Expression of murine leukemia viruses in B-cell lymphomas of CWD/Agl mice

The inbred mouse strain CWD/Agl has a high incidence of spontaneous B-cell lymphomas characterized by gross splenomegaly and lymph node enlargement. The endogenous ecotropic retrovirus of CWD/Agl mice is expressed in the spleen within the first 2 weeks of age and in the thymus by 1 month of age. Endogenous xenotropic virus is expressed in the spleen and bone marrow of the earliest age group examined (4 months). Restriction enzyme analysis of DNA extracted from tumorous tissues suggests that mink cell focus-forming viruses are not required for B-cell lymphomagenesis in CWD/Agl mice. CWD/Agl mice provide an important new experimental model for the study of B-cell lymphoma.