Abstract
Purpose :
Angiogenesis and subretinal fibrosis are key causes of vision loss in neovascular age-related macular degeneration (nAMD). Despite effective therapy for angiogenesis, fibrosis remains an unmet need. This project evaluates whether inhibiting the co-factor of toll-like receptors, CD14, reduces angiogenesis and/or fibrosis in two mouse models of nAMD.
Methods :
C57Bl6 mice were treated intravitreally with 1ul aliquot of an anti-CD14 antibody, vehicle (phosphate buffer saline) or aflibercept immediately after laser induced choroidal neovascularization (4 spots, 532nm laser, 350mW, 70ms pulse; Micron III Phoenix Systems). Following 7 days, fluorescein angiography was performed and eyes collected for quantitative PCR or fixed for staining with Masson’s trichrome stain (N=10 per treatment per outcome). The Vldlr-/- mouse model of AMD was evaluated to further assess the effects of anti-CD14 treatment on inner retinal angiogenesis. For these experiments, postnatal day 18 mice received a 1ul injection of anti-CD14 or vehicle and tissue collected at postnatal day 30 (n=10 mice per treatment per outcome). Vascular tuft density was quantified from immunolabeled retinal wholemounts and quantitative PCR performed to determine changes in expression of a range of genes including Fgf2, Col1a1, and Ctgf.
Results :
Laser induced lesion size was significantly reduced in eyes receiving anti-CD14 or aflibercept compared to vehicle (~30% reduction; One way ANOVA, p<0.05). In addition, the height of trichrome positive lesions, a measure of fibrosis, was also significantly reduced in anti-CD14 treated eyes but not those that received aflibercept (One Way ANOVA, posthoc Tukeys test p<0.01). Evaluation of anti-CD14 treatment in Vldlr-/- mice revealed it to reduce vascular tuft density compared to vehicle suggesting an effect on angiogenesis. In addition, dysregulation in the expression of Fgf2, Col1a1 and Ctgf was reduced by treatment with anti-CD14.
Conclusions :
Targeting CD14, a co-factor for toll-like receptor function, can reduce both angiogenesis and fibrosis in multiple mouse models of nAMD. Inhibiting CD-14 may reduce vision threatening sequalae in nAMD by reducing both angiogenesis and fibrosis.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.