Following secondary in vitro sensitization with AKR/Gross virus-induced tumors, AKR.H-2b:Fv-1b mice develop cytotoxic T lymphocytes (CTL) specific for AKR/Gross viral antigens. It has recently been determined that the responder status of AKR.H-2b:Fv-1b to AKR/Gross virus declines with age. The nonresponsiveness observed in AKR.H-2b:Fv-1b is similar to that observed in AKR.H-2b mice which (regardless of age) does not develop anti-AKR/Gross virus CTL. It was of interest to determine the ability of these congenic mouse strains to respond to other murine leukemia viruses (MuLV). This was accomplished by immunizing AKR.H-2b and young or moderately aged AKR.H-2b:Fv-1b with Friend-Moloney-Rauscher (FMR) virus-induced tumors, and assessing the ability of anti-FMR CTL to develop following secondary in vitro stimulation. It was observed that both AKR.H-2b and AKR.H-2b:Fv-1b developed specific anti-FMR virus CTL. Similarly, following tumor challenge AKR.H-2b mice were unable to prevent the outgrowth of a syngeneic AKR/Gross virus-induced tumor, but were able to reject a syngeneic FMR virus-induced tumor.
AKR murine leukemia virus Age Factors