Morphogenesis and pathogenesis of chronic lung diseases. XIII. Experimental investigation of pulmonary chronic suppurations.

The main morphogenetic and pathogenetic elements of pulmonary chronic suppurations were experimentally investigated in rabbits. The animals were sensitized by blood way with complete Freund adjuvant containing serum proteins, which determined a nodular and diffuse granulomatous reaction in the pulmonary tissue. The perturbing agent of the model system was a maintained immediate type hypersensitivity reaction produced by an excess of intrapulmonary antigen accumulation after an intratracheal injection of the same agent with antigens in excess. The animals sacrificed 15, 30 and 45 days after the intratracheal challenge presented a wide and progressive cellulofibrous restructuring of the lung tissue with exclusion of lung areas, persistence of granulocytic foci, release of lactic-dehydrogenase, chronic vascular lesions and diffuse fibrosclerosis. The importance of the persisting antigens which maintain the Arthus type hypersensitivity reaction, of vascular chronic lesions determined by the blood transport of deleterious products and by immunopathologic phenomena, as well as of the cellulo-fibrous proliferation, are emphasized as elements of autoaggressive processes with common and immune components, all contributing to the chronic evolution of pulmonary suppurations.