Induction of interferon in AKR mice by murine leukaemia viruses.

A high percentage of AKR mice develop spontaneous leukaemia which has shown to be associated with the early expression of ecotropic murine leukaemia virus (MuLV) and the subsequent expression of xenotropic as well as polytropic MuLVs. Generally, mice infected with any one of several groups of viruses, including MuLVs, have been shown to produce interferon (IF). However, we report here that AKR mice produce no IF, despite that fact that infectious, endogenous MuLV is expressed in these mice from birth.