The role of lymphoid and haematopoietic target cells in viral lymphomagenesis of C57BL/Ka mice. I. Susceptibility to viral replication.

The influence of several parameters on the capacity of C57BL/Ka mouse haematopoietic cells to support replication of the radiation leukemia virus (RadLV) has been examined. Although replication of the virus is strongly thymotropic, the bone marrow and spleen are also susceptible when infection is initiated at birth rather than in adult life. Irradiation transiently restores the susceptibility of adults almost to the neonatal level. Neonatal thymectomy does not diminish the capacity of marrow cells to support virus replication, indicating that the migration of infected thymus cells back to the marrow is not responsible for the observed effect. Bone marrow cells in which viral antigens are no longer detectable yield infectious virus after intrathymic inoculation, suggesting the existence of a cryptic state of virus infection.