title: Attenuation of very late antigen-5-mediated adhesion of bone marrow-derived mast cells to fibronectin by peptides with inverted hydropathy to EF-hands.
abstract: Release of allergic mediators from mast cells is enhanced by very late Ag (VLA)-5-mediated interaction of these cells with fibronectin. In this report, we show that VLA-5-mediated adhesion of bone marrow-derived mast cells to fibronectin can be induced by two different pathways: first, FcepsilonRI clustering, which depends on calmodulin activation and extracellular Ca(2+), and, second, by Mn(2+) stimulation, which is independent of calmodulin activation and antagonized by Ca(2+). Previous studies have shown the presence of several cation-binding domains in VLA-5 that are homologous to the calcium-binding EF-hands of calmodulin. To show a role for EF-hands of different proteins in VLA-5-mediated adhesion, we used calcium-like peptides (CALP), CALP1 and CALP2, designed to bind to EF-hands based on inverted hydropathy. CALP1 and, more potently, CALP2 inhibited FcepsilonRI-induced adhesion to fibronectin via different mechanisms. The target for the effects of CALP1 and 2 on FcepsilonRI-induced adhesion and degranulation was intracellular and likely involved calmodulin. Interestingly only CALP2 was able to inhibit Mn(2+)-induced calmodulin-independent adhesion by interfering with an extracellular target, which is probably VLA-5. We conclude that CALP1 and 2 can inhibit VLA-5-mediated adhesion of mast cells to fibronectin through binding to EF-hands of multiple proteins, and that these peptides can be used as lead compounds for the development of future therapy against allergy.
authors.affiliation: Department of Pharmacology and Pathophysiology, Utrecht Institute for Pharmaceutical Sciences, Universiteit Utrecht, Utrecht, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Houtman
authors.forename: R
authors.initials: R
authors.lastname: Ten Broeke
authors.forename: J E
authors.initials: JE
authors.lastname: Blalock
authors.forename: M
authors.initials: M
authors.lastname: Villain
authors.forename: A S
authors.initials: AS
authors.lastname: Koster
authors.forename: F P
authors.initials: FP
authors.lastname: Nijkamp
mesh_terms: D000276:Adjuvants, Immunologic / Q000138:chemical synthesis / Q000494:pharmacology; D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology; D002147:Calmodulin / Q000502:physiology; D002352:Carrier Proteins / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D002413:Cations, Divalent / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000276:immunology; D015550:Cell Degranulation / Q000187:drug effects / Q000276:immunology; D020832:EF Hand Motifs / Q000276:immunology*; D005110:Extracellular Space / Q000502:physiology; D005353:Fibronectins / Q000276:immunology / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins; D008345:Manganese / Q000494:pharmacology; D008407:Mast Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009842:Oligopeptides / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D010455:Peptides; D017469:Receptors, Fibronectin / Q000502:physiology*; D017455:Receptors, IgE / Q000502:physiology
chemical_list: D000276:Adjuvants, Immunologic; C420971:CALP2 protein, synthetic; D002121:Calcium Channel Blockers; D002147:Calmodulin; D002352:Carrier Proteins; D002413:Cations, Divalent; D005353:Fibronectins; D036341:Intercellular Signaling Peptides and Proteins; D009842:Oligopeptides; D010455:Peptides; D017469:Receptors, Fibronectin; D017455:Receptors, IgE; C412708:calcium-like peptide CALP1; D008345:Manganese; D002118:Calcium