title: The influence of ferucarbotran on the chondrogenesis of human mesenchymal stem cells.
abstract: For in vivo applications of magnetically labeled stem cells, biological effects of the labeling procedure have to be precluded. This study evaluates the effect of different ferucarbotran cell labeling protocols on chondrogenic differentiation of human mesenchymal stem cells (hMSC) as well as their implications for MR imaging. hMSC were labeled with ferucarbotran using various protocols: cells were labeled with 100 microg Fe/ml for 4 and 18 h and additional samples were cultured for 6 or 12 days after the 18 h labeling. Supplementary samples were labeled by transfection with protamine sulfate. Iron uptake was quantified by ICP-spectrometry and labeled cells were investigated by transmission electron microscopy and by immunostaining for ferucarbotran. The differentiation potential of labeled cells was compared with unlabeled controls by staining with Alcian blue and Hematoxylin and Eosin, then quantified by measurements of glucosaminoglycans (GAG). Contrast agent effect at 3 T was investigated on days 1 and 14 of chondrogenic differentiation by measuring signal-to-noise ratios on T(2)-SE and T(2)*-GE sequences. Iron uptake was significant for all labeling protocols (p < 0.05). The uptake was highest after transfection with protamine sulfate (25.65 +/- 3.96 pg/cell) and lowest at an incubation time of 4 h without transfection (3.21 +/- 0.21 pg/cell). While chondrogenic differentiation was decreased using all labeling protocols, the decrease in GAG synthesis was not significant after labeling for 4 h without transfection. After labeling by simple incubation, chondrogenesis was found to be dose-dependent. MR imaging showed markedly lower SNR values of all labeled cells compared with the unlabeled controls. This contrast agent effect persisted for 14 days and the duration of differentiation. Magnetic labeling of hMSC with ferucarbotran inhibits chondrogenesis in a dose-dependent manner when using simple incubation techniques. When decreasing the incubation time to 4 h, inhibition of chondrogenesis was not significant.
authors: Department of Radiology, UCSF Medical Center, University of California, San Francisco, CA 94143-0628, USA.
authors: Tobias D
authors: TD
authors: Henning
authors: Elizabeth J
authors: EJ
authors: Sutton
authors: Anne
authors: A
authors: Kim
authors: Daniel
authors: D
authors: Golovko
authors: Andrew
authors: A
authors: Horvai
authors: Larry
authors: L
authors: Ackerman
authors: Barbara
authors: B
authors: Sennino
authors: Donald
authors: D
authors: McDonald
authors: Jeffrey
authors: J
authors: Lotz
authors: Heike E
authors: HE
authors: Daldrup-Link
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D020219:Chondrogenesis / Q000187:drug effects*; D003287:Contrast Media / Q000494:pharmacology*; D003911:Dextrans; D052203:Ferrosoferric Oxide / Q000494:pharmacology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects*; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; C065507:ferumoxides; D052203:Ferrosoferric Oxide