Hepatitis delta virus attaches to human hepatocytes via human liver endonexin II, a specific HBsAg binding protein.
Recently we identified human liver endonexin II (EII) as a specific hepatitis B surface antigen (HBsAg) binding protein. To investigate whether EII is also able to interact with the HBsAg envelope of the hepatitis delta virus (H delta V), immunoprecipitation experiments were performed. H delta V particles could be co-precipitated by polyclonal rabbit anti-EII, but not by rabbit anti-glutathiontransferase (GST pi) antibodies from an H delta V-enriched fraction containing EII or GST pi. These findings suggest that H delta V particles were co-precipitated by anti-EII as a consequence of the binding between HBsAg present in the H delta V envelope and EII. Furthermore, binding of H delta V particles to human hepatocytes could be inhibited by incubation of the liver cells with rabbit anti-EII IgG or the H delta V particles with anti-idiotypic (anti-HBsAg) antibodies, developed spontaneously in rabbits immunized with EII. These findings support the assumption that small HBsAg present in the H delta V envelope is important for the attachment to the hepatocytes and that EII plays an important role in this process.
de Bruin
W
W
Division of Gastro-enterology and Liver Diseases, University Hospital Nijmegen, The Netherlands.
Leenders
W
W
Kos
T
T
Hertogs
K
K
Depla
E
E
Yap
S H
SH
D000268:Adhesiveness; D000818:Animals; D002352:Carrier Proteins / Q000502:physiology*; D006514:Hepatitis B Surface Antigens / Q000378:metabolism*; D003698:Hepatitis Delta Virus / Q000502:physiology*; D006801:Humans; D008099:Liver / Q000821:virology*; D011817:Rabbits; D011994:Recombinant Proteins / Q000378:metabolism
D002352:Carrier Proteins; D006514:Hepatitis B Surface Antigens; D011994:Recombinant Proteins