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Objective: This study aimed to present further evidence of specific antibodies reactive against bovine inner ear proteins found in patients with Meniere's disease., Background: There are a growing number of experimental and clinical features of Meniere's disease that indicate an immune association. Circulating antibodies directed against inner ear proteins have been detected in patients with bilateral progressive hearing loss and Meniere's disease., Methods: A total of 36 patients with classical Meniere's disease were studied noting the presence of active or inactive, bilateral or unilateral disease. Bovine membranous labyrinth was used as inner ear extract and separated to molecular weights using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Western blotting included the addition of serum buffer (casein, Tween, and bovine serum albumins) and the use of alkaline phosphatase labeled anti-human immunoglobulin antibodies., Results: The findings represent strong evidence of antibodies reactive to inner ear proteins. The incidence of these antibodies was correlated significantly with disease activity., Conclusions: The findings are further evidence of an immune process that is involved in Meniere's disease.

Immune inner ear disease is a relatively new and distinct clinical entity that produces unexplained, rapidly progressive, bilateral sensorineural hearing loss. The diagnosis is based on clinical manifestations, positive immune laboratory testing, and beneficial response to a trial of corticosteroids. Immune laboratory tests are used to confirm a presumptive clinical diagnosis. The two tests most commonly used are the lymphocyte transformation test and Western blot immune assay. The rationale behind these tests is presented, and the role they play in laboratory diagnosis of immune inner ear disease is discussed.

Recently, it has been suggested that otosclerosis represents the host's ongoing immunologic response to measles or other viral antigens. Documentation of past inflammation within the inner ear would serve as further evidence that this mechanism may be at play in the pathogenesis of the disease. Among the characteristic signs of prior inflammation in the inner ear is the presence of lamellar bone at the site of inflammation. This has been described in the temporal bone of a patient with immune-mediated deafness and with the temporal bones of experimental models of immune-mediated inner ear disease. Review of temporal bones with round window otosclerosis from the Eastern Temporal Bone Bank at the Massachusetts Eye and Ear Infirmary show that in four of ten cases there are characteristic signs of a prior severe inflammatory event centered in the scala tympani adjacent to the otosclerotic lesion. Otosclerosis, therefore, may have an inflammatory stage that is the consequence of a host response to an inciting event.

Recent clinical studies, experimental research, and various testing techniques in otoimmunology have resulted in presentation of the synonymous terms autoimmune sensorineural hearing loss, autoimmune inner ear disease, immune-mediated sensorineural hearing loss, and immune-mediated inner ear disease or disorder. The development of this terminology and the clinical presentation of this disease as well as whether it is really a distinct clinical entity are discussed. Laboratory tests for immune-mediated inner ear disease are presented along with a discussion of progress being made in the growing field of otoimmunology.

Cellular and humoral immune reactions may play a role in the ethiopathogenesis of an audiovestibular dysfunction. Immune-mediated inner ear disorders can be of cochlear and retrocochlear origin. Autoimmunity plays occasionally a role, but is certainly not obligatory.

Tissue nonspecific antibodies may give an idea about the etiopathogenesis of the inner ear disease. They are of some prognostic and therapeutic value. They are routinely tested in most inner ear patients. On the other hand, inner ear specific autoantibodies do exist. Their diagnostic, prognostic and therapeutic significance are still unclear. Cellular immunity is tested only in selected cases based upon the clinical picture and the results of humoral immunity testing. It needs whole fresh blood as well as facilities not available in all laboratories. Their main role seems to be in providing solid basis for cortisone therapy justification. Our therapeutic concept proved to be promising in some cases. Immune-mediated inner ear disorders do not form a separate clinical entity. We would rather add immune mediation to the different causes postulated for the various inner ear disorders, as a plausible explanation for a certain percentage of the group categorized as idiopathic of unknown etiology.