Ecotropic virus involvement in spontaneous B-cell lymphomas of CWD/LeAgl mice.

The inbred mouse strain CWD/LeAgl, which has a high incidence of spontaneous B-cell lymphomas, expresses both ecotropic MuLV and MCF viruses. Studies indicated that the MCF viruses expressed in CWD tumors were characteristic of nononcogenic MCF viruses and that ecotropic MuLV may be the etiological agent in spontaneous B-cell lymphomagenesis. Somatically acquired proviruses of approximately the same size were detected in several tumor DNAs suggesting that integration of proviral sequences into specific regions of the mouse genome may be an important step in lymphomagenesis of this strain.