title: Tracking T-cells in vivo with a new nano-sized MRI contrast agent.
abstract: Non-invasive in vivo tracking of T-cells by magnetic resonance imaging (MRI) can lead to a better understanding of many pathophysiological situations, including AIDS, cancer, diabetes, graft rejection. However, an efficient MRI contrast agent and a reliable technique to track non-phagocytic T-cells are needed. We report a novel superparamagnetic nano-sized iron-oxide particle, IOPC-NH2 series particles, coated with polyethylene glycol (PEG), with high transverse relaxivity (250 s(-1) mM(-1)), thus useful for MRI studies. IOPC-NH2 particles are the first reported magnetic particles that can label rat and human T-cells with over 90% efficiency, without using transfection agents, HIV-1 transactivator peptide, or electroporation. IOPC-NH2 particles do not cause any measurable effects on T-cell properties. Infiltration of IOPC-NH2-labeled T-cells can be detected in a rat model of heart-lung transplantation by in vivo MRI. IOPC-NH2 is potentially valuable contrast agents for labeling a variety of cells for basic and clinical cellular MRI studies, e.g., cellular therapy.
  
  
  BACKGROUND
  In this study, a novel PEG coated superparamagnetic nano-sized iron-oxide particle was investigated as a T-cell labeling agent for MRI studies. The reported particles can label T-cells with over 90% efficiency, without using transfection agents, HIV-1 transactivator peptide, or electroporation, therefore may enable more convenient preclinical call labeling studies.
authors.affiliation: Pittsburgh NMR Center for Biomedical Research and Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Qing
authors.initials: Q
authors.lastname: Ye
authors.forename: Yijen
authors.initials: Y
authors.lastname: Wu
authors.forename: Wen-Yuan
authors.initials: WY
authors.lastname: Hsieh
authors.forename: Chih-Lung
authors.initials: CL
authors.lastname: Chen
authors.forename: Hsin-Hsin
authors.initials: HH
authors.lastname: Shen
authors.forename: Shian-Jy
authors.initials: SJ
authors.lastname: Wang
authors.forename: Haosen
authors.initials: H
authors.lastname: Zhang
authors.forename: T Kevin
authors.initials: TK
authors.lastname: Hitchens
authors.forename: Chien
authors.initials: C
authors.lastname: Ho
mesh_terms: D000818:Animals; D058948:Cell Tracking; D003287:Contrast Media; D005290:Ferric Compounds / Q000737:chemistry*; D016041:Heart-Lung Transplantation; D006801:Humans; D019169:Jurkat Cells; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008297:Male; D011092:Polyethylene Glycols / Q000737:chemistry; D011859:Radiography; D051381:Rats; D044968:Regenerative Medicine; D013601:T-Lymphocytes / Q000166:cytology / Q000000981:diagnostic imaging
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide; D011092:Polyethylene Glycols