title: Transport of dendrimer nanocarriers through epithelial cells via the transcellular route.
abstract: The mechanism of transport of G3 PAMAM and surface-modified (with lauroyl chains) G3 PAMAM dendrimer nanocarriers across Caco-2 cell monolayers has been investigated. Flow-cytometry studies following quenching of extracellular fluorescence demonstrated the cellular internalisation of dendrimers. Optical sectioning of cells incubated with fluorescein isothiocyanate (FITC)-conjugated dendrimer and lauroyl-dendrimer using confocal laser scanning microscopy revealed colocalisation of a marker for cell nuclei (4',6-diamidino-2-phenylindole, DAPI) and FITC fluorescence, also suggesting cellular internalisation of dendrimers. Transmission electron microscopic analyses of cells incubated with gold-labelled G3 PAMAM dendrimers confirmed endocytosis-mediated cellular internalisation when dendrimers were applied to the apical domain of Caco-2 cells. These findings are in agreement with our previous studies using Caco-2 cell monolayers that showed a significant decrease of dendrimer uptake in the presence of colchicine (endocytosis inhibitor) and when temperature was reduced from 37 to 4 degrees C.
authors.affiliation: School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
authors.forename: Rachaneekorn
authors.initials: R
authors.lastname: Jevprasesphant
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Penny
authors.forename: David
authors.initials: D
authors.lastname: Attwood
authors.forename: Antony
authors.initials: A
authors.lastname: D'Emanuele
mesh_terms: D001692:Biological Transport; D018938:Caco-2 Cells; D050091:Dendrimers; D004337:Drug Carriers / Q000493:pharmacokinetics*; D004705:Endocytosis; D004847:Epithelial Cells / Q000378:metabolism*; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006801:Humans; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures; D010539:Permeability; D011073:Polyamines / Q000493:pharmacokinetics*; D014343:Trypan Blue
chemical_list: D050091:Dendrimers; D004337:Drug Carriers; D005456:Fluorescent Dyes; C104700:PAMAM Starburst; D011073:Polyamines; D016650:Fluorescein-5-isothiocyanate; D014343:Trypan Blue