title: Importance of the surface area ratio on cytokines production by human monocytes in vitro induced by various hydroxyapatite particles.
abstract: A possible complication associated with the implantation of hydroxyapatite (HA)-based prosthesis is the release of particles. Those particles can be phagocyted by monocytes that are among the first cells to colonize the inflammatory site. The activated monocytes produce inflammatory mediators, such as cytokines, which cause osteoclasts activation. It has previously been demonstrated using a surface area ratio (ratio of the total surface of the given particles to the surface area of cells) of 1 to 1 that there was a correlation between the expression and production of cytokines induced by HA. The present work studies the effect of physical characteristics of HA particles on the production of various inflammatory cytokines (tumour necrosis factor-alpha, interleukin (IL)-6, and IL-8) and anti-inflammatory cytokine (IL-10). However, the experiments were performed using a surface area ratio of 10 to 1. Our data demonstrate that all the particles, whatever their characteristics, induced a high expression of cytokines but the production was different, meaning that there was a post-transcriptional regulation. The size and sintering temperature seemed to be a characteristics that were less important compared to the shape; the needle particles appeared to induce the most important production of all the cytokines studied.
authors.affiliation: Ultramicro Analytical Immunochemistry Resource, Division of Bioengineering and Physical Science, Office of Research Services, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Alexia
authors.initials: A
authors.lastname: Grandjean-Laquerriere
authors.forename: Patrice
authors.initials: P
authors.lastname: Laquerriere
authors.forename: Moncef
authors.initials: M
authors.lastname: Guenounou
authors.forename: Dominique
authors.initials: D
authors.lastname: Laurent-Maquin
authors.forename: Terry M
authors.initials: TM
authors.lastname: Phillips
mesh_terms: D001672:Biocompatible Materials / Q000009:adverse effects*; D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D017886:Durapatite / Q000009:adverse effects*; D006801:Humans; D008422:Materials Testing; D009000:Monocytes / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D010316:Particle Size; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D016207:Cytokines; D017886:Durapatite