Immune response and immunopathology of the inner ear: an update

Abstract

Immune-mediated inner-ear disease includes clinical conditions associated with unilateral or bilateral rapidly progressive forms of sensorineural hearing loss. A systemic autoimmune disorder can be present in less than one-third of cases. Because of the lack of well defined detection methods to identify immune-mediated processes within the inner ear, and the fact that the human inner ear is not amenable to diagnostic biopsy, there has been great interest in developing animal models. Experimental models of sterile and virus-induced labyrinthitis support the participation of the immune system in the aetiopathogenesis of inner-ear disorders: interleukin-2 emanates from the endolymphatic sac and assists in changing the spiral modiolar vein, as in the expression of intercellular adhesion molecule 1, which allows the egress of immune cells from the circulation. The formation of a fibro-osseous matrix ultimately results in degeneration of the inner ear. These investigations have allowed us to alter the immune response for the purpose of regulating its intensity and the subsequent damage to patients.