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Background: A high incidence of autoantibodies to lens proteins has been found in sera of patients with uveitis. We showed previously that the anti-lens antibodies reacted predominantly with α-crystallins. The aim of the present study was to identify immunodominant epitopes within the protein chains of human αA- and αB-crystallin. Methods: Epitope specificities of antibodies to αA- and αB-crystallin were examined by ELISA using synthetic overlapping peptides, spanning the entire length of both α-crystallins. The peptides consisted of 25 amino acid residues, with an overlap of at least eight amino acids each. The synthetic peptides were tested against sera of 110 patients with different uveitis forms, classified according to anatomical location of intraocular inflammation. Results: Four immunodominant regions within the protein chains of αA- and αB-crystallin could be identified. These regions were recognized by antibodies in sera of 56% of uveitis patients. Anti-lens antibodies of IgG-type reacted preferentially with regions located at amino acid (aa) residues aa:69-93 and aa:137-161 of αA-crystallin as well as aa:69-110 and aa:137-161 of αB-crystallin. IgM antibodies recognized predominantly region aa:149-173 of αA-crystallin, and aa:69-110 and aa:151-175 of αB-crystallin. IgM antibodies directed to peptide aa:69-93 of αB-crystallin were found in sera of 30% of patients with intermediate uveitis. Conclusions: Four immunodominant B-cell epitopes within the protein chains of αA- and αB-crystallin have been identified; however, no clear correlation with the anatomically defined uveitis subtypes has been found except for intermediate uveitis. Whether there may be a correlation with uveitis forms with similar etiopathogenesis has to be evaluated in further studies. [ABSTRACT FROM AUTHOR]

Abstract Background  Uveitis is an intraocular inflammatory disease in which autoimmune reactions have been discussed in playing an important role. Many data in this respect derived from the animal model of “experimental autoimmune uveitis”, where several organ-specific autoantigens have been described such as the retinal S-antigen and the interphotoreceptor retinoid-binding protein. However, their diagnostic and pathogenic role in humans has been controversially discussed. In recent studies, the possible relevance of βB1-crystallin, present in lens and ciliary body, has been outlined. We, therefore, wanted to analyse whether sera from patients with uveitis might contain antibodies to lens proteins Methods  Human lenses from cadaveric eyes were shock frozen, homogenized, and resuspended. The resulting suspension (human lens protein fraction - HLPF) was analyzed for antigenicity by ELISA and Western blotting with patients’ sera. A total of 165 patients with uveitis, 54 patients with scleritis and episcleritis, 56 patients with other eye diseases, and 112 healthy blood donors were studied. Results   Twenty-six (49%) of the 53 patients with anterior uveitis, 17 (32%) of the 53 patients with intermediate uveitis and 7 (22%) of 32 patients with posterior uveitis reacted in the ELISA with the HLPF. Antibodies to lens antigens were detected in one-third of patients with panuveitis and retinal vasculitis. In contrast, only 12% of the healthy blood donors were positive in the ELISA. The number of patients with an autoimmune response to α-crystallins in Western blot predominated in all investigated groups. Conclusions  These data indicate that antibodies to lens proteins occur in a high incidence in sera from patients with uveitis. Forty-nine percent of the patients with anterior uveitis and only 12% of healthy controls were positive in the ELISA. In our groups of patients and controls the autoantibodies reacted in the Western blot predominantly with α-crystallin. Further studies are required to analyze in more detail the clinical and etiopathogenetic relevance of the antilens antibodies in uveitis. [ABSTRACT FROM AUTHOR]

· Objective: To describe the clinical and serologic findings of 50 antiphospholipid antibody (APA)-positive patients within a retrospective study. · Methods: Measurement of visual acuity, slit-lamp biomicroscopy, tonometry, fundus examination and perimetry. Laboratory tests were performed for detection of APA against thromboplastin and cardiolipin. Antinuclear antibodies (ANA), antibodies to dsDNA, antithyroidal and antiparietal antibodies were also tested. · Results: A combination of both transient and permanent visual disturbances was noticed in more than half of the patients. Transient visual disturbances included transient blurred vision, partial defects of the visual fields and amaurosis fugax. The most frequent permanent abnormalities were optic atrophy in 20 patients, due to AION in 9 cases, and disturbances of the choroidal circulation in 17 patients. Fourty-six patients had positive levels of thromboplastin APA; cardiolipin APA were found to be increased in 36 patients. · Conclusions: We did not find a clear correlation between APA activity or the immunoglobulin classes in the individual and the severity of the ocular disease. The benefit from a therapy with the antiplatelet agent acetylsalicylic acid was evident in a reduction of the patients’ transient visual disturbances and, in most cases, no further progression of permanent visual field defects was observed. [ABSTRACT FROM AUTHOR]