CD200R signaling inhibits pro-angiogenic gene expression by macrophages and suppresses choroidal neovascularization

Sci Rep. 2013 Oct 30:3:3072. doi: 10.1038/srep03072.

Abstract

Macrophages are rapidly conditioned by cognate and soluble signals to acquire phenotypes that deliver specific functions during inflammation, wound healing and angiogenesis. Whether inhibitory CD200R signaling regulates pro-angiogenic macrophage phenotypes with the potential to suppress ocular neovascularization is unknown. CD200R-deficient bone marrow derived macrophages (BMMΦ) were used to demonstrate that macrophages lacking this inhibitory receptor exhibit enhanced levels of Vegfa, Arg-1 and Il-1β when stimulated with PGE2 or RPE-conditioned (PGE2-enriched) media. Endothelial tube formation in HUVECs was increased when co-cultured with PGE2-conditioned CD200R(-/-) BMMΦ, and laser-induced choroidal neovascularization was enhanced in CD200R-deficient mice. In corroboration, signaling through CD200R results in the down-regulation of BMMΦ angiogenic and pro-inflammatory phenotypes. Translational potential of this pathway was investigated in the laser-induced model of choroidal neovascularization. Local delivery of a CD200R agonist mAb to target myeloid infiltrate alters macrophage phenotype and inhibits pro-angiogenic gene expression, which suppresses pathological angiogenesis and CNV development.

MeSH terms

  • Animals
  • Choroidal Neovascularization / genetics*
  • Choroidal Neovascularization / metabolism*
  • Choroidal Neovascularization / pathology
  • Dinoprostone / metabolism
  • Dinoprostone / pharmacology
  • Disease Models, Animal
  • Gene Expression*
  • Gene Knockout Techniques
  • Macrophages / metabolism*
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Mice
  • Mice, Knockout
  • Neovascularization, Pathologic / genetics*
  • Neovascularization, Pathologic / metabolism*
  • Phenotype
  • Retinal Pigment Epithelium / drug effects
  • Retinal Pigment Epithelium / metabolism
  • Signal Transduction*
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism

Substances

  • CD200 receptor, mouse
  • Membrane Glycoproteins
  • Vascular Endothelial Growth Factor A
  • Dinoprostone