The role of the endolymphatic sac in inner ear immunity.

The present study further assessed the role of the endolymphatic sac (E.S.) in the generation of inner ear immune responses. Guinea pigs underwent unilateral endolymphatic sac obliteration (Rt) and the opposite ears (Lt) served as controls. The animals were then systemically sensitized to KLH and both inner ears were subsequently challenged with KLH. Absence of the E.S. significantly reduced perilymph anti-KLH levels and greatly reduced cellular infiltration within the cochlea as compared to the control ears (Lt). Control studies demonstrated that neither surgical trauma to the semicircular canal nor the chemical effects of silver nitrate caused immunosuppression of the normal inner ear immune response. From these findings, the E.S. appears to be the main site of antigen processing in the inner ear and a site analogous to the gut with respect to absorptive and immunologic functions.