Phagocytic properties and organelle motility of pulmonary macrophages from smokers and nonsmokers estimated in vitro by magnetometric means

Monolayer cultures of pulmonary macrophages (PM) from 11 smokers (S) and 9 nonsmokers (NS) were incubated with submicrometric ferromagnetic Fe3O4 particles for one hour. After magnetization by an externally applied pulse magnetic field, the aligned Fe3O4 particles, located in the phagosomes and secondary lysosomes of the PM, emanated a remanent magnetic field which decayed with time. The initial field strength, B0, which is proportional to the amount of phagocytosed Fe3O4 particles, was 13.24 nT (SE 0.79 nT) in S and 11.74 nT (SE 1.39 nT) in NS. Ten nT correspond to roughly 4 micrograms Fe3O4. The initial rate of decay of the remanent field (during the first 60 s after magnetization), lambda 0, is proportional to the rate of particle misalignment. Therefore, lambda 0, is hypothesized to be an estimate of organelle motility. It was found to be the same in S and in NS, being 3.14 x 10(-3).s-1 (SE 0.18 x 10(-3).s-1) in S and 3.17 x 10(-3).s-1) (SE 0.22 x 10(-3).s-1) in NS. These results suggest that, in vitro, there is no difference in phagocytic activity and organelle motility in PM from S and NS.