Methyl ester of n‐formylmethionyl‐leucyl‐phenylalanine. Chemotactic responses of human blood monocytes and inhibition of gold compounds

Abstract

N‐formylmethionyl‐leucyl‐phenylalanine, a potent chemotactic peptide for human polymorphonuclear leukocytes, is less chemotactic for human blood monocytes. Esterification of the N‐formylated tripeptide enhances its chemotactic activity for monocytes by more than 4 logs, whereas a decrease by 3 logs is observed for polymorphonuclear leukocytes. These results indicate the participation of the C‐terminal carboxyl group in chemotaxis of different cell types. We have also observed the selective inhibition of chemotactic responsiveness of human blood monocytes by a clinically useful antirheumatic drug, sodium aurothiomalate. Since this is the first in vitro cell migration model of inflammation in which gold compounds have demonstrated activity in micromolar concentrations, it suggests a site of action for this antirheumatic drug.