Size, adherence, and phagocytic characteristics of alveolar macrophages harvested 'early' and 'later' during bronchoalveolar lavage.

Alveolar macrophages (AM) harvested by sequential lung lavage procedures are physically, biochemically, and functionally heterogeneous. The present studies were undertaken in order to determine if such AM heterogeneity is a function of their sequential removal from the lung during episodic bronchoalveolar lavage. Our results demonstrate that AM harvested during 'early' lung wash cycles and during 'later' sequential lung wash cycles are essentially identical in terms of their: (1) abilities to exclude a vital dye; (2) volume distributions; (3) plastic substrate adherence characteristics; and (4) Fc gamma receptor-mediated phagocytic activities.