How hematopoietic stem/progenitors and their niche sense and respond to infectious stress

• Hematopoietic stem/progenitor cells contribute to blood supply during infection.
• Cytokines, pathogen-associated molecular patterns, and niche cells coordinately regulate the fate decision of hematopoietic stem/progenitor cells.
• The c-di-GMP/STING pathway attenuates hematopoietic stem cell function and mobilizes hematopoietic stem/progenitor cells.

Hematopoietic stem/progenitor cells (HSPCs) play important roles in fighting systemic infection as they supply immune cells in a demand-adapted manner. Various mechanisms govern HSPC responses to infection, including cytokine signaling, niche function, and direct sensing of pathogen-derived molecules by HSPCs themselves. Here we review recent advances in our understanding of HSPC responses to infection and also consider newly identified STING-mediated machinery recognizing bacteria-derived cyclic dinucleotides.