title: Biological effects of double-walled carbon nanotubes on the innate immune system: An in vitro study on THP-1 human monocytes.
abstract: DWCNTs have numerous industrial and biomedical applications and several studies reported that they could act as immunomodulator systems. The immune system is the first line of defence of the human body when exposed to particulate matter. In order to investigate DWCNTs' role on innate immunity, we used THP-1 monocytic cells for the purpose of this study. We showed that DWCNTs were not cytotoxic until 6h, 24h, 48h and 72h of incubation with THP-1 monocytic cells (concentrations tested from 10 to 50μg/mL). From 6h to 72h of incubation of THP-1 cells with DWCNTs, we measured a significant increase of the baseline cell index using xCELLigence(®) technology showing cell adhesion. After 24h of exposure, DWCNTs agglomerates were localized in THP-1 monocyte cytoplasm and cell adhesion was observed simultaneously with a significant increase in the expression of CD11b and CD14 cell surface proteins. Pro-inflammatory cytokine secretion (IL-1β, IL-6, IL-8, TNF-α and IL-10) was also measured in supernatants after 6h or 24h of exposure to DWCNTs. This pro-inflammatory response was increased in THP-1 monocytic cells pre-treated with LPS. Altogether, our data indicate that DWCNTs induce an increased pro-inflammatory response of THP-1 monocytes and seem to modulate cell surface protein expression confirming that DWCNTs could act as stimulators of innate immunity.
authors.affiliation: Institut de Recherche Biomédicale des Armées (IRBA), Département EBR/Unité des Risques Technologiques Emergents, 1, place du Général Valérie André, BP73, 91223 Brétigny-sur-Orge Cedex, France. Electronic address: samir.dekali@gmail.com.
authors.forename: Samir
authors.initials: S
authors.lastname: Dekali
authors.affiliation: Institut de Recherche Biomédicale des Armées (IRBA), Département EBR/Unité des Risques Technologiques Emergents, 1, place du Général Valérie André, BP73, 91223 Brétigny-sur-Orge Cedex, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Bachelet
authors.affiliation: Institut de Recherche Biomédicale des Armées (IRBA), Département EBR/Unité des Risques Technologiques Emergents, 1, place du Général Valérie André, BP73, 91223 Brétigny-sur-Orge Cedex, France.
authors.forename: Séverine
authors.initials: S
authors.lastname: Maunoir-Regimbal
authors.affiliation: CIRIMAT, Université de Toulouse, CNRS, INPT, UPS, UMR CNRS-UPS-INP No. 5085, Université Toulouse 3 Paul Sabatier, Bât. CIRIMAT, 118, route de Narbonne, 31062 Toulouse Cedex 9, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Flahaut
authors.affiliation: Institut de Recherche Biomédicale des Armées (IRBA), Département EBR/Unité des Risques Technologiques Emergents, 1, place du Général Valérie André, BP73, 91223 Brétigny-sur-Orge Cedex, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Debouzy
authors.affiliation: Institut de Recherche Biomédicale des Armées (IRBA), Département EBR/Unité des Risques Technologiques Emergents, 1, place du Général Valérie André, BP73, 91223 Brétigny-sur-Orge Cedex, France.
authors.forename: David
authors.initials: D
authors.lastname: Crouzier
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D007155:Immunologic Factors / Q000494:pharmacology*; D008565:Membrane Proteins / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects*; D037742:Nanotubes, Carbon / Q000737:chemistry*
chemical_list: D016207:Cytokines; D007155:Immunologic Factors; D008565:Membrane Proteins; D037742:Nanotubes, Carbon
keywords: Double-walled carbon nanotubes; Inflammation; Innate immunity; LPS; THP-1 monocytes