Cytotoxic activities of monoclonal antibodies against the envelope proteins of murine leukemia virus.

Monoclonal antibodies against the envelope proteins [gp70 and p15(E)] of murine leukemia virus react with the cell surface of virus-infected cells. The specificity and potency of these antibodies exceed those observed with conventional polyvalent antisera. In cytotoxic assays, certain of the monoclonal anti-gp70 antibodies demonstrate 1000-fold differences in their titer on leukemic and normal thymus cells.