Characterization of a feline leukemia viral cell membrane antigen reactive with feline sera
Ruscetti, S.K.; Parks, W.P.
Journal of Immunology 119(6): 2194-2202
1977
ISSN/ISBN: 0022-1767 PMID: 72119 Document Number: 112949
Cats which have been infected with FeLV and which have recovered without disease or persistent viraemia are at a low to negligible risk for subsequent development of FeLV-associated neoplasia. To evaluate the immunological correlates of this protection, cat serum samples from various free-living populations were shown by immunoprecipitation of FL74 cell surface proteins to react with an 85 000 dalton cell surface protein, p85. All serum samples from non-viraemic cats with FL74 cell membrane immunofluorescence reactivity greater than 1:32 precipitated p85. It was shown that p85 contains determinants of the FeLV envelope glycoprotein. The reactivity to p85 could also be removed with FeLV-infected feline and nonfeline cells but not with cells nonproductively transformed by the feline sarcoma virus. These data strongly suggest that a major cell membrane antibody in feline serum is directed to the major FeLV envelope glycoprotein expressed on the surface of cells infected with FeLV but not FeSV. The relationship of this reactivity to the previously and presently defined anti-"FOCMA" reactivity is discussed.