Differentiation and proliferation of hematopoietic stem cells are regulated by C/EBPβ, a transcription factor required for emergency granulopoiesis

Abstract

Under stress conditions such as infection, inflammation, and hematopoietic recovery following chemotherapy or transplantation, the hematopoietic system is required to meet the increasing demands, especially from myeloid cells. Therefore, an understanding of the molecular mechanism underlying stress hematopoiesis is clinically imperative. We previously showed that C/EBPβ, which is a transcription factor required for emergency granulopoiesis, plays a pivotal role at the level of hematopoietic stem/progenitor cells under stress conditions. Upon exposure to stress, the C/EBPβ protein is upregulated in the hematopoietic stem cells. A close examination of C/EBPβ knockout mice revealed that C/EBPβ regulates the proliferation and differentiation of hematopoietic stem cells at the cost of the self-renewing activity. Further elucidation of the functions and regulation of C/EBPβ in hematopoietic stem cells will facilitate an understanding of stress hematopoiesis.