Fig. 10. Hypothetical scheme of the `vasculogenic zone'. This scheme illustrates the concepts of the `vasculogenic zone', which is defined as a vascular mural zone containing EPCs and probably also multipotent mesodermal stem cells here. Although the CD34⁺/TIE2⁺/KDR⁺/VE-cadherin^- cells present in this zone differentiate into endothelial cells and form capillary-like sprouts from the vascular wall, the multipotent stem cells in this zone may serve as precursors of the in vitro and in vivo observed accumulation of macrophages. Obviously, they also have the capacity to differentiate into smooth muscle cells.