Isolation and characterization of multipotent progenitor cells from the human fetal aorta wall

Recent evidence indicates that vascular progenitor cells may be the source of smooth muscle cells (SMCs) and endothelial cells (ECs). In the present study we isolated CD105(+), CD34(-) and fetal liver kinase(+) (Flk1(+)) cells from the human fetal arterial wall and demonstrated that they were vascular progenitors for both ECs and SMCs. In vitro, these cells cultured with vascular endothelial growth factor could differentiate into cells that expressed endothelial markers. Meanwhile, cells cultured with platelet-derived growth factor-BB could differentiate into cells that expressed smooth muscle markers. When transplanted into NOD/SCID mice, they contributed to neoangiogenesis in vivo during wound healing. These cells could also differentiate into osteogenic and adipogenic lineages in vitro. Hence multipotent vascular progenitor cells do exist in the arterial wall and they may have implications in the physical and pathological conditions of the vessel. Because these cells can be expanded in culture without obvious senescence for more than 30 population doublings, they may be an important source of ECs for cellular pro- or anti-angiogenic therapies.