title: LPS increases biomaterial degradation by human monocytes in vitro.
abstract: Different cell lines are involved during an immunological reaction, principally lymphocytes and monocytes. Monocyte/macrophage cells, which are among the first to appear in wound-healing and infection sites, are largely implicated in phagocytosis and could be involved in calcium-phosphate degradation. Their role in these processes may relate to cytokine secretions and/or their sensitivity to certain cytokines. We tested the behavior of human monocytes placed on the surface of biphasic calcium-phosphate (BCP) tablets in the presence of two lipopolysaccharide (LPS) concentrations. After short-term culture (48 h), cytokine release (IL-1beta, IL-6) was measured by ELISA, and morphological cell events and biomaterial degradation were observed in scanning electron microscopy. BCP surface pits were noted near cells stimulated by 0.5 microg/mL LPS but were not apparent with 10 microg/mL LPS. The number of lacunae on BCP was increased after LPS treatment of human monocytes. An upmodulation of IL-1beta and IL-6 (in culture medium) released by LPS-activated human monocytes was observed, indicating good cell stimulation. This study demonstrates that LPS-activated human monocytes can degrade the surface of calcium-phosphate ceramic and confirms the role of human monocytes in biomaterial degradation.
authors.affiliation: Centre de Recherche sur les Matériaux d'Intérêts Biologiques, Faculté de Chirurgie Dentaire, Nantes, France.
authors.forename: M
authors.initials: M
authors.lastname: Benahmed
authors.forename: D
authors.initials: D
authors.lastname: Heymann
authors.forename: P
authors.initials: P
authors.lastname: Pilet
authors.forename: J
authors.initials: J
authors.lastname: Bienvenu
authors.forename: G
authors.initials: G
authors.lastname: Daculsi
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D001673:Biodegradation, Environmental / Q000187:drug effects*; D002130:Calcium Phosphates / Q000737:chemistry; D002478:Cells, Cultured; D002516:Ceramics; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D007375:Interleukin-1; D015850:Interleukin-6; D008070:Lipopolysaccharides