Involvement of macrophage chemotactic protein-1 and interleukin-1beta during inflammatory but not basic fibroblast growth factor-dependent neovascularization in the mouse cornea

Lab Invest. 2003 Jul;83(7):927-38. doi: 10.1097/01.lab.0000075642.11787.83.

Abstract

Corneal neovascularization develops in several pathologic conditions, but its underlying mechanisms remain elusive. We used a mouse inflammatory corneal model (corneas cauterized with silver nitrate) and assessed the role of monocyte/macrophage-attracting factors, macrophage chemotactic protein-1 (MCP-1), and a proinflammatory cytokine, IL-1beta, on macrophage recruitment and neovascularization. Both MCP-1, IL-1beta protein, and mRNA levels increased markedly 12 hours after the chemical cauterization. In situ hybridization showed that MCP-1 was located in corneal epithelial cells, and IL-1beta was located in corneal epithelial cells and infiltrating inflammatory cells. In addition, double staining of corneas with antibodies specific for monocytes/macrophages and IL-1beta revealed that IL-1beta was found in infiltrating monocytes/macrophages at Day 2 after cauterization. Both IL-1beta and MCP-1 induced neovascularization in a rat cornea model, and the cauterization-induced corneal neovascularization was partially inhibited by subconjunctival injection of anti-IL-1beta or anti-MCP-1. Coadministration of two antibodies inhibited corneal neovascularization slightly more than that by the administration of each. In contrast, administration of the anti-MCP-1 or anti-IL-1beta showed minimal inhibition of basic fibroblast growth factor-driven corneal neovascularization by mouse cornea assay. Cauterized corneas treated with anti-MCP-1 antibody had significantly fewer monocytes/macrophages than control. These results indicate the existence of distinct monocyte/macrophage-involved angiogenic pathways in mouse cornea, in which MCP-1 released from corneal epithelial cells attracts monocytes/macrophages into the cornea, where they release IL-1beta leading to inflammatory neovascularization. In addition, the IL-1beta and MCP-1 released from the corneal epithelial cells may directly induce corneal neovascularization.

MeSH terms

  • Animals
  • Antibodies, Blocking / pharmacology
  • Cell Movement / drug effects
  • Chemokine CCL4
  • Cornea / blood supply*
  • Cornea / drug effects
  • Cornea / metabolism
  • Cornea / pathology
  • Disease Models, Animal
  • Drug Synergism
  • Epithelium, Corneal / metabolism
  • Epithelium, Corneal / pathology
  • Female
  • Fibroblast Growth Factor 2 / physiology*
  • In Situ Hybridization
  • Interleukin-1 / genetics
  • Interleukin-1 / immunology
  • Interleukin-1 / metabolism*
  • Interleukin-1 / pharmacology
  • Macrophage Inflammatory Proteins / genetics
  • Macrophage Inflammatory Proteins / immunology
  • Macrophage Inflammatory Proteins / metabolism*
  • Macrophage Inflammatory Proteins / pharmacology
  • Macrophages / drug effects
  • Macrophages / physiology
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Neovascularization, Pathologic / metabolism*
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Antibodies, Blocking
  • Chemokine CCL4
  • Interleukin-1
  • Macrophage Inflammatory Proteins
  • RNA, Messenger
  • Fibroblast Growth Factor 2