Demonstration of a firm association between hepatitis B surface antigen proteins bearing polymerized human albumin binding sites and core-specific determinants in serum hepatitis B viral particles.
Hepatitis B viral particles (HB-VP) were purified from sera of chronic hepatitis B surface antigen (HBsAg) positive carriers by consecutive isopycnic and rate-zonal sedimentation in sucrose gradients. Their immunological properties [HBsAg, hepatitis B core antigen (HBcAg) and hepatitis B e-antigen (HBeAg) activities] were examined by a radioimmunoassay based upon the classical "sandwich principle". A double antibody specificity radioimmunoassay (DAS-RIA) was then developed to determine whether envelope proteins (HBsAg) with binding activity for polymerized human serum albumin (pHSA-BA) were associated with core-specific antigenicities (HBc/HBeAg). An e-antigen activity cosedimenting with intact HB-VP (negative for HBcAg reactivity) was detected in association with HBsAg and receptors for pHSA. The presence of HBcAg-specific determinant(s) on HBeAg molecules was also indicated by DAS-RIA. So, we postulated that such hepatitis B virion (HBV) specific molecules are involved in immune complexes with anti-HBc as antibodies in sera of patients with chronic HBV infection. To define the significance of these molecular forms in HB-VP morphogenesis, we studied the effects of a mild treatment with a chaotropic salt, NaSCN, on HB-VP-rich fractions (DNA polymerase positive). A small mol. wt HBeAg derived from HB-VP by dissociating treatment was detected. We found that core-specific determinants (HBe/HBcAg) were bound to large surface proteins (HBsAg) with pHSA-BA and therefore probably contained the pre-S sequence. The selective release from HB-VP of such molecular forms, which could be a product of the major S-region transcript, suggests that they may be components of complete virions.
M A
MA
Petit
F
F
Capel
J
J
Pillot
D001665:Binding Sites; D002499:Centrifugation, Density Gradient; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000032:analysis*; D006511:Hepatitis B Antigens / Q000032:analysis*; D006512:Hepatitis B Core Antigens / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006513:Hepatitis B e Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000187:drug effects / Q000276:immunology*; D006801:Humans; D012709:Serum Albumin / Q000276:immunology*; D013861:Thiocyanates / Q000494:pharmacology
D000939:Epitopes; D006511:Hepatitis B Antigens; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D012709:Serum Albumin; D013861:Thiocyanates; C024553:sodium thiocyanate