[Changes in transplantable cultures infected with mycoplasmas isolated from leukemic monkeys]

Four strains of mycoplasms isolated from monkeys with malignant lymphoma and haematosarcoma induced an apparent cytopathogenic effect (CPE) only in the FL culture in the first passage. No visible CPE was observed in L and HeLa, and also in FL cultures of the second and further passages infected with the same mycoplasm strains. However, the infected cultures differed reliably from the control ones by a higher index of cell alteration and by an increased mitotic activity. According to these indices they can be regarded as cultures with a latent CPE.