Interferon Regulatory Factor-2 Regulates Hematopoietic Stem Cells

Objective: Interferon regulatory factor-2 (IRF-2) is highly expressed in hematopoietic stem cells (HSCs) in mouse bone marrow cells. The population of bone marrow Lin-c-Kit+Sca-1+(KSL) cells is increased in IRF-2-/- mice; however, there are less hematopoietic stem cells due to a reduction of the CD150+ population and type I interferon (IFN) signaling. We studied how HSCs lacking IRF-2 differentiate in bone marrow and peripheral blood.
Methods: To study the function of IRF-2 in HSCs, bone marrow cells from IRF-2-/- mice were transplanted into wild-type mice.
Results: Lineage cell population analysis showed that the B220 and CD19 populations from IRF-2-/- mouse bone marrow were enhanced in recipient mice. Conclusion: Bone marrow cells from IRF-2-/- mice can survive by lineage cell re-population. IRF-2 is important for the long-term repopulation of HSCs through not only the type I IFN response but also via the regulation of lineage-specific cell populations.