Abstract
In order to investigate the pathophysiological role of pulmonary alveolar macrophages (PAMs) in pulmonary diseases, we measured the biological and biochemical activities of PAMs obtained from normal volunteers and patients with pulmonary diseases with those of rat PAMs as control. In particular we examined the effect of smoking on the function of human PAMs.
PAMs were obtained from two groups; 11 normal volunteers aged 24±1 years (mean±SD) and 27 patients with well localized pulmonary disease aged 63±12 years, by segmental bronchoalveolar lavage. The lavaged site of the patient group was free of lesions. Only specimens in which percentage and viability of PAMs was over 75%, were used as test samples.
1) The number of PAMs was about 1.5 times larger in the smokers than in the nonsmokers, and their mean viability was about 85%, in both groups.
2) The O2 consumption in cell level, protein content and acid phosphatase activity of PAMs from the smokers were significantly (1.5-3-fold) higher than those from the nonsmokers in both groups.
3) In the patient group, per cent adherence of PAMs from smokers was significantly lower than in non-smokers.
4) Phagocytic activity of PAMs from normal volunteers was measured with heterogeneous erythrocytes. The erythrophagocytic activity of PAMs from both smokers and nonsmokers were markedly higher with ORBC coated with anti-ORBC rabbit IgG than with that not coated with the IgG. When SRBC coated with both anti-SRBC rabbit IgM and human complement was used as erythrocyte, the erythrophagocytic activity was significantly lower in the smokers than in the nonsmokers.
5) Levels of O2 consumption at the cell level of rat PAMs were similar to those of human PAMs from nonsmokers, but acid phosphatase and β-glucuronidase activities of rat PAMs were different from those of human PAMs.
These results indicate that the number and functions of PAMs are affected by smoking, and that the effect of smoking on the different functions of PAMs differs according to the individual.
