Inhibition of platelet-derived growth factor B signaling enhances the efficacy of anti-vascular endothelial growth factor therapy in multiple models of ocular neovascularization

Am J Pathol. 2006 Jun;168(6):2036-53. doi: 10.2353/ajpath.2006.050588.


'Vascular endothelial growth factor-A (VEGF-A) blockade has been recently validated as an effective strategy for the inhibition of new blood vessel growth in cancer and ocular pathologies. However, several studies have also shown that anti-VEGF therapy may not be as effective in the treatment of established unwanted blood vessels, suggesting they may become less dependent on VEGF-A for survival. The VEGF-A dependence of vessels may be related to the presence of vascular mural cells (pericytes or smooth muscle cells). Mural cell recruitment to the growing endothelial tube is regulated by platelet-derived growth factor-B (PDGF-B) signaling, and interference with this pathway causes disruption of endothelial cell-mural cell interactions and loss of mural cells. We have investigated the basis of blood vessel dependence on VEGF-A in models of corneal and choroidal neovascularization using a combination of reagents (an anti-VEGF aptamer and an anti-PDGFR-beta antibody) to inhibit both the VEGF-A and PDGF-B signaling pathways. We demonstrate that neovessels become refractory to VEGF-A deprivation over time. We also show that inhibition of both VEGF-A and PDGF-B signaling is more effective than blocking VEGF-A alone at causing vessel regression in multiple models of neovascular growth. These findings provide insight into blood vessel growth factor dependency and validate a combination therapy strategy for enhancing the current treatments for ocular angiogenic disease.

MeSH terms

  • Animals
  • Animals, Newborn
  • Disease Models, Animal
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / metabolism
  • Endothelium, Vascular / pathology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neovascularization, Pathologic*
  • Pericytes / metabolism
  • Proto-Oncogene Proteins c-sis / metabolism*
  • Retina / pathology*
  • Retinal Vein / metabolism
  • Signal Transduction
  • Vascular Endothelial Growth Factor A / antagonists & inhibitors*
  • Vascular Endothelial Growth Factor A / metabolism


  • Proto-Oncogene Proteins c-sis
  • Vascular Endothelial Growth Factor A