As mucociliary clearance is an important innate defense mechanism of the lung, and retention of inhaled irritants and pathogens leads to repeated micro-injury and chronic inflammation, our data support mucociliary dysfunction as an important disease mechanism triggering ILD in both congenital and adult conditional Nedd4-2−/− mice [9,32,34,35]. The gene discussed is NEDD4; the disease is interstitial lung disease.