[Aspects of megakaryocytic viral production in relation to lymphocytic leukemia in the rat].

Two viral populations BL/F (EL) and BL/F (SL) were derived from RadLV-Rs by propagation in rats where they induced respectively a generalized lymphoma in 5-6 weeks or a thymic lymphoma killing the animals in 5-6 months. In both cases, 10 days after inoculation of viral extract, numerous viral particles are present in the megakaryocytes (MKC) of the bone marrow and the spleen. Our results suggested a production rather than a passive accumulation of those particles by the MKC. The kinetics of blood platelet level for both leukemias showed a thrombocytopenia corresponding with the macroscopic development of the tumor. Therefore the evolution of the blood platelet level is not related to the MKC viremia. This suggests a lack of direct effect of virus BL/F on the MKC metabolism.