Identification of the major immunogenic structural proteins of human foamy virus.

We have identified the major immunogenic structural proteins of the human foamy virus (HFV), a distinct member of the foamy virus subfamily of Retroviridae. Radiolabelled viral proteins were immunoprecipitated from HFV-infected cells by foamy virus antisera of human and non-human primate origin. Precipitated viral proteins were in the range of 31K to 170K. Labelling of proteins with [14C]glucosamine or with [35S]methionine in the presence of tunicamycin, as well as endo-beta-N-acetylglycosaminidase H and F treatment of [35S]methionine-labelled proteins, revealed three viral glycoproteins of approximately 170K, 130K and 47K, most likely representing the env gene-encoded precursor, the surface glycoprotein and the transmembrane protein of HFV, respectively.