Figure 2.

HSPC maintenance under stress conditions. HSPCs in BM are sensitive to various stresses. On one hand, HSPCs can directly sense and respond to stress signals through specialized receptors. On the other hand, HSPC progeny cells and niche cells in the BM microenvironment can sense stress signals and convert the stress signals into the secretion of cytokines or chemokines, which in turn modulate HSPC maintenance. In addition, HSPCs themselves possess cytokine production ability that even overmatches that of their progeny cells in both magnitude and breadth. Therefore, HSPCs can also convert stress signals into cytokine or chemokine signals and modulate their maintenance in an autocrine manner. Consequently, HSPCs will undergo mobilization, proliferation, and myeloid-biased differentiation to rapidly produce myeloid cells, but their self-renewal and repopulating ability will be mitigated.