Immune response and immunopathology of the inner ear: an update

Immune-mediated inner-ear disease includes clinical conditions associated w ith unilateral or bilateral rapidly progressive forms of sensorineural hear ing loss. A systemic autoimmune disorder can be present in less than one-th ird of cases. Because of the lack of well defined detection methods to identify immune-me diated processes within the inner ear, and the fact that the human inner ea r is not amenable to diagnostic biopsy, there has been great interest in de veloping animal models. Experimental models of sterile and virus-induced la byrinthitis support the participation of the immune system in the aetiopath ogenesis of inner-ear disorders: interleukin-2 emanates from the endolympha tic sac and assists in changing the spiral modiolar vein, as in the express ion of intercellular adhesion molecule 1, which allows the egress of immune cells from the circulation. The formation of a fibro-osseous matrix ultima tely results in degeneration of the inner ear. These investigations have allowed us to alter the immune response for the p urpose of regulating its intensity and the subsequent damage to patients.