title: Syndecan-1 is involved in osteoprotegerin-induced chemotaxis in human peripheral blood monocytes.
abstract: Chronic inflammation is characterized by tissue infiltration with monocytes/macrophages, which possess broad proinflammatory, destructive, and remodeling capacities. Elevated levels of osteoprotegerin, an important regulator of differentiation and activation of osteoclasts that also affects different cells of the immune system, were found in the serum of patients with chronic inflammatory diseases. The study of whether osteoprotegerin affects monocyte locomotion in vitro and the possible mechanisms and pathways involved was investigated using Boyden microchemotaxis chambers and Western blot analyses. Osteoprotegerin significantly stimulated monocyte chemotaxis, whereas preincubation of monocytes with osteoprotegerin inhibited monocyte migration toward optimal concentrations of regulated upon activation normal T cell expressed and secreted, monocyte chemotactic protein -1, and procalcitonin. The effects of osteoprotegerin were abolished by pretreating cells with heparinase I and chondroitinase or antibodies against the ectodomain of syndecan-1. Osteoprotegerin signaling was shown to involve protein kinase C, phosphatidylinositol 3-kinase/Akt, and tyrosine kinase. Data suggest that osteoprotegerin affects monocyte mi-gration and protein kinase C and phosphatidylinositol 3-kinase/Akt activation via syndecan-1. Osteoprotegerin-induced deactivation of monocyte chemotaxis toward different chemokines is due to interaction of osteoprotegerin with heparan sulfate and chondroitin sulfate.
authors.affiliation: Division of General Internal Medicine, Department of Internal Medicine, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria.
authors.forename: Birgit A
authors.initials: BA
authors.lastname: Mosheimer
authors.forename: Nicole C
authors.initials: NC
authors.lastname: Kaneider
authors.forename: Clemens
authors.initials: C
authors.lastname: Feistritzer
authors.forename: Angela M
authors.initials: AM
authors.lastname: Djanani
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Sturn
authors.forename: Josef R
authors.initials: JR
authors.lastname: Patsch
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Wiedermann
mesh_terms: D002465:Cell Movement / Q000187:drug effects; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D002810:Chondroitinases and Chondroitin Lyases / Q000494:pharmacology; D006023:Glycoproteins / Q000494:pharmacology*; D019763:Heparin Lyase / Q000494:pharmacology; D006801:Humans; D008562:Membrane Glycoproteins / Q000502:physiology*; D009000:Monocytes / Q000276:immunology*; D053244:Osteoprotegerin; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D011493:Protein Kinase C / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011509:Proteoglycans / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; D053668:Syndecan-1; D053667:Syndecans; D042461:Vascular Endothelial Growth Factor A / Q000502:physiology; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D002810:Chondroitinases and Chondroitin Lyases; D006023:Glycoproteins; D019763:Heparin Lyase; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D019869:Phosphatidylinositol 3-Kinases; D011493:Protein Kinase C; D017346:Protein Serine-Threonine Kinases; D011509:Proteoglycans; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; D053668:Syndecan-1; D053667:Syndecans; D042461:Vascular Endothelial Growth Factor A; D019061:src-Family Kinases; C508241:SDC1 protein, human; C506030:TNFRSF11B protein, human; C494918:AKT1 protein, human