Expression data from cultured c-Kit+Sca-1+Lin- (KSL)cells

The Notch signaling pathway plays a critical role in regulating the proliferation and differentiation of stem and progenitor cells including hematopoietic stem and progenitor cells (HSPCs). Notch receptors and ligands are expressed in BM stromal and hematopoietic cells. A large body of evidence has demonstrated that activating Notch signaling enhances HSCs self-renewal and facilitates its expansion ex vivo. We report that an endothelium-targeted soluble Notch ligand, the DSL domain of mouse Delta-like 1 fused with a RGD motif (mD1R), efficiently promotes the expansion ex vivo of mouse bone marrow HSPCs in a Notch signaling and endocytosis dependent manner. HSPCs expanded in the presence of mD1R kept long-term HSPC repopulation capacity.

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