| First Author | Portillo JA | Year | 2014 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 55 |
| Issue | 12 | Pages | 8590-7 |
| PubMed ID | 25477319 | Mgi Jnum | J:230280 |
| Mgi Id | MGI:5755916 | Doi | 10.1167/iovs.14-15340 |
| Citation | Portillo JA, et al. (2014) Proinflammatory responses induced by CD40 in retinal endothelial and Muller cells are inhibited by blocking CD40-Traf2,3 or CD40-Traf6 signaling. Invest Ophthalmol Vis Sci 55(12):8590-7 |
| abstractText | PURPOSE: The cell surface receptor CD40 is required for the development of retinopathies induced by diabetes and ischemia/reperfusion. The purpose of this study was to identify signaling pathways by which CD40 triggers proinflammatory responses in retinal cells, since this may lead to pharmacologic targeting of these pathways as novel therapy against retinopathies. METHODS: Retinal endothelial and Muller cells were transduced with vectors that encode wild-type CD40 or CD40 with mutations in sites that recruit TNF receptor associated factors (TRAF): TRAF2,3 (DeltaT2,3), TRAF6 (DeltaT6), or TRAF2,3 plus TRAF6 (DeltaT2,3,6). Cells also were incubated with CD40-TRAF2,3 or CD40-TRAF6 blocking peptides. We assessed intercellular adhesion molecule-1 (ICAM-1), CD40, monocyte chemoattractant protein-1 (MCP-1), VEGF, and prostaglandin E(2) (PGE(2)) by fluorescence-activated cell sorting (FACS), ELISA, or mass spectrometry. Mice (B6 and CD40(-/-)) were made diabetic using streptozotocin. The MCP-1 mRNA was assessed by real-time PCR. RESULTS: The CD40-mediated ICAM-1 upregulation in endothelial and Muller cells was markedly inhibited by expression of CD40 DeltaT2,3 or CD40 DeltaT6. The CD40 was required for MCP-1 mRNA upregulation in the retina of diabetic mice. The CD40 stimulation of endothelial and Muller cells enhanced MCP-1 production that was markedly diminished by CD40 DeltaT2,3 or CD40 DeltaT6. Similar results were obtained in cells incubated with CD40-TRAF2,3 or CD40-TRAF6 blocking peptides. The CD40 ligation upregulated PGE(2) and VEGF production by Muller cells, that was inhibited by CD40 DeltaT2,3 or CD40 DeltaT6. All cellular responses tested were obliterated by expression of CD40 DeltaT2,3,6. CONCLUSIONS: Blockade of a single CD40-TRAF pathway was sufficient to impair ICAM-1, MCP-1, PGE(2), and VEGF upregulation in retinal endothelial and/or Muller cells. Blockade of CD40-TRAF signaling may control retinopathies. |
