Cytotaxin receptors of neutrophils: evidence that F-methionyl peptides and pepstatin share a common receptor.

Pepstatin, a chemotactic microbial pentapeptide, competes with f-Met-Leu-[3H]Phe for binding to human neutrophils. Furthermore, porcine neutrophils, which neither specifically bind nor respond chemotactically to the synthetic f-methionyl peptides, also fail to respond chemotactically to pepstatin. These results suggest that pepstatin shares a receptor on the neutrophil with f-methionyl peptides, despite their completely different amino acid compositions. The specificity of this cytotaxin receptor may therefore be broader than expected and depend on ligand characteristics distinct from primary structure.