Assessment of progression of asbestosis in the sheep model by bronchoalveolar lavage and pulmonary function tests.

Abstract

To study the relationship between the results of bronchoalveolar lavage and pulmonary function tests during induction and progression of asbestosis, three groups of six sheep were exposed repeatedly by intratracheal injection to either saline (controls), low doses of Canadian chrysotile UICC asbestos (cumulative exposure 328 mg) (low-dose group), or high doses of the same fibres (cumulative dose 2282 mg) (high-dose group) until there was clear evidence of alveolitis from the lung biopsy specimens of all sheep of the high-dose group. During the course of this induction and for the following eight months lung biopsies, bronchoalveolar lavage and pulmonary function tests were performed at two-month intervals. At the time of initial alveolitis in the high-dose group there was no significant change in the cellularity of the bronchoalveolar lavage fluid, but static lung compliance (C5t), vital capacity (VC), arterial oxygen tension (Pao2), and diffusion capacity (DL/VA) were significantly lower than in the other groups. In the following months, as the alveolitis evolved into a fibrosing process, macrophages and neutrophils from the bronchoalveolar lavage fluid increased significantly and pulmonary function deteriorated. Proteins and enzymes in the bronchoalveolar lavage fluid also increased significantly in the high-dose group. These data show that in the sheep model of asbestosis simple tests of pulmonary function correlate well with histological changes and changes in the bronchoalveolar lavage fluid in the course of the disease and can be used to assess progression of asbestosis.

Hyaluronan (hyaluronic acid) in lung lavage of asbestos-exposed humans and sheep

“…All pulmonary function tests in sheep were performed as described previously [6]. The total lung capacity was determined by syringe lung inflation to a transpulmonary pressure of 35 + 5 cmH20.…”

“…Bronchoalveolar lavage was performed in sheep under topical anesthetic with lidocaine as described previously (6). The BALF aspirated from three infusions of 50 ml PBS was centrifuged (500 x g, 5 min), and the supernatant was assayed for albumin and hyaluronan.…”

The Relationship between Respiratory Impairment and Asbestos-related Pleural Abnormality in an Active Work Force

“…The validity of this method of deriving and index of Gallium uptake was examined by Begin et al in a· sheep model of asbestosis (88)(89)(90)(91).…”

Immunohistochemical localization of transforming growth factor-β and insulin-like growth factor-I in asbestosis in the sheep model

“…The sheep model of asbestosis has contributed significantly to our understanding of the basic mechanisms of this pneumoconiosis [3,4,[7][8][9]27]. Well-established clinical techniques such as pulmonary function tests, chest radiography, gallium lung scanning, and bronchoalveolar lavage have been applied to this experimental animal model and have shown that this model closely simulates human disease [3-5, 7-9, 27].…”