Abstract
We investigated the functions of peripheral blood monocytes (Mo) and alveolar macrophages (AM) from patients with interstitial lung disease, especially those with sarcoidosis, and normal subjects. AM were obtained by bronchoalveolar lavage (BAL) and Mo from venous blood. We determined the absolute count, chemotaxis, phagocytic index, lysosomal enzyme activity, cytotoxicity, superoxide anion release, IL-1 production and serum and BAL fluid levels of angiotensin converting enzyme (ACE), lysozyme and fibronectin.
In the peripheral blood of sarcoidosis patients, the absolute number of Mo was significantly increased compared with normal subjects, moreover the absolute count of Mo in bone marrow was increased. There was a close correlation between the absolute numbers of Mo in peripheral blood and bone marrow. Chemotaxis and phagocytic index were decreased in patients with sarcoidosis, however superoxide anion production, beta-galactosidase activity and serum levels of ACE and lysozyme were higher in sarcoidosis patients than in normals. There were no differences in cytotoxicity and IL-1 production between sarcoidosis patients and normal subjects.
There was no difference in the number of between sarcoidosis patients and normals. Chemotaxis and phagocytic index, though, unlikely in peripheral blood Mo, were increased significantly in sarcoidosis patients compared with normals. Furthermore, the levels of ACE and fibronectin were significantly higher in sarcoidosis patients than in normals as well. However beta-galactosidase activity was decreased in sarcoidosis patients compared with normals. There was no difference in IL-1 production between sarcoidosis patients and normal subjects.
These data suggest that peripheral blood monocytes arise in the bone marrow and become alveolar macrophages and that both peripheral blood monocytes and alveolar macrophages are activated.
