Antibodies against Inner-Ear Proteins in the Sera of Patients with Inner-Ear Diseases

Abstract

Sera from patients with various inner-ear diseases, especially Ménière’s disease, were investigated by Western blot against guinea pig inner-ear proteins. Of 45 patients, 24 (53%) with various inner-ear diseases had antibodies against inner-ear proteins, compared with 0 of 10 (0%) in control subjects without inner-ear diseases. Of the 10 proteins that showed a positive reaction with patient sera, the 28-kD band was unique in that it appeared only in the membranous fraction of the inner ear and was highly positive (28%) in reaction with Ménière’s disease patient sera. The results in the present study with proteins extracted from guinea pig inner ear were consistent with our previous study using proteins from human inner ear, suggesting that the 28-kD protein may be a candidate for detecting autoimmune inner-ear disease.

Autoantibodies against inner ear proteins in patients with delayed endolymphatic hydrops and unilateral juvenile deafness

“…Sera obtained from their DEH patients reacted against a 68-or 35 Á/36-kDa antigen, while such a response was seen in only 3/43 normal controls. In the present study, we found that 6/8 patients had antibodies against rat inner ear proteins, a finding consistent with our previous report [8]. However, the inner ear proteins targeted by antibodies in the present patients' sera were quite different from those described in the report of Harris and Aframian [10].…”

“…However, the results of these investigations, which include our own [8], are not in agreement. Damage to the inner ear causing profound hearing loss exposes the immune system to previously sequestered inner ear proteins, which may result in the production of antibodies against the inner ear.…”

“…Three out of 9 DEH patients showed seropositivity against the 28-kDa protein. In our previous study [8], we found that the 28-kDa protein from guinea pig inner ear was the protein most frequently reactive in MD. As approximately half of patients with autoimmune inner ear disease display endolymphatic hydrops [13], the contralateral type of DEH, as well as MD, appear to involve autoimmune mechanisms most often mediated by the antibody against the 28-kDa protein.…”

“…One main reason for this uncertainty is that the inner ear antigens targeted by the immune system have not yet been identified. In a previous study [8] we found various autoantibodies against guinea pig inner ear proteins in sera from patients with Ménière's disease (MD). Those sera frequently reacted with inner ear proteins with molecular weights of 28, 52 or 67 kDa.…”

“…The contralateral type of DEH is believed to have an autoimmune etiology, and sometimes develops from unilateral juvenile deafness [10]. To determine whether the autoantibodies detected in our previous study [8] were involved in the etiology of DEH, we performed Western blotting using sera from patients with DEH, others with profound unilateral juvenile hearing loss and normal controls.…”