Experimental Hypersensitivity Pneumonitis1,2

Abstract

The pulmonary lesions of a hypersensitivity reaction were produced in rats by intravenous and intratracheal injection of anti-rat-lung serum. Because anti-rat-lung-elastin serum produced a similar change, it is speculated that elastin may be one of the major antigenic components of the lung tissue responsible for these lesions. Although many animals died of acute pulmonary edema, some of the animals surviving the acute phase of the reaction developed interstitial pneumonitis and focal arteritis. Pretreatment with cortico-steroids or heparin failed to block the reaction induced by the anti-serum. However, animals kept on a protein-deficient diet showed no significant reaction to the anti-rat-lung-elastin serum injected intravenously. Intravenous injection of anti-rat-collagen serum failed to produce any pulmonary lesion.