The Glucose Concentration Modulates N-Formyl-Methionyl-Leucyl-Phenylalanine (fMet-Leu-Phe)-Stimulated Chemokinesis in Normal Human Neutrophils

The effects of glucose concentration on the chemokinetic effects of the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMet-Leu-Phe) was evaluated for normal human neutrophils using a direct microscopic assay. fMet-Leu-Phe increased the rate of locomotion in the absence of glucose, but the chemokinetic effect of fMet-Leu-Phe was most potent at 5mM glucose and not further changed at 15 mM glucose. The chemokinetic effects of fMet-Leu-Phe and glucose were essentially the same in blood clot-isolated and gradient-isolated neutrophils. However, in gradient-isolated neutrophils, the rate of locomotion under different experimental conditions was strictly negatively correlated to the fraction of non-locomoting cells and the degree of adhesion to the substratum. These results indicate that the chemokinetic effects of fMet-Leu-Phe are regulated by the glucose concentration by inducing locomotor activity in otherwise non-locomoting cells and by improving adhesion to the substratum.