title: In vitro evaluation of the inflammatory activity of ultra-high molecular weight polyethylene.
abstract: To understand the inflammatory potential of oxidised ultra high molecular weight polyethylene (ox-UHMWPE) compared with the virgin one (UHMWPE), we analysed in vitro the predisposition of their interaction with plasma proteins and cells involved in the inflammatory response. The adsorption on the surface of the two materials of adhesion proteins (Fibronectin and Albumin), and pro-inflammatory proteins (IgG and IgA) have been studied. Moreover, we have evaluated the materials effect on complement activation and on macrophages and monocytes-neutrophils behaviour. The two UHMWPE chemical forms adsorbed all the proteins studied; the only difference was in complement activation. Enzyme immunoassay results evidenced higher levels of factor Bb and iC3b in plasma after the contact with the oxidised form. Physico-chemical properties of the oxidised UHMWPE affected the attachment of the cells as demonstrated by macrophages adhesion experiments. UHMWPE favoured only a limited peritoneal macrophages (PMs) spreading (round-shaped cells); the cell spreading and presence of microvilli on the cell membranes was evident in the case of the oxidised form, suggesting the activation of these cells on this chemical form. Ox-UHMWPE evidenced a statistically significative increase in chemiluminescence values respect to human unstimulated peripheral blood mononuclear cells, an index of increased cell release of reactive oxygen metabolites. In conclusion, UHMWPE oxidative degradation with its chemical modification induces monocytes-neutrophils chemiluminescence activation and PMs morphology changes correlated with macrophage activation, data consistent with the complement activation results obtained in this study; such modifications, along with changes in mechanical properties, are related to implant failure.
authors.affiliation: Department of Medical Sciences, Human Anatomy, University of Eastern Piedmont, A Avogadro, Via Solaroli 17, Novara 28100, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bosetti
authors.forename: L
authors.initials: L
authors.lastname: Zanardi
authors.forename: P
authors.initials: P
authors.lastname: Bracco
authors.forename: L
authors.initials: L
authors.lastname: Costa
authors.forename: M
authors.initials: M
authors.lastname: Cannas
mesh_terms: D000327:Adsorption; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000633:toxicity*; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D003167:Complement Activation / Q000187:drug effects; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D007070:Immunoglobulin A / Q000378:metabolism; D007074:Immunoglobulin G / Q000378:metabolism; D066298:In Vitro Techniques; D007249:Inflammation / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D018836:Inflammation Mediators / Q000378:metabolism; D007595:Joint Prosthesis; D008163:Luminescent Measurements; D008262:Macrophage Activation / Q000187:drug effects; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D008422:Materials Testing; D051379:Mice; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D011095:Polyethylenes / Q000737:chemistry / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012709:Serum Albumin / Q000378:metabolism
chemical_list: D001672:Biocompatible Materials; D005353:Fibronectins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D018836:Inflammation Mediators; D011095:Polyethylenes; D017382:Reactive Oxygen Species; D012709:Serum Albumin; C111601:ultra-high molecular weight polyethylene