The effect of cortisone acetate on pulmonary lesions in a rabbit model of hypersensitivity pneumonitis (cortisone and hypersensitivity pneumonitis).

Rabbits were sensitized with Micropolyspora faeni by intratracheal inoculations and later challenged with the same antigen either with or without parenteral administration of cortisone acetate prior to challenge. Animals developed anti-M. faeni serum precipitins, M. faeni-induced alveolar macrophage migration inhibition, and positive 48-hr skin reactivity to M. faeni. Sensitized animals also demonstrated an augmented pulmonary histopathological response following respiratory challenge with M. faeni when compared to non-sensitized controls. Cortisone acetate abrogated this augmented pulmonary histopathological response following challenge with M. faeni. Cortisone acetate also abolished the positive alveolar macrophage migration inhibition found in sensitized animals.