Inhibitory effect of Pseudomonas aeruginosa on the phagocytic and killing activity of rabbit polymorphonuclear leukocytes: mechanisms of action of a polymorphonuclear leukocyte inhibitor.

The polymorphonuclear leukocyte (PMN) inhibitor isolated from a strain of Pseudomonas aeruginosa which is resistant to the phagocytic and killing activities of rabbit PMN inhibited migration of PMN and engulfment of latex particles by PMN. In studies of the bactericidal metabolism of PMN, the PMN inhibitor did not inhibit the intracellular activity and extracellular release of lysosomal enzymes. However, the PMN inhibitor caused a decrease of Nitro Blue Tetrazolium reduction. The PMN inhibitor had a cytotoxic effect on PMN and inhibited [14C]tyrosine uptake in intact PMN inhibitor had no inhibitory effect on protein synthesis in cell extracts.