title: The anti-infective peptide, innate defense-regulator peptide, stimulates neutrophil chemotaxis via a formyl peptide receptor.
abstract: The anti-infective peptide, innate defense-regulator peptide (IDR-1), has been selectively reported to modulate the innate immune response. We found that IDR-1 stimulates the chemotactic migration in human neutrophils. Moreover, IDR-1-induced neutrophil chemotaxis was completely blocked by pertussis toxin, suggesting the importance of the G(i) protein in this process. The mechanism governing the IDR-1-induced neutrophil chemotaxis was found to be completely inhibited by the formyl peptide receptor (FPR) antagonist; cyclosporin H. IDR-1 was also found to induce chemotactic migration in FPR but not in vector-expressing HCT116 cells. Meanwhile, IDR-1 failed to stimulate superoxide anion generation and intracellular calcium increase in human neutrophils. Furthermore, IDR-1 was found to inhibit fMLF (an FPR agonist)-induced superoxide generation and calcium signaling in human neutrophils and FPR-expressing HCT116 cells. Taken together, the results demonstrate that IDR-1 is a partial agonist for FPR and further, stimulates neutrophil chemotaxis without inducing calcium signaling and superoxide generation.
authors.affiliation: Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714, Republic of Korea.
authors.forename: Ha Young
authors.initials: HY
authors.lastname: Lee
authors.forename: Yoe-Sik
authors.initials: YS
authors.lastname: Bae
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage*; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D018375:Neutrophil Activation / Q000187:drug effects / Q000502:physiology*; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology*; D010455:Peptides / Q000008:administration & dosage*; D044042:Receptors, Formyl Peptide / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D010455:Peptides; D044042:Receptors, Formyl Peptide