title: Subcellular localization of hepatitis B core antigen in relation to hepatocyte regeneration in chronic hepatitis B.
abstract: OBJECTIVE
  To test whether the dominant cytoplasmic expression of hepatitis B core antigen (HBcAg) in active chronic hepatitis B is secondary to liver damage and regeneration, the relationship between subcellular localization of HBcAg, liver inflammatory activity, and hepatocyte regeneration in chronic hepatitis B was studied.
  
  
  METHODS
  Correlation of the clinical and laboratory data with the topographical distribution of HBcAg was studied in 30 patients. The subcellular localization of HBcAg in relation to hepatocyte cell cycles was studied by double immunostaining of HBcAg and proliferating cell nuclear antigen.
  
  
  RESULTS
  Patients with predominant cytoplasmic HBcAg had significantly higher levels of biochemical and histological activities and proliferating cell nuclear antigen expression than patients with predominant nuclear HBcAg. The levels of proliferating cell nuclear antigen expression correlated positively with biochemical and histological activities and degrees of cytoplasmic HBcAg expression but negatively with degrees of nuclear HbcAg expression. Proliferating cell nuclear antigen expression was shown in 49% of hepatocytes with cytoplasmic HBcAg but in only 2% of hepatocytes with nuclear HBcAg.
  
  
  CONCLUSIONS
  These findings suggested that, following liver damage, the regeneration of surviving hepatocytes might cause the shift of intracellular HBcAg from nucleus to cytoplasm. As a result, the extent of nuclear HBcAg expression reduces with concomitant increase in cytoplasmic HBcAg expression.
mesh_terms: D000293:Adolescent; D000328:Adult; D002467:Cell Nucleus / Q000276:immunology; D002908:Chronic Disease; D003593:Cytoplasm / Q000276:immunology; D005260:Female; D006509:Hepatitis B / Q000276:immunology* / Q000473:pathology; D006512:Hepatitis B Core Antigens / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000276:immunology* / Q000473:pathology; D008115:Liver Regeneration; D008297:Male; D008875:Middle Aged; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism
chemical_list: D006512:Hepatitis B Core Antigens; D018809:Proliferating Cell Nuclear Antigen