatitis B surface antigen; variability