ABSTRACT
Blood vessel formation and development is a multiscale process, driven by the activation of endothelial cells (ECs, the main bricks of the capillary walls) induced by the action of suitable biochemical stimuli which are released both by environmental cells and by ECs themselves. Vascular progression involves two different mechanisms: vasculogenesis and angiogenesis (for a review, see [57, 358]). The former process mainly consists in the formation of a primitive vascular network, that emerges from a directed and autonomous migration, aggregation and organization of a dispersed population of endothelial cells. The latter consists instead of the formation of new vessels from an existing capillary or post-capillary venule. Angiogenic remodeling co-ordinates with the establishment of blood flow and can occur through sprouting, i.e., by the formation of new branches from the sides of existing capillaries, pruning, resizing of the capillary volume of the thickness of the capillary wall, or intussusception, i.e., by internal division of the vessel lumen.
