mineleukemia virus was studied on the surfaces of a variety of normal munine cell lines with a monospecific rabbit anti serum raised against purified Friend mumine leukemia virus

The expression of the major glycoprotein, gp7l , of mu mineleukemia virus was studied on the surfaces of a variety of normal munine cell lines with a monospecific rabbit anti serum raised against purified Friend mumine leukemia virus gp7l . Using viable cell membrane immunofluorescence, most established and early passage normal muminecell 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 muminecells tested not detectably expressing gp7l detenmi nants were BALB/3T3 lines. Although some Friend gp7l interspecies reactivity was discernible on normal munine cells, the principal reactivity was shown to be group spe cific. Fresh thymocytes from BALB/cJ (G1@-), C57BL/6J (G1@-), and 129/J (G1@+) mouse strains were also reactive with Friend gp7l antiserum, and this activity, as well as that of an antiserum prepared against purified AKR gp7l , were also group specific. An activity discriminating G1@+from G1@thymocytes was not observed with either Friend or AKR gp7l antisera.