The Fv-2r Resistance Gene in Mice: Its Effect on Spleen Colony Formation by Friend Virus- Transformed Cells 1, 2, 3

ABSTRACT-To determine the mechanism by which the reces· slve Fv-2r gene confers complete resistance to spleen focus formation and to the induction of early splenomegaly characteris-tic of the Friend virus (FV) disease syndrome, we compared the parameters of FV infection in susceptible DBA/2 (D2) (Fv·1", Fv-2") and partially congenic D2.Fv·2 ' (Fv-1", Fv-2r) mice. After infecting these mice with N-tropic FV complex, we followed the replication of spleen focus-forming virus (SFFV) and the generation of SFFV-transformed tumor colony-forming cells (CFC) in their spleens. By both parameters D2.Fv-2r mice were 20- to 100-fold less suscepti-ble than DBA12 controls, but the inhibition was only partial. Transplantation of washed spleen cells from SFFV-infected DBA/2 mice resulted In equal growth and recovery. of tumor CFC from both D2.Fv-2 ' and Fv-2· ' mice. However, these tumor cells grew as colonies in Fv-2 " mice, whereas they grew diffusely in the spleen