STUDIES OF PHAGOCYTIC AND KILLING ACTIVITIES OF ALVEOLAR MACROPHAGES IN PATIENTS WITH SARCOIDOSIS

Phagocytosis and killing activities of alveolar macrophages were compa red in 17 patients with stage 1 sarcoidosis and 6 healthy controls. Th e average total cell count of bronchoalveolar lavage fluid from patien ts with sarcoidosis was 7.8 +/- 7.5 x 10(6) cells; 70.4 +/- 15% of the se cells were alveolar macrophages and 25.9 +/- 16.2% lymphocytes. Ave rage total cell count from controls was 8.33 +/- 8.6 x 10(6) cells, wi th 92.7 +/- 5.9% alveolar macrophages and 6.6 +/- 4.4% lymphocytes. Pu rified alveolar macrophages were tested in in vitro antibacterial assa ys using S. aureus as a test microbe. Moderate decreases in the kineti cs of staphylococcal ingestion were detected in the sarcoidosis group. The intracellular killing activity of macrophages was much lower in t he patients with sarcoid than in control subjects. In a pilot study, i ntracellular killing activity of macrophages from 1 patient with sarco idosis was greatly enhanced by 24 hr treatment with transfer factor. I n summary, alveolar macrophages from patients with radiographic stage 1 sarcoidosis have decreased bacterial ingestion and intracellular kil ling activities. These results suggest that macrophages undergo comple x functional changes in sarcoidosis that may influence both disease de velopment and host defenses.