A Leukemogenic Filtrable Agent from Chemically-Induced Lymphoid Leukemia in C57BL Mice

Abstract

Thymic lymphomas were induced in 60% of C57BL mice fed with 7,12-dimethylbenz(a)anthracene [DMBA] dissolved in polyethylene glycol 400, the mean latent period from the start of the DMBA feedings being 176 days. Three series of cell-free filtrates prepared from the DMBA-induced lymphomas Were leukemogenic, producing 15-27% lymphomas in the tested mice. Serial cell-free passages of the original filtrate-induced lymphomas revealed a similar leukemogenic activity of 10-30%.