3060 – PDGFRΒ+ CELLS PLAY A DUAL ROLE AS HEMATOPOIETIC PRECURSORS AND NICHE CELLS DURING MOUSE ONTOGENY

Hematopoietic stem cell (HSC) generation in the aorta-gonad-mesonephros region requires HSC specification signals from surrounding microenvironment. In zebrafish, PDGF-B/PDGFRβ signaling controls hematopoietic stem/progenitor (HSPC) and is required niche. Little known about murine HSPC vivo whether involved. Here we show that PDGFRβ expressed distinct perivascular stromal layers mid-gestation dorsal aorta, its deletion impairs hematopoiesis. We demonstrate PDGFRβ+ cells play a dual role They act aortic niche to support HSPCs, addition, embryonic precursors give rise subset of HSPCs persist into adulthood. These findings provide crucial information for controlled production these clinically important vitro.