Abstract
Purpose :
Since the detection of complement components in drusen and the association of genes of the complement system with age-related macular degeneration (AMD), a dysregulated immune response in the pathogenesis of AMD is undisputed. Locally elevated complement activation products in aqueous humor have been already detected in patients with exudative AMD. The aim of this study was to investigate inflammatory mediators and complement factors in non-exudative AMD compared to age correlated controls in anterior chamber fluid.
Methods :
Anterior chamber samples from non-exudative AMD patients and healthy control subjects were examined in a multicenter study. The anterior chamber fluid was collected during routine cataract surgery in each case. Patients with a disease with altered systemic complement system activation or taking immunosuppressive drugs were excluded from the study. Subsequently, the secretion of 13 complement factors and 65 cytokines of each sample was determined by multiplex ELISA.
Results :
Samples from 13 patients with non-exudative AMD and 22 healthy control subjects were examined. Patients with non-exudative AMD did not show significantly increased cytokine or complement protein concentrations in the anterior chamber fluid compared with the control group. Men showed a significantly higher concentration of complement factor I (mean men 13083 MFI ± 9130, mean women 7275 MFI ± 5341; p=0.0419). Smokers showed significantly increased concentrations of CCL-7 (p=0.0062), IL-6 (p=0.0186) and IL-7 (p=0.005). Interestingly, patients between 50 and 60 years of age showed significantly lower concentrations of VEGF-A (mean 117.9 MFI ± 35.76) than aqueous humor samples of patients between 60 and 70 years of age (mean 306.5 MFI ± 88.63) (p=0.0255).
Conclusions :
Non-exudative AMD does not appear to be associated with increased levels of inflammatory mediators or complement factors in the anterior chamber aqueous humor, according to initial results. Phenotypic stratification of the cohort and a correlation of individual cytokine and complement factor concentrations in relation to AMD progression is the subject of current research.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.