Leukemia virus suppression of antibody-forming cells: ultrastructure of infected spleens.

Infection of adult BALB/c mice with Friend disease virus results in a leukemia-like disease characterized by erythropoietic changes and splenomegaly. A marked depression of formation of cellular and serum antibody occurs in infected animals. Electron-microscopic examination of the ultrastructure of spleen sections from infected mice with depressed immunity revealed that virus particles can be detected only in immature blastlike lymphoid cells and not in plasmocytes characteristic of the immune response in spleens of noninfected mice immunized with sheep erythrocytes.