title: Compatibility of superparamagnetic iron oxide nanoparticle labeling for ¹H MRI cell tracking with ³¹P MRS for bioenergetic measurements.
abstract: Labeling of cells with superparamagnetic iron oxide nanoparticles permits cell tracking by (1)H MRI while (31)P MRS allows non-invasive evaluation of cellular bioenergetics. We evaluated the compatibility of these two techniques by obtaining (31)P NMR spectra of iron-labeled and unlabeled immobilized C2C12 myoblast cells in vitro. Broadened but usable (31)P spectra were obtained and peak area ratios of resonances corresponding to intracellular metabolites showed no significant differences between labeled and unlabeled cell populations. We conclude that (31)P NMR spectra can be obtained from cells labeled with sufficient iron to permit visualization by (1)H imaging protocols and that these spectra have sufficient quality to be used to assess metabolic status. This result introduces the possibility of using localized (31)P MRS to evaluate the viability of iron-labeled therapeutic cells as well as surrounding host tissue in vivo.
authors.affiliation: Laboratory of Cardiovascular Science, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Zhuoli
authors.initials: Z
authors.lastname: Zhang
authors.forename: Brynne
authors.initials: B
authors.lastname: Hancock
authors.forename: Stephanie
authors.initials: S
authors.lastname: Leen
authors.forename: Sharan
authors.initials: S
authors.lastname: Ramaswamy
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Sollott
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Boheler
authors.forename: Magdalena
authors.initials: M
authors.lastname: Juhaszova
authors.forename: Edward G
authors.initials: EG
authors.lastname: Lakatta
authors.forename: Richard G
authors.initials: RG
authors.lastname: Spencer
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Fishbein
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D002470:Cell Survival; D058948:Cell Tracking / Q000379:methods*; D004734:Energy Metabolism / Q000502:physiology*; D005290:Ferric Compounds / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D051379:Mice; D032446:Myoblasts / Q000166:cytology* / Q000378:metabolism; D010477:Perfusion; D010759:Phosphorus Isotopes; D011522:Protons; D013194:Staining and Labeling
chemical_list: D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D010759:Phosphorus Isotopes; D011522:Protons; C000499:ferric oxide