Blood vessels grow from adult bone marrow

Endothelial stem cells can persist into adult life, contributing to the formation of new blood vessels, but the origin and continued development of endothelial progenitors remains unclear. In February 1 Journal of Clinical Investigation, Morayma Reyes and colleagues from University of Minnesota Medical School, Minneapolis, USA, show that adult bone marrow stem cells can expand in vitro into a significant number of endothelial cells that engraft in vivo and contribute to neoangiogenesis.

Reyes et al. cultured multipotent adult progenitor cells (MAPCs) with VEGF and observed that they differentiated into CD34⁺, VE-cadherin⁺, Flk1⁺ cells — a phenotype that would be expected for angioblasts. These cells differentiated further into cells that expressed endothelial markers, functioned in vitro as mature endothelial cells and contributed to in vivo neoangiogenesis during tumor angiogenesis and wound healing (J Clin Invest 2002, 109:337-346).

"As MAPCs can be expanded...