LYZ and chronic bronchitis: The mechanism of chronic bronchitis development is known to be based on damage to various parts of the local bronchopulmonary defense system: mucociliary clearance, local cellular and humoral immunity (the drainage function of the bronchi is disrupted; the activity of a1-antitrypsin decreases; the production of interferon, lysozyme, IgA, pulmonary surfactant decreases; the phagocytic activity of alveolar macrophages and neutrophils is inhibited).