The relationship between antigen levels and middle ear inflammation in antigen-induced otitis media in the chinchilla.

The relationship between antigen levels in middle ear effusions (MEE) and the degree of middle ear inflammation was studied in an antigen-induced otitis media model, using chinchillas sensitized with human serum albumin (HSA). The degree of middle ear inflammation was evaluated by both tympanometric analysis, and cytological and biochemical analyses of the MEE. Middle ear inflammation develops after HSA challenge with a remarkable decrease in HSA levels in the MEE. This inflammation persists even when HSA levels are no longer detectable in the MEE. These findings show that local challenges with an antigen induce a certain degree of middle ear inflammation, which continues even after complete elimination of the antigen from the middle ear through an immunological defense mechanism.