Associations of plasma-soluble Fas ligand with aging and age-related macular degeneration

PURPOSE. To evaluate the associations between plasma-soluble Fas ligand (sFasL) and age-related macular degeneration (AMD). METHODS. Plasma samples were obtained from 230 individuals (age range, 45-85), with or without AMD. The concentrations of sFasL were determined by an enzyme-linked immunosorbent assay (ELISA). The measured sFasL levels were transformed into cubic roots and were fitted into linear regression models against AMD status, with adjustment for age and sex. RESULTS. Plasma sFasL increased with age and AMD. There was a linear correlation between age and the cubic roots of sFasL. The plasma sFasL concentrations in non-AMD subjects ranged from 0 to 1.63 ng/mL (median, 0.69 ng/mL), whereas in patients with AMD, sFasL ranged from 0 to 2.43 ng/mL (median, 0.18 ng/mL). Between the ages of 61 and 84, the subjects with AMD had significantly higher sFasL than did the non-AMD subjects. There was a sexual dimorphism of the plasma sFasL levels. In non-AMD subjects, sFasL was lower in the females. In patients with AMD, sFasL was higher in the females. CONCLUSIONS. An elevation of plasma sFasL with aging may play a role in the development of AMD and is a potential peripheral marker for monitoring disease progression.