Conversion of Danger Signals into Cytokine Signals by Hematopoietic Stem and Progenitor Cells for Regulation of Stress-Induced Hematopoiesis

Abstract

During an infection, the body increases the output of mature immune cells to fight off the pathogen. Despite convincing evidence that hematopoietic stem and progenitor cells (HSPCs) can sense pathogens directly, how this contributes to hematopoietic cell output remains unknown. Here we have combined mouse models with a single cell proteomics platform to show that in response to toll-like receptor stimulation, short-term HSCs and multipotent progenitor cells produce copious amount of diverse cytokines through the NF-κB signaling. Interestingly, the cytokine production ability of HSPCs trumps mature immune cells in both magnitude and breadth. Among cytokines produced by HSPCs, IL-6 is a particularly important regulator of myeloid differentiation and HSPC proliferation in a paracrine manner and in mediating rapid myeloid cell recovery during neutropenia. This study has uncovered a novel property of HSPCs that enables them to convert danger signals into versatile cytokine signals for regulation of stress hematopoiesis.

Files

Additional details