Dispersed Human Lung Mast Cells

The present investigation was designed to study the histamine release and pharmacologic characteristics off dispersed human lung mast cells, particularly in comparison with parenchymal tissue fragments. Dispersed human lung mast cells were prepared by enzymatic treatment (yield, 0.5 to 2 × 106 mast cells/g tissue). Purity was 1 to 8% (mean, 3.6% ± 0.7%), and histamine content varied from 2 to 6 pg/cell (mean, 3.6 ± 0.5 pg/cell). Release, studied using anti-IgE as the stimulus, was relatively rapid, being essentially complete within 15 min when high concentrations of anti-IgE (⩾ 0.3 eg/ml) were used and was not enhanced by phosphatidyl serine. The concentration of drug required to inhibit histamine release by 50% in dispersed cells for a series of pharmacologic agents, including the β-adrenergic agent fenoterol, the prostaglandin E2, and the phosphodiesterase inhibitor isobutylmethylxanthine, were 0.1 to 1 eM, 50 eM, and 0.5 mM, respectively; similar results were obtained in simultaneous experiments perfor...