Expression of mucins on the mucosal surface of lungs of 4-week-old pigs

The aim of this study was to determine the immunoreactivity of normal small bronchial, bronchiolar, respiratory bronchiolar, and interalveolar epithelium using antibodies to six mucins: MUC1, MUC2, MUC4, MUC5AC, MUC5B, and MUC6. The large, gel-forming secreted mucins MUC2, MUC5AC, and MUC5B were widely expressed in the lower respiratory tract. The results of this study demonstrate that these secreted mucins form a gel to cover and protect the mucosal surface in the lower respiratory tract of pigs.