VEGF guides angiogenic sprouting utilizing endothelial tip cell filopodia

J Cell Biol. 2003 Jun 23;161(6):1163-77. doi: 10.1083/jcb.200302047. Epub 2003 Jun 16.

Abstract

Vascular endothelial growth factor (VEGF-A) is a major regulator of blood vessel formation and function. It controls several processes in endothelial cells, such as proliferation, survival, and migration, but it is not known how these are coordinately regulated to result in more complex morphogenetic events, such as tubular sprouting, fusion, and network formation. We show here that VEGF-A controls angiogenic sprouting in the early postnatal retina by guiding filopodial extension from specialized endothelial cells situated at the tips of the vascular sprouts. The tip cells respond to VEGF-A only by guided migration; the proliferative response to VEGF-A occurs in the sprout stalks. These two cellular responses are both mediated by agonistic activity of VEGF-A on VEGF receptor 2. Whereas tip cell migration depends on a gradient of VEGF-A, proliferation is regulated by its concentration. Thus, vessel patterning during retinal angiogenesis depends on the balance between two different qualities of the extracellular VEGF-A distribution, which regulate distinct cellular responses in defined populations of endothelial cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Astrocytes / cytology
  • Astrocytes / metabolism
  • Cell Differentiation / physiology*
  • Cell Division / drug effects
  • Cell Division / physiology
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Endothelial Growth Factors / metabolism*
  • Endothelial Growth Factors / pharmacology
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / growth & development*
  • Endothelium, Vascular / metabolism
  • Mice
  • Mice, Knockout
  • Neovascularization, Physiologic / drug effects
  • Neovascularization, Physiologic / physiology*
  • Organ Culture Techniques
  • Pseudopodia / drug effects
  • Pseudopodia / metabolism*
  • Pseudopodia / ultrastructure
  • Retina / cytology
  • Retina / growth & development*
  • Retina / metabolism
  • Retinal Artery / cytology
  • Retinal Artery / growth & development*
  • Retinal Artery / metabolism
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factor Receptor-2 / drug effects
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism

Substances

  • Endothelial Growth Factors
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factor Receptor-2