vascularisation

Vascularisation, also spelled vascularization, is the process by which blood vessels form and are distributed within tissues. It enables perfusion, oxygen delivery, nutrient supply, and waste removal essential for tissue growth, repair, and homeostasis.

Two primary developmental pathways contribute to vascularisation: vasculogenesis, the de novo formation of blood vessels from endothelial progenitor cells during embryogenesis; and angiogenesis, the sprouting or remodeling of vessels from pre-existing vasculature in response to growth factors and physiological cues. In addition, arteriogenesis refers to the enlargement of arterial channels, and lymphangiogenesis to the growth of lymphatic vessels. These processes can occur during development, wound healing, and tissue regeneration, and they may be co-opted by pathological conditions such as cancer.

Vascular growth is governed by signaling networks that sense oxygen and metabolic needs. Hypoxia-inducible factors stimulate the production of angiogenic growth factors (notably vascular endothelial growth factor, VEGF) and other mediators (FGF, PDGF). Notch signaling, pericyte recruitment, and extracellular matrix remodeling coordinate vessel sprouting, stabilization, and maturation.

Clinical and research relevance includes cancer biology, where vascularisation supports tumor growth and metastatic spread and is a target for anti-angiogenic therapies; ischemic heart and limb diseases, where promoting vascularisation aims to restore perfusion; and tissue engineering, where achieving rapid, stable vascular networks is essential for graft survival and function.

Assessment of vascularisation uses histology and imaging methods such as microvessel density counting, Doppler ultrasound, multiparametric MRI, CT angiography, and newer molecular imaging approaches.