Potentiation of polymorphonuclear leukocyte motile functions by 2,3-dihydroxybenzoic acid

DHB potentiates PMN phagocytosis of opsonized lipopolysaccharide-coated PO droplets by 53% to 45% and chemotaxis by 36% to 10% at 10-3M and 10-4M concentrations, respectively. The effect is reversible in vitro. In the presence of DHB, PMNs released significantly less superoxide and H2O2 to the extracellular media but were able to oxidize 1-14C-glucose normally during phagocytosis. Although iodination of opsonized particles was decreased in the presence of DHB, the PMNs were able to kill Staphylococcus aureus 502A normally. These results support the hypothesis that directed cell movement and phagocytosis can be enhanced by protecting the PMN membrane against auto-oxidative damage from scavenging superoxide and H2O2 by means of DHB.