title: An organotypical in vitro model of the liver parenchyma for uptake studies of diagnostic MR receptor agents.
abstract: Testing of receptor-specific MR contrast agents targeted to the liver is hampered by a shortage of viable in vitro models with in vivo-like hepatocellular morphology. Coated pits are ultrastructural signs of an active receptor mediated endocytosis in hepatocytes. Expression of coated pits by matrix overlaid hepatocytes was studied by transmission electron microscopy. Binding of a rhodaminated asialoglycoprotein receptor agent (MION-ASF-rh) was assessed by fluorescence microscopy. Fluorescence of cells exposed to MION-ASF-rh with D(+)-galactose reduced fluorescent light emission to a level of 58% of MION-ASF-rh-induced fluorescence. After preincubation with the hepatotoxin CCl4 a dose-dependent decrease in fluorescent light emission resulted. Hepatocytes maintained a homogeneous cell surface expression, with microprojections, coated pits, and vesicles on both sinusoidal surfaces. Matrix overlaid primary hepatocytes constitute a viable, morphologically and functionally differentiated model. This model can be used to study receptor binding, uptake, and blockage of diagnostic magnetopharmaceuticals under controlled conditions.
authors.affiliation: Institute for General Pharmacology, Medizinische Hochschule Hannover, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bader
authors.forename: P
authors.initials: P
authors.lastname: Reimer
authors.forename: E
authors.initials: E
authors.lastname: Knop
authors.forename: K
authors.initials: K
authors.lastname: Böker
authors.forename: U
authors.initials: U
authors.lastname: Christians
authors.forename: R
authors.initials: R
authors.lastname: Weissleder
authors.forename: K F
authors.initials: KF
authors.lastname: Sewing
mesh_terms: D000818:Animals; D037263:Asialoglycoprotein Receptor; D001212:Asialoglycoproteins / Q000378:metabolism* / Q000493:pharmacokinetics; D002478:Cells, Cultured; D003287:Contrast Media; D005260:Female; D005290:Ferric Compounds / Q000493:pharmacokinetics; D052203:Ferrosoferric Oxide; D060748:Fetuins; D007501:Iron / Q000493:pharmacokinetics; D008099:Liver / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008279:Magnetic Resonance Imaging; D008854:Microscopy, Electron; D010087:Oxides / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012235:Rhodamines / Q000493:pharmacokinetics; D000509:alpha-Fetoproteins / Q000493:pharmacokinetics
chemical_list: D037263:Asialoglycoprotein Receptor; D001212:Asialoglycoproteins; D003287:Contrast Media; D005290:Ferric Compounds; D060748:Fetuins; D010087:Oxides; D011956:Receptors, Cell Surface; D012235:Rhodamines; D000509:alpha-Fetoproteins; C017029:asialofetuin; C027755:rhodamine isothiocyanate; D007501:Iron; D052203:Ferrosoferric Oxide