[Intercellular interactions in morphogenesis of initial lesions and sclerosis in interstitial lung diseases]

A total of 117 patients with pulmonary interstitial diseases (PID) were examined. The functional activity of alveolar macrophages was assayed in the lavage fluid and in lung tissue biopsy specimens from the generation of active oxygen forms, the secretion of tumor necrosis factor, fibronectin, expression of c-fos- and c-sis-oncoprotein. The stereotypic value for various PID was the development of alveolitis running in 2 stages: 1) early one, including exudative inflammation and 2) late one, involving sclerotic changes up to the formation of the honeycomb lung. This results in the block of the blood-air barrier and progression of respiratory failure and hypoxia in patients. The morphogenesis of fibrosing alveolitis is formed of alveolar septal damages caused by etiological agents of various nature, which is frequently unclear, by active forms of oxygen, lipid peroxidation products, proteases, tumor necrosis factor, which are produced by activated alveolar macrophages and polymorphonuclear leukocytes. The alveolar macrophage that secretes growth factors, c-fos- and c-sis-oncoproteins plays the key role in the progression of sclerotic changes. Lung cancer may develop at the end of fibrosing alveolitis at the stage of the honeycomb lung.