IMMUNOFLUORESCENT ANALYSIS OF EXPRESSION OF RNA-TUMOR VIRUS MAJOR GLYCOPROTEIN, GP71, ON SURFACES OF NORMAL MURINE CELLS

Abstract

The expression of the major glycoprotein, gp71, of murine leukemia virus was studied on the surfaces of a variety of normal murine cell lines with a monospecific rabbit antiserum raised against purified Friend murine leukemia virus gp71. Using viable cell membrane immunofluorescence, most established and early passage normal murine cell lines were significantly reactive with the antiserum, irrespective of neoplastic transformation, strain genotype, or whether they were of embryonic or adult tissue origin. The only murine cells tested not detectably expressing gp71 determinants were BALB/3T3 [fibroblast] lines. Although some Friend gp71 interspecies reactivity was discernible on normal murine cells, the principal reactivity was group specific. Fresh thymocytes from BALB/cJ (GIX-), C57BL/6J (GIX-), and 129/J (GIX+) mouse strains were also reactive with Friend gp71 antiserum, and this activity and that of an antiserum prepared against purified AKR gp71 were also group specific. An activity discriminating GIX+ from GIX- thymocytes was not observed with Friend or AKR gp71 antisera.