Open AccessSyndecan-1 Is Involved in Osteoprotegerin-Induced Chemotaxis in Human Peripheral Blood Monocytes
Author(s) -
Birgit A. Mosheimer,
Nicole C. Kaneider,
Clemens Feistritzer,
Angela Djanani,
Daniel H. Sturn,
Josef R. Patsch,
Christian J. Wiedermann
Publication year - 2005
Publication title -
the journal of clinical endocrinology and metabolism/journal of clinical endocrinology and metabolism
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.206
H-Index - 353
eISSN - 1945-7197
pISSN - 0021-972X
DOI - 10.1210/jc.2004-1895
Subject(s) - osteoprotegerin , monocyte , chemistry , chemotaxis , chemokine , microbiology and biotechnology , endocrinology , medicine , inflammation , biology , biochemistry , receptor , activator (genetics)
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.