Development of a functional human bronchial model of mucin secretion

In an attempt to study the functional aspects of respiratory mucin secretion and the effects of mediators of inflammation on the release of M1/MUC5AC mucins in airways diseases, an ex vivo human bronchial model of mucin secretion was developed. Anti-M1 mucin monoclonal antibodies raised against the peptidic core of ovarian cyst M1 mucins were used. PAS and Alcian blue stainings of sections of bronchial rings revealed the presence of mucins in epithelial goblet cells as well as in glandular mucous cells. Immunohistochemical labelling of these sections with anti-M1 monoclonal antibodies revealed a preferential localization of M1/MUC5AC mucins in epithelial goblet cells. Functional studies were performed on this bronchial model using various secretagogues (methacholine, leukotrienes D4 and anti-human immunoglobulin E antibodies). No statistical difference of M1/MUC5AC mucin secretion was observed after a one-hour stimulation of bronchial rings with these agents. The development of an ex vivo functional human bronchial model of mucin secretion and the use of specific anti-M1 antibodies are essential tools in studying the regulation of the M1/MUC5AC mucin release from human airways.