Regeneration of bronchial epithelium on chronic inflammatory changes under laser treatment.

Investigation of structural and metabolic changes in 188 biopsy specimens from the epithelium of large bronchi of 76 patients with chronic lung disease was carried out. It was shown that endobronchial treatment by helium-neon laser irradiation induced the proliferative and metabolic processes in damaged epithelium, which after getting through the series of transitional forms restores its normal structure and differentiation into ciliated and goblet cells of a normal ultrastructure. The hyperemia, intensive diapedesis of leucocytes, the formation of leucocytic infiltrations and granulations develop in the lamina propria of the bronchial mucosa. Proliferative and metabolic activity of the endotheliocytes and stromal cells increases. Finally, delicate-fibrous connective tissue forms. The simultaneous reorganizations of the epithelium and underlying connective tissue is interpreted from the point of view of the concept of parenchymal-stromal interactions.