Prevention of paralysis and suppression of lymphoma in wild mice by passive immunization to congenitally transmitted murine leukemia virus.

Lake Casitas wild mice were passively immunized as newborns with antiserum to congenitally transmitted murine leukemia virus. Immunization with immunoglobulin having a high neutralizing titer to ecotropic virus and a low titer to amphotropic virus correlated with the complete prevention of paralysis and a slight (25%), but statistically insignificant, reduction in the incidence of lymphoma. Occurrence of other tumor types and total mortality rate were not affected by immunization.