Induction of Leukemia-associated Inhibitory Activity and Bone Marrow Granulocyte-Macrophage Progenitor Cell Alterations during Infection with Abelson Virus1

Neonatal and adult BALB/c mice were investigated in a longitudinal study for the acquisition of leukemia-associated inhibitory activity (LIA) interactions after inoculation with Abelson virus in vivo. Within 2 to 4 days after virus infection, the granulocyte-macrophage colony-forming cells from the bone marrow and spleen of the infected mice became insensitive to inhibition by LIA, even though colony morphology appeared normal. Shortly after, or simultaneously with, the detection of the colony-forming cell resistance phenomenon, LIA was found in bone marrow, spleen, and thymus cells. The abnormal inter actions appeared to be related to induction of lymphoma in BALB/c neonates and to a lymphoproliferative disease in adult BALB/c mice. In contrast, normal cellular interactions were noted in adult C57BL/6 mice which were not susceptible to the Abelson disease after virus inoculation and in untreated neonatal and adult BALB/c and adult C57BL/6 mice. Their colony-forming cells were sensitive to inhibition by LIA, and no LIA was detected in their bone marrow, spleen, and thymus cells. The abnormal cellular interactions are similar to those noted in human leukemia, lymphoma, and "preleukemia." This suggests that Abelson virus-infected mice can serve as a model for the study of LIA interactions.