Under stress such as thrombocytopenia, SDF-1 and vascular endothelial growth factor (VEGF) activate metalloproteinases (MMP) like MMP-9, which convert membrane-associated Kit ligand to soluble Kit ligand (sKitL), thus promoting HSC entry into the cell cycle, mobilization to the vascular niche, and differentiation [47]. Here, VEGFA is linked to Thrombocytopenia.