Cxcl8/PKC Signaling in the Endothelial Cell Niche Regulates Long-Term Hematopoietic Stem Cell Fate

The sinusoidal endothelial cell niche is a component of the hematopoietic microenvironment with an important role in regulating hematopoietic stem cell (HSC) fate. Mechanisms by which the niche control the long-term functional and phylogenetic diversity of the hematopoietic system are poorly understood. We performed gene expression profiling on FACS-purified endothelial cells from the zebrafish caudal hematopoietic territory (CHT), the sinusoidal endothelial niche equivalent to the mammalian fetal liver. Kdrl:GFP+lyve1b:DsRed+ CHT endothelial cells were compared to kdrl:GFP+lyve1b:DsRed- non-CHT endothelial cells by bulk RNA-seq and 106 genes were downregulated in the CHT with q Disclosures Zon: Amagma Therapeutics: Current equity holder in private company, Other: Founder; CAMP4 Therapeutics: Current equity holder in private company, Other: Founder; Celularity: Consultancy; Scholar Rock: Current equity holder in publicly-traded company, Other: Founder; Cellarity: Consultancy; Fate Therapeutics: Current equity holder in publicly-traded company, Other: Founder.