Abstract
The humoral immune responses of NIH Swiss and SWR/J mice immunized with formalin-inactivated AKR or Gross murine leukemia virus, respectively, were examined. Both immune sera had high titers of antibodies detectable in radioimmune precipitation assays using [3H]leucine-labeled AKR virus and in radioimmunoassays using purified virion components. The predominant antibody titers were directed against gp71 and pl15(E). The immune response against gp71 was predominantly type-specific, whereas the reactivity with pl15(E) was predominantly group-specific. A weak immune response against p15 was also detected. Both sera were cytotoxic against cells replicating the AKR-Gross virus type but not against cells replicating Friend murine leukemia virus. This cytotoxicity could be specifically blocked with purified gp71 of AKR murine leukemia virus. Sera from immune NIH Swiss mice neutralized AKR virus, but did not neutralize Rauscher, Scripps, or wild mouse leukemia virus.