Proliferative Capacity of Human Alveolar Macrophage

THE alveolar macrophage plays a crucial role in the pulmonary ecology and is a first line of cellular defence for the lung 1,2 . Although animal studies indicate that pulmonary macrophages originate from the bone marrow 3–5 , little is known of the origin or fate of these cells in man. Cigarette smokers, however, are known to have substantially increased numbers of macrophages in the lung 1,6 and the pulmonary macrophages in smokers demonstrate characteristic morphologic and functional attributes 1,2,7,8 .