title: Purification of retinal S-antigen by ion-exchange chromatography and chromatofocusing.
abstract: A simple method for the isolation of bovine retinal S-antigen by ion-exchange chromatography on DEAE Sephadex, alone or in combination with a chromatafocusing step is described. High yields of highly purified S-antigen were obtained. Analytical studies indicated that the isolated protein was a single chain, 55 000 Mr glycoprotein with little tendency to self-association and a pI of 5.5. S-antigen prepared in the absence of protease inhibitors migrated on SDS-PAGE as a doublet but close similarity between both protein bands was observed by analysis of papain digests, suggesting that the protein was readily susceptible to proteolysis. S-antigen prepared by this method induces a selectively posterior focal uveoretinitis in a dose-dependent manner.
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology / Q000302:isolation & purification*; D019393:Arrestin; D002417:Cattle; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D005136:Eye Proteins / Q000302:isolation & purification*; D006168:Guinea Pigs; D007122:Immunoelectrophoresis; D008970:Molecular Weight; D012160:Retina / Q000032:analysis*; D014605:Uveitis / Q000276:immunology
chemical_list: D000941:Antigens; D019393:Arrestin; D005136:Eye Proteins