A murine model of asbestosis.

Balb/c mice were exposed to aerosolized chrysotile fibers and evaluated as a host for the study of asbestos-induced pulmonary disease. Histologically, an initial macrophage reaction was found to progress to "asbestos body" formation and diffuse focal interstitial fibrosis within 1 year of a chronic exposure period. This reaction was most intense in areas adjacent to respiratory bronchioles and alveolar ducts. Two morphologically distinct tumors at the pulmonary visceral surface were also discovered among a high percentage of asbestos-exposed mice. Bronchoalveolar lavage demonstrated an eventual alteration of the retrievable cell populations among the dusted animals. Evaluation of systemic B-lymphocyte activity suggested a stimulation of this cell subset following chrysotile inhalation. These results demonstrate that subsequent to chronic asbestos exposure, the mouse develops pulmonary and immunologic changes very similar to those noted in human asbestosis.