title: [Antigenicity of major hydrophilic region II of hepatitis B virus surface antigen].
abstract: OBJECTIVE
  To study whether the substitutions at the major hydrophilic region II (MHRII) of hepatitis B surface antigen (HBsAg) will impair the antigenicity of HBsAg.
  
  
  METHODS
  Four recombinant plasmids expressing mutant HBsAg (mtHBsAg) P1120T, C121S, K122I and T123N were constructed. HepG2 cells were transfected with the four plasmids and a plasmid expressing G145R HBsAg. The immunoreactivity of the cells expressing mtHBsAg with P1120T, C121S, K122I, T123N and G145R were detected by immunofluorescence (IF) staining and ELISA with 4 antibodies and 7 HBsAg diagnostic kits respectively.
  
  
  RESULTS
  mtHBsAg with P120T was recognized by mAb1 and mAb2. mtHBsAg with C121S and K122I was not recognized by any mAbs. mtHBsAg with T123N in lysates was recognized by mAb2, but not recognized in the supernatants.
  
  
  CONCLUSIONS
  Substitutions at amino acid positions 120-123 of HBsAg strongly impaired the antigenicity of HBsAg, a fact that was not appreciated previously.
authors.affiliation: Division of Clinical Immunology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Yong-jun
authors.initials: YJ
authors.lastname: Tian
authors.forename: Zheng-mao
authors.initials: ZM
authors.lastname: Zhang
authors.forename: Chang
authors.initials: C
authors.lastname: Xia
authors.forename: Shen-pei
authors.initials: SP
authors.lastname: Liu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yu
authors.forename: Hong-ping
authors.initials: HP
authors.lastname: Huang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Meng-ji
authors.initials: MJ
authors.lastname: Lu
authors.forename: Dong-liang
authors.initials: DL
authors.lastname: Yang
mesh_terms: D019943:Amino Acid Substitution; D000940:Antigenic Variation; D056945:Hep G2 Cells; D006514:Hepatitis B Surface Antigens / Q000235:genetics* / Q000276:immunology*; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology*; D006801:Humans; D009154:Mutation; D010957:Plasmids; D014162:Transfection
chemical_list: D006514:Hepatitis B Surface Antigens