Characterization of Dualtropic Type C Retroviruses Isolated from Spontaneous Non-T Lymphomas of SJL/J(v+) MICE

Abstract

Endogenous XC− viruses were isolated from non-T spontaneous lymphomas of SJL/J(v+) mice. These isolates were cloned by limiting dilution procedure and characterized for biological and immunological properties. At the electron microscope these isolates showed typical retrovirus type C morphology. Reverse transcriptase and immunofluorescence assays showed that these viruses were infectious for mouse and heterologous cell lines. Since some of the isolates induced cytopathic foci in mink lung cultures, they had properties similar to those described for other recombinant dualtropic viruses. Using a panel of monoclonal antibodies against gp 70 and p 15 (E) viral proteins, it was observed that the dualtropic XC− viral isolates had an antigenic profile different from that of SJL ecotropic XC+ virus.