| Ab-MLV (Abelson murine leukemia virus) induces pre-B cell lymphoma in vivo and transforms B lineage cells in vitro. The v-Abl protein, a tyrosine kinase, is required for the multi-step process of transformation. Many signaling pathways, as well as mutations affecting cellular genes, especially p53 and p19Arf, aid in the establishment of fully malignant, transformed cell lines. However, the way in which the kinase and cellular pathways are disrupted conferring the ability to transform specific cell types is not yet fully understood. Ab-MLV exhibits target cell specificity for B cells in certain stages of development. Thus, although a range of cell types can become infected, only cells at particular stages of differentiation are transformed. To explore how target cell specificity is controlled, I compared the susceptibility of B cell precursor populations from fetal and adult mice to Abelson virus. B cells develop in mice of both ages but do so under the influence of different cytokine signaling pathways. To further investigate the types of cells that are transformed by the virus, I also compared B cell precursors that develop in the absence of some critical signals using cell populations from mice lacking the gene encoding IL7, a component of the IL7 receptor or Flt3L. My results revealed that both fetal-derived and adult-derived cells are susceptible to the virus and that B cell precursors developing in the absence of IL7 signaling in the adult are highly compromised in their susceptibility to the virus. |
