Antigen-specificity of antiretinal antibodies in patients with noninfectious uveitis.

OBJECTIVE: Antiretinal antibodies (ARAs) have previously been described in noninfectious uveitis. However, the antigen specificity of these ARAs has not been investigated. The purpose of this study was to identify antigen-specific ARAs in noninfectious uveitis.

METHODS: A total of 18 patients with noninfectious uveitis were enrolled. Surface plasmon resonance was used to measure binding responses of patient and control sera against several uveitogenic proteins: recoverin, S-antigen, interphotoreceptor retinoid binding (IRBP), retinal-pigment-epithelium-specific 65-kDa protein (RPE65), tyrosinase-related protein 1 (TRYP1), and tyrosinase-related protein 2 (TRYP2).

RESULTS: The frequency of ARA positivity against S-antigen, IRBP, RPE65, TYRP1, and TYRP2 in patients with uveitis did not differ significantly from that of normal controls. However, ARA positivity for recoverin was more frequently observed in patients with uveitis (p = 0.002). A total of 10 patients in the uveitis cohort had birdshot chorioretinopathy, and all 10 were positive for anti-recoverin ARAs.

CONCLUSIONS: Patients with noninfectious uveitis have increased frequency of ARA positivity against recoverin. This ARA deserves further investigations as a potential biomarker and pathogenic agent in noninfectious uveitis, especially in birdshot chorioretinopathy.