Tcf12 balances the reconstitution and differentiation capacity of hematopoietic stem cell

Tcf12 has been identified as one of the main helix-loop-helix transcription factors that regulates T cell development from double negative to double positive stage transition. While, the function of Tcf12 in hematopoietic stem cells remains not investigated. In this study, we observed that Tcf12 is expressed in HSCs and targeted deletion of Tcf12 in hematopoietic cells results in increased frequency and absolute number of HSCs, but compromises the reconstitution capacity of HSCs. Further analysis reveals that Tcf12 is dispensable for the self-renewal of HSCs. The declined reconstituted capacity of Tcf12^-/- HSCs stems from the decrease in the ability to differentiate into lymphoid-primed multipotent progenitors, and furthermore B and T lineages.