title: Enhanced stem cell tracking via electrostatically assembled fluorescent SPION-peptide complexes.
abstract: For cellular MRI there is a need to label cells with superparamagnetic iron oxide nanoparticles (SPION) that have multiple imaging moieties that are nontoxic and have increased NMR relaxation properties to improve the detection and tracking of therapeutic cells. Although increases in the relaxation properties of SPION have been accomplished, detection of tagged cells is limited by either poor cell labeling efficiency or low intracellular iron content. A strategy via a complex formation with transfection agents to overcome these obstacles has been reported. In this paper, we report a complex formation between negatively charged fluorescent monodisperse SPION and positively charged peptides and use the complex formation to improve the MR properties of labeled stem cells. As a result, labeled stem cells exhibited a strong fluorescent signal and enhanced T 2*-weighted MR imaging in vitro and in vivo in a flank tumor model.
authors: Frank Laboratory, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD 20892-1074, USA. leejaeho@mail.nih.gov
authors: Jae-Ho
authors: JH
authors: Lee
authors: Melissa A
authors: MA
authors: Smith
authors: Wei
authors: W
authors: Liu
authors: Eric M
authors: EM
authors: Gold
authors: Bobbi
authors: B
authors: Lewis
authors: Ho-Taek
authors: HT
authors: Song
authors: Joseph A
authors: JA
authors: Frank
mesh_terms: D000818:Animals; D002460:Cell Line; D002645:Chickens; D005290:Ferric Compounds / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D051379:Mice; D008856:Microscopy, Fluorescence; D010455:Peptides / Q000378:metabolism*; D019047:Phantoms, Imaging; D013194:Staining and Labeling; D055672:Static Electricity; D051598:Whole Body Imaging
chemical_list: D005290:Ferric Compounds; D010455:Peptides; C000499:ferric oxide; D007501:Iron