Stimulation of PMN OSM production. PMN (10⁷/mL) were incubated for 20 hours with various stimulating agents at the concentrations indicated in Materials and Methods. OSM was assayed in the cell-free supernatants. Control cells (CTRL) were incubated with medium alone. Results are expressed as the means ± SEM of six independent experiments. *P < .05 compared with control cells.