Chemotactic Peptide Ligands for Formylpeptide Receptors Influencing Inflammation

ABSTRACT Bacterial peptide fMet-Leu-Phe (fMLF) is one of the first identified chemoattractants for phagocytic leukocytes by interacting with two seven transmembrane, G protein-coupled formylpeptide receptors, FPR, and its variant FPRL1. Recently a number of novel and host-derived formylpeptide receptor agonist peptides have been identified. These agonists selectively activate one or more formylpeptide receptors including another FPR variant FPRL2. Activation of formylpeptide receptors by peptide agonists results in increased cell chemotaxis, phagocytosis, and release of proinflammatory mediators by leukocytes. Injection of peptide agonists in mice also promotes antibody responses. Therefore, formylpeptide receptor agonists may play important roles in the pathogenesis of inflammatory and immunological diseases.