IDENTIFICATION OF MURINE LEUKEMIA VIRAL-ANTIGENS DETECTED ON MOUSE CELLS BY H-2 ALLOANTISERA

H-2 alloantisera contain antibodies against murine leukemia viral antigens, but the nature of the viral antigens on mouse cells which interact with these antibodies is not established. H-2 alloantisera apparently recognize components of MW 70,000-80,000 on mouse lymphocytes and leukemia cells. These components were also detected by a goat antiserum against the murine leukemia virus (MuLV) glycoprotein (gp70) and are therefore closely related to or identical with that viral protein. Although most H-2 alloantisera detected gp70-like molecules on lymphocytes and leukemia cells from a great variety of mouse strains, only 1 H-2 alloantiserum interacted with a gp70 component on cells from C57BL/10 and C57BL/6 mice. Animals such as C57BL/10 mice that lacked the component reacting with most H-2 alloantisera showed increased serum levels of anti-MuLV antibodies after injection of spleen cells having a gp70 component detectable by other H-2 alloantisera. Strains with cells reactive to antiviral antibodies in the H-2 alloantisera had low responses to MuLV antigens after a similar immunization procedure. Serum levels of anti-MuLV antibodies in both groups of mice, however, were increased after injection of Freund''s adjuvant. These observations suggest that anti-MuLV antibodies in mouse alloantisera may arise from a response to viral antigens on the immunizing cells and general stimulation of the immune system.