The Pathology of Tumors and Other Lesions Induced in Rodents by Virus Derived from a Rat with Moloney Leukemia

Summary The morbid anatomic and histologic changes following inoculation of a sarcoma-inducing virus (derived from a rat with Moloney leukemia) into mice, rats, and hamsters are described. Changes similar to those in Friend disease, with proliferation of reticulum cells and erythroblasts, occurred in mice and rats. In mice, rats, and hamsters, there were also solid sarcomas and angiomatous tumors. There was also ectasia of lymph nodes and lymphatics which was associated with inflammatory, hyperplastic, or neoplastic lesions in the wall of the cysts. Attempts at serial transplantation of some of the solid tumors were successful in syngeneic mice and allogeneic hamsters. Tumors failed to grow in chickens or on the chorioallantoic membrane of embryonated eggs. The histogenesis of the tumors and ectatic lesions is discussed.