Inner ear-specific autoantibodies.

The sera of patients with idiopathic sensorineural hearing loss (SNHL) were examined, using qualitative immunoblotting (Western blotting), for the presence of inner ear (IE)-specific autoantibodies. The water-soluble extracts and the sodium dodecyl sulfate-soluble extracts were prepared as the antigens from bovine IE tissues and several other organs in order to determine the specificity of autoantibodies in their sera to the IE. Some patients (n = 46) tested had autoantibodies that reacted with 68-, 62-, 55-, 50-, or 47-kd antigenic determinants found in all tissues, while others (n = 13) showed IE-specific autoantibodies which reacted with 220-, 60-, 58-, 33-35-, or 32-kd determinants. The presence of these autoantibodies from patients with progressive SNHL may have important implications with regard to their etiology and possibly their sensitivity to therapeutic intervention. It is now necessary to purify these IE-specific antigens and determine their clinical usefulness.