Tracheo-bronchial mucin gene expression as detected by in situ hybridization.

To understand regulation of the tracheo-bronchial mucin (TBM) gene expression we developed cDNA probes encoding TBM. We also raised antisera against mucin protein (deglycosylated and glycosylated), and developed immortalized tracheal epithelial cells which express mucin (at the RNA and protein level). TBM cDNA probes can detect TBM mRNA in situ in samples from dog and human primary tracheal epithelial cells and cell lines derived from them. For clinical application, conditions were optimized for detection of the TBM mRNA in human turbinal and nasal polyps and trachea of cystic fibrosis (CF) and non-CF subjects. Fixing and hybridization conditions were found to be critical for the optimum hybridization signal. Riboprobes proved to be better than cDNA or oligonucleotide probes. The application of these newly developed molecular tools in the genetic therapy of CF is discussed herein.