Abstract
Purpose: :
The role of lens proteins in the pathogenesis of intraocular inflammation is not completely understood. Recently ßB1–crystallin has been identified as a candidate autoantigen in uveitis. The purpose of our study was to analyze sera from patients with uveitis for antilens antibodies.
Methods: :
A suspension from shock frozen homogenized human lens was analyzed for antigenicity by ELISA and Western blotting. Sera from 165 patients with uveitis, 55 patients with scleritis and episcleritis, 56 patients with other eye diseases (such as Ischemic optic neuropathy, blepharitis, and keratitis) and 112 healthy blood donors were tested.
Results: :
Antibodies to lens proteins were detected by ELISA in approximately 50% of patients with anterior uveitis, 32% of patients with intermediate uveitis and 22% of patients with posterior uveitis. Also one third of patients with panuveitis (30%) and retinal vasculitis (35%) as well as 25% of patients with scleritis and episcleritis were positive. In contrast, the incidence of these antibodies was only 11% in patients with other eye diseases resembling that in normal individuals (12%). In order to identify the target antigen(s) of these anti–lens antibodies, ELISA positive sera were also tested by Western blotting against lens proteins. Patients’ sera reacted predominantly with α–crystallins (anterior uveitis 71%, intermediate uveitis 67%, and posterior uveitis 80%). Antibodies to ß–crystallins were observed only in a small number of patients.
Conclusions: :
The data indicate that antibodies to lens crystallins are detectable in high incidence in sera from uveitis patients. Lens antibodies were detected more frequently in anterior uveitis than in any other type of intraocular inflammation. In the investigated patients’ groups the autoantibodies reacted in Western blot predominantly with α–crystallins. To our knowledge this is the first report of an elevated autoimmune response to α–crystallins in uveitis patients.
Keywords: autoimmune disease • uvea • crystalline lens