title: Endotoxin contamination contributes to the in vitro cytokine-inducing activity of osteopontin preparations.
abstract: Recently, both native and recombinant preparations of human osteopontin (OPN) have been shown to be able to induce the production of several proinflammatory cytokines in human peripheral blood mononuclear cells (PBMCs) or purified monocytes. In the present study, we found that commercially available native and recombinant OPNs contain variable amounts of endotoxin (LPS) and that removal of endotoxin by polymyxin B-agarose column abrogated their cytokine-inducing activity. These results suggest the questionable evidence of the ability of OPN to induce several cytokines in human PBMCs and draw attention to the exquisite sensitivity of PBMCs/monocytes to endotoxin contaminants.
authors.affiliation: Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224, USA.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Konno
authors.forename: Takuya
authors.initials: T
authors.lastname: Hoshi
authors.forename: Toshio
authors.initials: T
authors.lastname: Taira
authors.forename: Beverly
authors.initials: B
authors.lastname: Plunkett
authors.forename: Shau-Ku
authors.initials: SK
authors.lastname: Huang
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis*; D004340:Drug Contamination; D004731:Endotoxins / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D018836:Inflammation Mediators / Q000378:metabolism; D018664:Interleukin-12 / Q000096:biosynthesis; D053762:Interleukin-12 Subunit p40; D015850:Interleukin-6 / Q000096:biosynthesis; D016209:Interleukin-8 / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000494:pharmacology; D051379:Mice; D053495:Osteopontin; D021122:Protein Subunits / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000494:pharmacology; D012795:Sialoglycoproteins / Q000302:isolation & purification / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D016207:Cytokines; D004731:Endotoxins; D018836:Inflammation Mediators; D053762:Interleukin-12 Subunit p40; D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D021122:Protein Subunits; D011994:Recombinant Proteins; C506895:SPP1 protein, human; D012795:Sialoglycoproteins; C506896:Spp1 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D053495:Osteopontin; D018664:Interleukin-12