Intracellular Motility of Pulmonary Macrophages from Smokers and Nonsmokers

Abstract

The pulmonary macrophages (PM) with their locomotory, phagocytic and lytic potentials are an essential line of defence in the lungs, keeping the airway and alveolar surfaces clean and sterile (Bowden, 1987). Stimulating collagen producing fibroblasts and secreting lysosomal proteolytic enzymes (collagenase, elastase), the same cells, however, also participate in the pathogenesis of lung diseases, such as fibrosis (Leibovich et al., 1986) and emphysema (Brain, 1988). An increased inhalation of particles causes the number of PM to increase. In chronic smokers (S) the number of PM has been found to be manifold increased as compared to nonsmokers (NS) (Crapo et al., 1982). Moreover, the PM from S have more and larger phagosomes and secondary lysosomes (organelles), containing indigestible material (Pratt. et al., 1971). Thus, we expected the PM of S to exhibit a more extensive phagocytic activity and organelle motion than PM from NS. To test this hypothesis, we harvested PM from human S and NS by bronchoalveolar lavage (BAL) and analysed the cells by magnetometric means (cytomagnetometry). This technique consists of the measurement of the remanent magnetic field, that emanates from macrophages which have phagocytized ferromagnetic particles (Fe₃O₄), after magnetization by an external magnetic field.