Abstract
Purpose :
Interleukin (IL)-17A has been previously reported to play a role in age-related macular degeneration, glaucoma, and diabetic retinopathy. Although retinal neovascularization can lead to vision loss in all of these ocular diseases, the role of IL-17A in retinal vascular angiogenesis and neovascularization is unclear. In other diseases, IL-17A enhances angiogenesis. Hence, we hypothesized that IL-17A enhances retinal vascular angiogenesis and neovascularization.
Methods :
Human Muller glia and retinal endothelial cells (100,000 cells/well) were unstimulated or stimulated with 20ng/ml of recombinant IL-17A for 16h, and levels of VEGFA was quantified in the supernatants (n=6/group) by ELISA. Further, angiogenesis was examined in 10,000 unstimulated or IL-17A stimulated (20ng/ml) human retinal endothelial cells (hREC) using WimTube software. Additionally, cellular proliferation was examined in unstimulated, IL-17A, VEGFA, or IL-17A+VEGFA (20ng/ml of each) stimulated hREC by BrdU analysis. Finally, retinal neovascularization was examined in vivo using the oxygen induced retinopathy model in wild-type C57BL/6 and IL17A-/- mice (n=5/group). Briefly, 7-day-old mice were placed into a 75% oxygen chamber for 5 days, then placed into normal room air for 5 days, prior to analysis of 17-day old mice. Retinas were collected from euthanized mice and neovascularization of isolectin stained whole mounts was quantified.
Results :
When human Muller glia and retinal endothelial cells were incubated with 20ng/ml of recombinant IL-17A, VEGFA production was induced. This same concentration of recombinant IL-17A also induced retinal endothelial cell angiogenesis per WimTube and BrdU analysis. Additionally, VEGF-induced proliferation in human retinal endothelial cells was significantly increased (p<0.05) when IL-17A was added. Finally, there was a significant decrease in neovascularization of IL17A-/- than wild-type C57BL/6 mice when retinal vascular proliferation was induced using the oxygen induced retinopathy model.
Conclusions :
These results support our hypothesis that IL-17A enhances retinal vascular angiogenesis and neovascularization. Further in vivo studies of ocular disease specific neovascularization will be needed to define the role of IL-17A in neovascular glaucoma and proliferative diabetic retinopathy.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.