title: Identification of an anti-aldolase autoantibody as a diagnostic marker for diabetic retinopathy by immunoproteomic analysis.
abstract: Circulating autoantibodies specific for retinal proteins are associated with retinal destruction in patients with diabetic retinopathy (DR). In this study, we screened diabetic sera for the presence of anti-retinal autoantibodies with an aim of developing diagnostic markers for DR. Immunoblot analysis of DR patients' sera with human retinal cytosolic proteins revealed a higher incidence of anti-retinal autoantibodies, compared to normal blood donors or diabetic patients without DR. Anti-retinal protein autoantibody profiles of DR patient sera were obtained by 2-DE immunoblot analysis. Specifically, 20 protein spots reactive with DR patient sera were identified by ESI-MS/MS. Of these spots, 14 were specific for DR patients, and 4 reacted with both non-proliferative DR (non-PDR) and PDR sera. The anti-aldolase autoantibody was selected as a DR marker candidate, and specific reactivity of DR patient sera was confirmed by immunoblot analysis with rabbit aldolase. The serum anti-aldolase autoantibody level was measured by ELISA. DR patients showed significantly higher autoantibody levels than normal donors or diabetic patients without retinopathy. However, no significant differences were observed between non-PDR and PDR patients, suggesting that the level of anti-aldolase autoantibody is not determined by the severity of retinopathy in diabetic patients. Our data collectively demonstrate that the anti-aldolase autoantibody serves as a useful marker for DR diagnosis.
authors.affiliation: Department of Bioscience and Biotechnology, Institute of Bioscience, Sejong University, Kwangjin-gu, Seoul, Korea.
authors.forename: Bo-Young
authors.initials: BY
authors.lastname: Ahn
authors.forename: Eun-Sun
authors.initials: ES
authors.lastname: Song
authors.forename: Yang Je
authors.initials: YJ
authors.lastname: Cho
authors.forename: Oh Woong
authors.initials: OW
authors.lastname: Kwon
authors.forename: Jin Kook
authors.initials: JK
authors.lastname: Kim
authors.forename: Na Gyong
authors.initials: NG
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000378:metabolism*; D003600:Cytosol / Q000276:immunology / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005634:Fructose-Bisphosphate Aldolase / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D012160:Retina / Q000276:immunology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D020543:Proteome; D005634:Fructose-Bisphosphate Aldolase