title: Culture and characterization of rat middle-ear epithelium.
abstract: This study was performed to design a method for the culture of rat middle-ear epithelium and to apply the method to investigate the characteristics of this epithelium. Culture of explants of middle-ear epithelium in the presence of the epidermal growth factor was successful, whereas serial cultivation required 3T3 feeder cells in addition to the epidermal growth factor. Cultured middle-ear epithelium was studied by phase-contrast microscopy, transmission and scanning electron microscopy, and combined light and scanning electron microscopy (LM/SEM). These techniques showed similarity between the cultured and the natural middle-ear epithelium. Explants and outgrowths showed both flat polygonal and ciliated epithelial cells. In serial cultivation, however, only the first of these cell types was observed. Frequently, a single primary cilium was found on the cell surface. Transmission electron microscopy showed cross-linked envelopes whose formation was promoted by ionophore X537A. Cytokeratin was demonstrated by immunoblotting, immunofluorescence, and immunoperoxidase methods, using an anti-cytokeratin monoclonal antibody. The model described here permits study of the differentiation of middle-ear epithelium in vitro and may be of future value for the study of chronic middle-ear diseases.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure; D002478:Cells, Cultured; D004432:Ear, Middle / Q000648:ultrastructure*; D004847:Epithelial Cells; D004848:Epithelium / Q000648:ultrastructure; D007633:Keratins / Q000032:analysis; D008297:Male; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008858:Microscopy, Phase-Contrast; D008871:Microvilli / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D013194:Staining and Labeling
chemical_list: D007633:Keratins