Neutrophil responsiveness to chemoattractant tripeptide in rheumatoid arthritis.

Neutrophils isolated from medication-free rheumatoid arthritis (RA) patients were assayed for responsiveness to the bacterial chemoattractant tripeptide formyl-methionyl-leucyl-phenylalanine (f-Met-Leu-Phe). Rheumatoid arthritis neutrophil preparations contained significantly lower percentages of rapidly migrating cells. This relative hyporesponsiveness of RA neutrophils was related to impaired sensing of chemotactic gradients. Rheumatoid neutrophil abnormalities in sensing of and responding to chemotactic gradients were not associated with resting or f-Met-Leu-Phe-induced changes in arachidonic acid metabolism.