Vasculogenesis

Vasculogenesis is the process of blood vessel formation occurring by a de novo production of endothelial cells. It is sometimes treated as synonymous with angiogenesis but is often differentiated from it by the biologic mechanisms involved.

In the sense distinguished from angiogenesis, vasculogenesis is different in one aspect: whereas angiogenesis is the formation of new blood vessels from pre-existing ones, vasculogenesis is the formation of new blood vessels when there are no pre-existing ones. For example, if a monolayer of endothelial cells begins sprouting to form capillaries, angiogenesis is occurring. Vasculogenesis, in contrast, is when endothelial precursor cells (angioblasts) migrate and differentiate in response to local cues (such as growth factors and extracellular matrices) to form new blood vessels. These vascular trees are then pruned and extended through angiogenesis.

Vasculogenesis occurs during embryologic development of the circulatory system.

Vasculogenesis can also occur in the adult organism from circulating endothelial progenitor cells (derivatives of stem cells) able to contribute, albeit to varying degrees, to neovascularization. Examples of where vasculogenesis can occur in adults are:

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