Mucinous Airway Defects in Mice

Mice were used with Institutional Animal Care and Use Committee approvals. Muc5ac^−/− mice were generated previously^{16 (link)}. Muc5b^−/− and Muc5b^Tg mice were generated here. Muc5b protein was assessed immunohistochemically using rabbit polyclonal antisera. Ciliary beat, MCC, and transport were assessed as described previously. Lung function was measured using a head-out plethysmograph and a flexiVent (Scireq, Montreal, Quebec, Canada), and blood oxygen was assessed using a pulse oximeter. Otitis media was assessed by visual otoscopy and middle ear lavage (MEL). Pulmonary inflammation was assessed by histology and lung lavage. Lavaged leukocytes were identified by light microscopy and flow cytometry. Neutrophils, macrophages, MHC-II, and apoptotic cells, were detected using commercially available Ab’S and reagents. S. aureus was administered by 10 μl intranasal or 50 μl intratracheal inocula at 10⁷-10⁸ CFU/animal. Bacteria and bacterial DNA were isolated from MEL, lung homogenates, and lung lavage pellets. Isolated colonies were phylotyped by 16S rRNA and mecA sequencing. Kaplan-Meier (1f and 3h, l), regression (1e and 2f), one-sided t-test (1g-i, k, l; 2b-e, g; 3b, c, f, g, j, k, and 4c, d, f, g, i, j), and one-way ANOVA (3i and 4a, h, j, l) with appropriate corrections for multiple comparisons, unequal variances, and non-Gaussian distribution were carried out using GraphPad Prism v5.04 (GraphPad Software, Inc., La Jolla, CA). Full methods are found in Supplementary Information.