title: HBcAg expressed on the surface of circulating Dane particles in patients with hepatitis B virus infection without evidence of anti-HBc formation.
abstract: Circulating immune complexes composed of HBcAg and anti-HBc have been demonstrated recently in patients with hepatitis B virus replication. After dissociation of immune complexes by chaotropic ions, HBcAg was quantified radioimmunologically. In the present study, we describe 10 patients with hepatitis B virus replication, absent or delayed anti-HBc formation and exposed HBcAg in serum. Four of the 10 patients had acute hepatitis, and six patients had chronic persistent hepatitis. In seven of 10 patients, a secondary immune defect was apparent due to acquired immunodeficiency syndrome, leukemia, histiocytosis X, sarcoidosis or end-stage renal disease. Electron microscopy demonstrated that Dane particles from anti-HBc-negative patients were agglutinated after addition of monoclonal anti-HBc antibodies, whereas Dane particles from anti-HBc-positive sera did not show agglutination. Monoclonal HBsAg-specific antibodies aggregated Dane particles independent of the presence of anti-HBc. Circulating HBcAg was always associated with the Dane particle fraction after density gradient separation. Hepatitis B virus core proteins from patients with and without anti-HBc studied by immunoblotting after sodium dodecyl sulfate-gel electrophoresis showed identical patterns. Hepatocytes from anti-HBc-negative patients were positive for HBcAg but negative for immunoglobulin G by immunofluorescence technique. The data indicate that HBcAg may also be expressed on the surface of Dane particles, where it is commonly masked by anti-HBc.
authors.affiliation: Department of Internal Medicine, Klinikum Rudolf Virchow, Standort Charlottenburg, Freie Universität Berlin, Federal Republic of Germany.
authors.forename: B
authors.initials: B
authors.lastname: Möller
authors.forename: U
authors.initials: U
authors.lastname: Hopf
authors.forename: R
authors.initials: R
authors.lastname: Stemerowicz
authors.forename: G
authors.initials: G
authors.lastname: Henze
authors.forename: H
authors.initials: H
authors.lastname: Gelderblom
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D015153:Blotting, Western; D002499:Centrifugation, Density Gradient; D002648:Child; D002908:Chronic Disease; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000276:immunology*; D006512:Hepatitis B Core Antigens / Q000032:analysis*; D006515:Hepatitis B virus / Q000276:immunology* / Q000502:physiology; D006801:Humans; D008099:Liver / Q000276:immunology; D008297:Male; D008854:Microscopy, Electron; D014779:Virus Replication
chemical_list: D006512:Hepatitis B Core Antigens