Inflammatory signaling plays a critical role in vertebrates embryonic hematopoiesis

 

Although it has been well studied that inflammatory signaling is essential role for stress hematopoiesis, its role in embryonic normal hematopoiesis remains unknown. He et al. found inflammatory signaling is critical in zebrafish and mouse embryonic hematopoiesis without infection or pathological inflammation. The article was published on Blood, recently.

 

During stress hematopoiesis in adult bone marrow, inflammatory signaling works either though promoting cell proliferation or inducing differentiation of hematopoietic stem and progenitor cells (HSPCs) to myeloid or lymphoid cells. In this study, researchers found inflammatory signaling is necessary and sufficient for emergence of embryonic HEPCs, which are mainly derived from hemogenic endothelium (HE) via the endothelial-to-hematopoietic transition (EHT). Further investigation showed a series of signaling that mediates the generation of hemogenic endothelium-derived HSPC: inflammatory signaling regulates this process via conserved TLK-NFκB core signaling, followed by the activation of Notch pathway, a critical signaling for HSPC specification. The findings revealed the role of inflammatory signaling in normal hematopoiesis in vertebrates, provides a potential new strategy for generation of HSPCs in patients with bone marrow failure.

 

Reference:
Blood. 2014 Dec 24. pii: blood-2014-09-601542.