Development of neomycin-resistant WEHI-3B D+ murine cells as an in vivo model of acute nonlymphocytic leukemia.
pSV2 neomycin DNA was electroporated into exponentially growing WEHI-3B D+ cells, and clones containing integrated pSV2 neomycin DNA were selected by treatment with the antibiotic Geneticin. Southern analysis after Eco RI or Bam HI and Hind III digestion demonstrated that two clones, Y1 and Y2, stably incorporated a single copy of intact pSV2 neomycin DNA into different sites. Exposure of parental WEHI-3B D+ cells to retinoic acid, aclacinomycin A, or adriamycin resulted in their differentiation to mature granulocytic cells. Clone Y1 had growth kinetics and numbers of differentiated cells comparable to those of the parental line when exposed to these differentiation-inducing agents. Furthermore, this clone was leukemogenic in BALB/c mice. The disease presented as a moderate anemia, a peripheral blood granulocytosis, a shift in the differential to immature granulocytic forms, and a thrombocytopenia. Although there was no change in bone marrow cellularity, in situ hybridization to identify the presence of the neomycin resistance gene mRNA indicated infiltration of leukemia cells (up to 30%) into this tissue compartment. The observed hematological parameters were indicative of a late stage of disease resembling human acute nonlymphocytic leukemia. Clone Y1, therefore, would appear to be an in vivo model of acute nonlymphocytic leukemia that may be useful for the development of therapeutic strategies to more successfully treat these diseases. Because we have demonstrated that this line is capable of differentiation in vitro and can be stably carried in vivo, it would also be useful for the identification of therapeutic agents capable of initiating the differentiation of leukemia cells in situ.
Gamba-Vitalo
C
C
Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06510.
Carman
M D
MD
Sartorelli
A C
AC
D000818:Animals; D015139:Blotting, Southern; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D002999:Clone Cells / Q000145:classification / Q000187:drug effects / Q000473:pathology; D004195:Disease Models, Animal; D004351:Drug Resistance; D005260:Female; D005839:Gentamicins / Q000633:toxicity; D015470:Leukemia, Myeloid, Acute / Q000209:etiology / Q000235:genetics / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009355:Neomycin / Q000235:genetics; D009368:Neoplasm Transplantation; D010641:Phenotype; D014162:Transfection
D005839:Gentamicins; C010680:antibiotic G 418; D009355:Neomycin