Analysis of the in vivo vascular contribution potential of hemato-vascular progenitor cells derived from fetal stages of development

Hemato-vascular progenitor cells from the adult bone marrow can contribute to blood and vasculature when transplanted into adult irradiated recipient mice. Using this experimental model, high levels of hematopoietic reconstitution can be achieved, while contribution to vasculature is in general very limited. Here we tested if the developmental time of the donor cells and the recipient microenvironment constitute critical factors that determine the extension of contribution to the vasculature. We have used donor cells from AGM region, fetal liver and adult bone marrow. Cells were obtained from transgenic mice for the SCL-3énh construct that targets vasculature and hematopoietic stem cells, allowing cell lineage tracing in recipient mice. Cells were transferred into the blood stream of adult irradiated and busulfan-treated newborn recipient mice. Using flow cytometry and confocal quantitave microscopy analisys of the liver and kidney vasculature we show that foetal and BM derived progenitor cells contribute similarly to adult vasculature. However, when hemato-vascular progenitor cells are transferered into a new born enviroment, foetal derived cells have a more extended contribution potential to vasculature than adult bone marrow derived cells. This data can have implications for the selection on the donor/receptor ontogenic stage for efficient hemato/vascular transplantation. Supported by the Spanish Ministry of Education and Science Grant SAF2 07241 and SAF03448/to M.J.S., Junta de Andalucia PAI-CVI 295 supporting grant , Fellowship CONACYT179065 to A.M.G. and fellowhip I3P-CSIC to C.Q.