title: The influence of glycosaminoglycans on IL-8-mediated functions of neutrophils.
abstract: Glycosaminoglycans (GAGs) of the extracellular matrix (ECM) contribute to the regulation of physiological processes by binding various immune-competent proteins. Due to their large structural diversity, the analysis of the binding properties and their functional consequences is challenging. The cytokine interleukin-8 (IL-8) is involved in the recruitment of neutrophils to inflammatory sites. Here, we investigated the interaction of heparin hexasaccharides and recombinant human IL-8, consisting of 77 amino acids using fluorescence and NMR spectroscopy. A dissociation constant of 2.0±0.4 μM was determined for the heparin-IL-8 complex, which is slightly higher than what has been found for chondroitin-6-sulfate (K(D)=1.4±0.4 μM) [Pichert, A.; Samsonov, S. A.; Theisgen, S.; Thomas, L.; Baumann, L.; Schiller, J.; Beck-Sickinger, A. G.; Huster, D.; Pisabarro, M. T. Glycobiology2012, 22, 134-145], suggesting an important role of the sulfate group at position 6 of the second ring in the disaccharide unit of the GAGs in this interaction. In addition, the influence of long-chain hyaluronan, chondroitin sulfate, and heparin on IL-8-induced chemotaxis and oxidative activity of neutrophils was examined. Only the incubation of heparin with IL-8 affected the IL-8-mediated chemotaxis of neutrophils. However, all investigated GAGs enhanced the IL-8-induced formation of reactive oxygen species in neutrophils, which is an entirely new finding. This work provides a representative example of how protein functions can be regulated by different GAGs of the ECM.
authors.affiliation: Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse 16-18, D-04107 Leipzig, Germany.
authors.forename: Denise
authors.initials: D
authors.lastname: Schlorke
authors.forename: Lars
authors.initials: L
authors.lastname: Thomas
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Samsonov
authors.forename: Daniel
authors.initials: D
authors.lastname: Huster
authors.forename: Jürgen
authors.initials: J
authors.lastname: Arnhold
authors.forename: Annelie
authors.initials: A
authors.lastname: Pichert
mesh_terms: D001665:Binding Sites; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects; D002809:Chondroitin Sulfates / Q000737:chemistry* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005109:Extracellular Matrix / Q000737:chemistry; D006493:Heparin / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D006820:Hyaluronic Acid / Q000737:chemistry* / Q000494:pharmacology; D016209:Interleukin-8 / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011485:Protein Binding; D017382:Reactive Oxygen Species / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship
chemical_list: D016209:Interleukin-8; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; D006820:Hyaluronic Acid; D006493:Heparin; D002809:Chondroitin Sulfates