Does rapid oligomerization of hepatitis B envelope proteins play a role in resistance to proteasome degradation and enhance chronicity?
This review discusses the nature of hepatitis B and C chronicity from a virological perspective. Work described in the literature and our in vitro studies of HBV polypeptide morphogenesis lead us to speculate about a role for HBsAg complex formation in immune evasion that may be especially important during the initial period of infection. Briefly, although viral structural proteins do eventually provide epitopes recognized by the host, we suggest that these HBs Ag complexes, which may themselves be refractory to proteasomal degradation, are an important way by which the virus shields its epitopes and evades early recognition by the cellular immune system. This suggests a central strategy by which the virus has evolved, structurally, to enable the establishment of persistent infection of its host. The concept offers an explanation for the nearly unidirectional and rapid kinetics whereby HBV proteins form multimers and generate a surplus of viral structures that have not been thought to serve any useful structural purpose.
Department of Microbiology and Immunology, Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, Doylestown, Pennsylvania 18901, USA. Tim.block@drexel.edu
Timothy M
TM
Block
Anand S
AS
Mehta
Baruch S
BS
Blumberg
Raymond A
RA
Dwek
D000818:Animals; D000939:Epitopes / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000737:chemistry / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000276:immunology*; D006801:Humans; D007700:Kinetics; D018448:Models, Immunological; D009842:Oligopeptides / Q000737:chemistry* / Q000276:immunology*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000276:immunology*
D000939:Epitopes; D006514:Hepatitis B Surface Antigens; D009842:Oligopeptides; D014759:Viral Envelope Proteins; D046988:Proteasome Endopeptidase Complex