[Immunological reactions of the bronchial mucosa in the morphogenesis of chronic bronchitis].

Local immunity was studied using biopsy specimens obtained during bronchoscopy in 93 patients with various forms of chronic bronchitis. Reduced IgA synthesis and increased IgG synthesis by plasma cells of the lamina propria of bronchial mucosa were demonstrated, and the augmented IgG production along with penetration of various antigens into the lamina propria were shown to be responsible for a local immune-complex reaction involving the microcirculatory bed and resulting in perivascular sclerosis. The damaging and sclerosing processes that repeatedly occur in bronchial mucosa disrupt the epithelial-stromal linkages and interfere with the differentiation of surface epithelium. It is suggested that immunopathologic reactions are implicated in the setting up of a vicious circle which underlies the morphogenesis of chronic bronchitis.