The ultrastructure of bronchial macrophages and lymphocytes in sarcoidosis

A physical interaction between macrophages and lymphocytes was observed more frequently in bronchial lavage fluid obtained from patients with sarcoidosis than from normal volunteers, irrespective of their history of smoking. In this spontaneous interaction more than two lymphocytes were commonly seen adhering to a macrophage without evidence of cytoplasmic bridging or membrane fusion. To a greater extent than in normal volunteers, macrophages from patients with sarcoidosis were characterized by the appearance of a more highly irregular cell surface, more membrane bound inclusions, however, was positively correlated with the smoking history of the individual, and the number of surface projections (microvilli) of macrophages from smokers appeared to be reduced. Significant differences were not apparent in the nuclear or cellular diameters of macrophages from sarcoid and normal individuals.