IMMUNOHISTOCHEMICAL ANALYSIS OF PROLIFERATING CELLS IN A STERILE LABYRINTHITIS ANIMAL-MODEL

Inflammatory reactions within the cochlea lead to the formation of fib rotic tissue and bone. To determine which cells are involved in the pr oliferation of the inflammatory response within the cochlea, sterile l abyrinthitis was created by inoculating keyhole limpet hemocyanin (KLH ) into the scala tympani of systemically sensitized animals. Cellular proliferation was assessed immunohistochemically using the monoclonal antibody Ki-67. Proliferating cells were identified among inflammatory cells and fibroblasts within the matrix, as well as in endosteal cell s lining the scala tympani, Inflammatory and potential osteoprogenitor cells were labeled as late as 6 weeks after inoculation, suggesting t he absence of a strong immunosuppressive mechanism. Endosteal cells ma y proliferate and secrete the extracellular matrix used by the inflamm atory cells to move within the cochlear scalae, They may also particip ate in the ossification of the inflammatory matrix.