Ptok M, Nair T, Carey T E, Altschuler R A
HNO-Hearing Research Laboratories, Department of Otolaryngology, University of Tübingen, FRG.
Hear Res. 1993 Apr;66(2):245-52. doi: 10.1016/0378-5955(93)90144-p.
Murine monoclonal antibodies against cochlear structures were previously generated to obtain probes for elucidating the function of cochlear cell subsets. Preliminary immunocytochemical characterization showed that the monoclonal antibody KHRI 3 binds to supporting cells but not sensory cells in the guinea pig cochlea. We have now investigated KHRI 3 epitopes in other species and other parts of the inner ear. The KHRI 3 epitope appears to be species-specific since no immunolabeling was seen in rat inner ear nor in chick inner ear. In immunocytochemical assays in the guinea pig vestibular tissues KHRI 3 stained saccular wall cells and transitional epithelial cells in the utricle and ampules as well as clusters of cells in the endolymphatic sac. In Western blots KHRI 3 stained a broad 70-75 kDa band in lanes loaded with guinea pig cochlea homogenates--as seen previously--as well as in lanes loaded with vestibular tissue homogenates. The immunolabeling patterns suggest that KHRI 3 epitopes are cell membrane components or related to membrane structures. Thus the monoclonal antibody KHRI 3 appears to define a nonsensory cell subset in the guinea pig inner ear that can be identified by expression of KHRI 3 epitopes.
