A Critical Analysis of the Available In Vitro and Ex Vivo Methods to Study Retinal Angiogenesis

Figure 1

Types of angiogenesis. (a) Sprouting angiogenesis. (1) Endothelial cells are activated by growth factors. (2) Activated endothelial cells release proteases that degrade extracellular matrix. (3) Endothelial cells migrate and proliferate. (4) Endothelial cells start to maturate into a new vessel. (5) Stabilization of the new vessel. (b) Intussusceptive angiogenesis. (1) Stable vessel. (2) Extension of a preexisting vessel wall into the lumen. (3) The new vessel wall proliferates and splits the preexisting vessel. (4) Stabilization of the new vessels.

(a)

(b)