α-Crystallins and vascular endothelial growth factor in aqueous humor of patients with neovascular age-related macular degeneration

Purpose: This study investigated aqueous humor (AH) levels of α-crystallins and vascular endothelial growth factor (VEGF) in patients with neovascular age-related macular degeneration (nAMD). Study design: Prospective study. Methods: AH samples were collected from treatment-naïve phakic nAMD patients before the first and third anti-VEGF injections and from cataract patients without retinal disease as controls. αB-crystallin, αA-crystallin, and VEGF levels were quantified using enzyme-linked immunosorbent assay. Patients were classified as good responders (achieved remission) or poor responders (persistent intraretinal or subretinal fluid) according to response after three consecutive monthly anti-VEGF injections. Results: A total of 28 eyes from 24 nAMD patients and 27 eyes from 23 controls were analyzed. nAMD showed higher αB-crystallin and VEGF, but similar αA-crystallin levels versus controls (P < 0.001, P = 0.002, and P = 0.721, respectively). In nAMD eyes, after two anti-VEGF injections, αB-crystallin and αA-crystallin remained unchanged, whereas VEGF decreased (P = 0.057, P = 0.182, and P = 0.017, respectively). Among nAMD eyes, 20 eyes from 18 patients were good responders and 8 from 6 were poor responders. Good responders demonstrated reductions in αB-crystallin and VEGF (P = 0.016 and P = 0.002, respectively), whereas poor responders showed no significant changes (P = 0.249 and P = 0.075, respectively). In untreated nAMD eyes, αB-crystallin and VEGF levels showed a positive correlation (P = 0.010). Conclusion: In nAMD, AH αB-crystallin levels were elevated compared with controls. Among good responders to anti-VEGF therapy, αB-crystallin levels decreased. Moreover, αB-crystallin levels showed a positive correlation with VEGF.