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Bone resorption activity of particulate‐stimulated macrophages
Author(s) -
Glant Tibor T.,
Jacobs Joshua J.,
Molnár Gyöngyi,
Shanbhag Arun S.,
Valyon Márta,
Galante Jorge O.
Publication year - 1993
Publication title -
journal of bone and mineral research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.882
H-Index - 241
eISSN - 1523-4681
pISSN - 0884-0431
DOI - 10.1002/jbmr.5650080907
Subject(s) - bone resorption , resorption , macrophage , chemistry , prostaglandin e , in vivo , endocrinology , calcium , prostaglandin e2 , medicine , in vitro , biochemistry , biology , microbiology and biotechnology
Particulate wear debris from bone cement or prosthetic components can stimulate macrophages to cause bone resorption in a dose‐dependent manner. This bone resorption activity of particulate‐stimulated macrophages is associated with increased levels of both prostaglandin E 2 (PGE 2 ) and interleukin‐1 (IL‐1). In this study we compared the effect of particulate size, concentration, and composition on the secretion of IL‐1 and PGE 2 by peritoneal macrophages and on the bone‐resorbing activity of conditioned medium (CM) harvested from particulate‐challenged macrophages. Particulates (titanium, Ti; polymethylmethacrylate, PMMA; and polystyrene, PS) only with phagocytosable size stimulated peritoneal macrophages to secrete IL‐1 and PGE 2 in a dose‐ and time‐dependent manner. Ti particles (1–3 μm) exhibited significantly enhanced bone‐resorbing activity measured as 45 Ca release. The maximum bone‐resorbing response was observed at a concentration of 0.1% Ti (approximately 10–15 Ti particulates per cell), which also corresponded with the highest IL‐1 levels measured in particulate‐challenged CM. This was measured using either conditioned media from Ti‐stimulated macrophages or in cocultures of calvarial bone and macrophages in the presence of Ti. Exogenous PGE 2 and recombinant human IL‐1 could significantly increase the 45 Ca release; indomethacin (IM) significantly reduced both the spontaneous calcium efflux and active 45 Ca release from in vivo labeled calvarial bones. However, IM and/or anti‐Il‐1 antibodies could suppress only partly the macrophage‐mediated bone resorption, indicating that, in a macrophage‐bone coculture system, factors other than PGE 2 and IL‐1 also may regulate particulate‐induced bone resorption, probably involving multiple cell types.