title: Evaluation of the interactions between multiwalled carbon nanotubes and Caco-2 cells.
abstract: The aim of this study was to determine whether multiwalled carbon nanotubes (MWNCT) are taken up by and are toxic to human intestinal enterocytes using the Caco-2 cell model. Caco-2 cells were exposed to 50 μg/ml MWCNT (oxidized or pristine) for 24 h, and experiments were repeated in the presence of 2.5 mg/L natural organic matter. Cells displayed many of the properties that characterize enterocytes, such as apical microvilli, basolateral basement membrane, and glycogen. The cell monolayers also displayed tight junctions and electrical resistance. Exposure to pristine and oxidized MWCNT, with or without natural organic matter, did not markedly affect viability, which was assessed by measuring activity of released lactate dehydrogenase (LDH) and staining with propidium iodide. Ultrastructural analysis revealed some damage to microvilli colocalized with the MWCNT; however, neither type of MWCNT was taken up by Caco-2 cells. In contrast, pristine and oxidized MWCNT were taken up by the macrophage RAW 264.7 line. Our study suggests that intestinal enterocytes cells do not take up MWCNT.
authors: Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA.
authors: Katherine A
authors: KA
authors: Clark
authors: Cliona
authors: C
authors: O'Driscoll
authors: Carol A
authors: CA
authors: Cooke
authors: Bill A
authors: BA
authors: Smith
authors: Kevin
authors: K
authors: Wepasnick
authors: D Howard
authors: DH
authors: Fairbrother
authors: Peter S J
authors: PS
authors: Lees
authors: Joseph P
authors: JP
authors: Bressler
mesh_terms: D018938:Caco-2 Cells; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D020895:Enterocytes / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000737:chemistry / Q000633:toxicity* / Q000648:ultrastructure; D011419:Propidium / Q000737:chemistry; D019108:Tight Junctions / Q000187:drug effects; D013997:Time Factors
chemical_list: D037742:Nanotubes, Carbon; D011419:Propidium; D007770:L-Lactate Dehydrogenase