title: The use of gadolinium-carbon nanostructures to magnetically enhance stem cell retention for cellular cardiomyoplasty.
abstract: In this work, the effectiveness of using Gadonanotubes (GNTs) with an external magnetic field to improve retention of transplanted adult mesenchymal stem cells (MSCs) during cellular cardiomyoplasty was evaluated. As a high-performance T1-weighted magnetic resonance imaging (MRI) cell tracking label, the GNTs are gadolinium-loaded carbon nanotube capsules that render MSCs magnetic when internalized. MSCs were internally labeled with either superparamagnetic GNTs or colloidal diamagnetic lutetium (Lu). In vitro cell rolling assays and ex vivo cardiac perfusion experiments qualitatively demonstrated increased magnetic-assisted retention of GNT-labeled MSCs. Subsequent in vivo epicardial cell injections were performed around a 1.3 T NdFeB ring magnet sutured onto the left ventricle of female juvenile pigs (n = 21). Cell dosage, magnet exposure time, and endpoints were varied to evaluate the safety and efficacy of the proposed therapy. Quantification of retained cells in collected tissues by elemental analysis (Gd or Lu) showed that the external magnet helped retain nearly three times more GNT-labeled MSCs than Lu-labeled cells. The sutured magnet was tolerated for up to 168 h; however, an inflammatory response to the magnet was noted after 48 h. These proof-of-concept studies support the feasibility and value of using GNTs as a magnetic nanoparticle facilitator to improve cell retention during cellular cardiomyoplasty.
authors.affiliation: Department of Chemistry and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS-60, P.O. Box 1892, Houston, TX 77251-1892, USA.
authors.forename: Lesa A
authors.initials: LA
authors.lastname: Tran
authors.forename: Mayra
authors.initials: M
authors.lastname: Hernández-Rivera
authors.forename: Ari N
authors.initials: AN
authors.lastname: Berlin
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.forename: Luiz
authors.initials: L
authors.lastname: Sampaio
authors.forename: Christina
authors.initials: C
authors.lastname: Bové
authors.forename: Maria da Graça
authors.initials: Mda G
authors.lastname: Cabreira-Hansen
authors.forename: James T
authors.initials: JT
authors.lastname: Willerson
authors.forename: Emerson C
authors.initials: EC
authors.lastname: Perin
authors.forename: Lon J
authors.initials: LJ
authors.lastname: Wilson
mesh_terms: D000818:Animals; D018421:Cardiomyoplasty / Q000379:methods*; D058948:Cell Tracking; D002478:Cells, Cultured; D003287:Contrast Media / Q000737:chemistry; D023381:Endpoint Determination; D005260:Female; D005682:Gadolinium / Q000737:chemistry*; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013552:Swine
chemical_list: D003287:Contrast Media; D037742:Nanotubes, Carbon; D005682:Gadolinium
keywords: Cellular cardiomyoplasty; Gadonanotube; Mesenchymal stem cell; Nanotechnology; Single-walled carbon nanotube