title: Identification of hepatitis B surface antigen variants with alterations outside the "a" determinant in immunized Singapore infants.
abstract: Vaccine-associated hepatitis B surface antigen (HBsAg) mutations have been mainly identified within the "a" determinant (aa 124-147). Now changes have been detected that are located outside the "a" determinant from immunized Singapore infants born to hepatitis B virus (HBV) carrier mothers. These include Asn116 to Thr116, Val118 to Ala118, Pro120 to Ser120, Ala159 to Val159, Phe183 to Cys183, and Val184 to Ala184. Decreased binding to "a" determinant-specific monoclonal antibody was observed for variants Pro120 to Ser120, Ala159 to Val159, and Phe183 to Cys183. Unlike other HBsAg variants, the Asn116-to-Thr116 HBsAg variant had the wild type threonine in the infant, whereas the mutated asparagine was found in the mother. Vertical transmission is indicated for Phe183-to-Cys183 and Val184-to-Ala184 HBsAg variants, as they were found in both the infants and mothers. Detailed analysis of these HBsAg variants would provide further understanding of the antigenic structure of HBV.
authors.affiliation: Ransome Research Laboratory, Department of Clinical Research, Ministry of Health, Singapore.
authors.forename: O
authors.initials: O
authors.lastname: Chong-Jin
authors.forename: C
authors.initials: C
authors.lastname: Wei Ning
authors.forename: K
authors.initials: K
authors.lastname: Shiuan
authors.forename: L
authors.initials: L
authors.lastname: Gek Keow
mesh_terms: D000293:Adolescent; D000911:Antibodies, Monoclonal; D000940:Antigenic Variation; D002648:Child; D002675:Child, Preschool; D000939:Epitopes / Q000235:genetics; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control* / Q000635:transmission* / Q000821:virology; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens / Q000235:genetics* / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006515:Hepatitis B virus / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D009154:Mutation; D011247:Pregnancy; D012846:Singapore
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines