Original paper Cell manufacturing tracking and monitoring| Volume 15, ISSUE 3, P384-390, March 2013

Hematopoietic stem cell (CD34+) uptake of superparamagnetic iron oxide is enhanced by but not dependent on a transfection agent


      Background aims

      Tracking the fate of cells after infusion would be a valuable asset for many stem cell therapies, but very few (cell) labels are approved for human therapeutic use. Superparamagnetic iron oxide particles (SPIO) can be internalized into stem cells in vitro to allow real-time tracking with gradient echo magnetic resonance imaging, but SPIO are approved for (diagnostic) imaging and not for (therapeutic) cell labeling in vivo. In this study, we investigated the possibility of labeling stem cells with an SPIO approved for patient use, albeit in a novel manner by enhancing uptake with the use of a transfection agent, also approved for patient use. Although there are many reports of hematopoietic stem cells being labeled with SPIO, there is some controversy regarding the efficiency of this and whether undifferentiated CD34+ progenitor (stem) cells are able to take up iron in the absence of a transfection agent to enhance the process.


      Human CD34+ cells were treated in vitro as follows: incubation with (i) medium only (control), (ii) ferumoxide (Endorem) and (iii) ferumoxide (Endorem) plus exposure to a transfection agent (protamine sulfate). Cells were incubated for 2, 4 and 24 hours and assessed for viability, differentiation capacity and visualized in vitro with 3-T magnetic resonance imaging. The cells were also analyzed by means of flow cytometry and morphology examined by electron microscopy.


      CD34+ hematopoietic progenitor cells can internalize ferumoxide (Endorem) independently of a transfection agent. However, uptake of ferumoxide is enhanced after exposure to protamine sulfate. Iron labeling of CD34+ cells in this manner does not affect cell viability and does not appear to affect the potential of the cells to grow in culture. Iron-labeled CD34+ cells can be visualized in vitro on 3-T magnetic resonance image scanning.


      Endorem and protamine sulfate can be combined to promote iron oxide nanoparticle uptake by CD34+ cells, and this methodology can potentially be used to track the fate of cells in a clinical trial setting because both compounds are (separately) approved for clinical use.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Cytotherapy
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Freed C.R.
        • Greene P.E.
        • Breeze R.E.
        • Tsai W.Y.
        • DuMouchel W.
        • Kao R.
        • et al.
        Transplantation of embryonic dopamine neurons for severe Parkinson's disease.
        N Engl J Med. 2001; 344: 710-719
        • Mancardi G.
        • Saccardi R.
        Autologous hematopoietic stem-cell transplantation in multiple sclerosis.
        Lancet Neurol. 2008; 7: 626-636
        • Pal R.
        • Venkataramana N.K.
        • Bansal A.
        • Balaraju S.
        • Jan M.
        • Chandra R.
        • et al.
        Ex vivo-expanded autologous bone marrow-derived mesenchymal stromal cells in human spinal cord injury/paraplegia: a pilot clinical study.
        Cytotherapy. 2009; 11: 897-911
        • Plewka M.
        • Krzeminska-Pakula M.
        • Lipiec P.
        • Peruga J.Z.
        • Jezewski T.
        • Kidawa M.
        • et al.
        Effect of intracoronary injection of mononuclear bone marrow stem cells on left ventricular function in patients with acute myocardial infarction.
        Am J Cardiol. 2009; 104: 1336-1342
        • Kondziolka D.
        • Steinberg G.K.
        • Wechsler L.
        • Meltzer C.C.
        • Elder E.
        • Gebel J.
        • et al.
        Neurotransplantation for patients with subcortical motor stroke: a phase 2 randomized trial.
        J Neurosurg. 2005; 103: 38-45
        • England T.J.
        • Abaei M.
        • Auer D.P.
        • Lowe J.
        • Jones D.R.
        • Sare G.
        • et al.
        Granulocyte-colony stimulating factor for mobilizing bone marrow stem cells in subacute stroke: the stem cell trial of recovery enhancement after stroke 2 randomized controlled trial.
        Stroke. 2012; 43: 405-411
        • Daldrup-Link H.E.
        • Rudelius M.
        • Oostendorp R.A.
        • Jacobs V.R.
        • Simon G.H.
        • Gooding C.
        • et al.
        Comparison of iron oxide labeling properties of hematopoietic progenitor cells from umbilical cord blood and from peripheral blood for subsequent in vivo tracking in a xenotransplant mouse model XXX.
        Acad Radiol. 2005; 12: 502-510
        • Daldrup-Link H.E.
        • Rudelius M.
        • Oostendorp R.A.
        • Settles M.
        • Piontek G.
        • Metz S.
        • et al.
        Targeting of hematopoietic progenitor cells with MR contrast agents.
        Radiology. 2003; 228: 760-767
        • Arbab A.S.
        • Yocum G.T.
        • Kalish H.
        • Jordan E.K.
        • Anderson S.A.
        • Khakoo A.Y.
        • et al.
        Efficient magnetic cell labeling with protamine sulfate complexed to ferumoxides for cellular MRI.
        Blood. 2004; 104: 1217-1223
        • Arbab A.S.
        • Yocum G.T.
        • Rad A.M.
        • Khakoo A.Y.
        • Fellowes V.
        • Read E.J.
        • et al.
        Labeling of cells with ferumoxides-protamine sulfate complexes does not inhibit function or differentiation capacity of hematopoietic or mesenchymal stem cells.
        NMR Biomed. 2005; 18: 553-559
        • Jiang Q.
        • Zhang Z.G.
        • Ding G.L.
        • Silver B.
        • Zhang L.
        • Meng H.
        • et al.
        MRI detects white matter reorganization after neural progenitor cell treatment of stroke.
        Neuroimage. 2006; 32: 1080-1089
        • Guzman R.
        • Bliss T.
        • De Los Angeles A.
        • Moseley M.
        • Palmer T.
        • Steinberg G.
        Neural progenitor cells transplanted into the uninjured brain undergo targeted migration after stroke onset.
        J Neurosci Res. 2008; 86: 873-882
        • Guzman R.
        • Uchida N.
        • Bliss T.M.
        • He D.
        • Christopherson K.K.
        • Stellwagen D.
        • et al.
        Long-term monitoring of transplanted human neural stem cells in developmental and pathological contexts with MRI.
        Proc Natl Acad Sci U S A. 2007; 104: 10211-10216
        • Reimer P.
        • Tombach B.
        Hepatic MRI with SPIO: detection and characterization of focal liver lesions.
        Eur Radiol. 1998; 8: 1198-1204
        • Bull B.S.
        • Huse W.M.
        • Brauer F.S.
        • Korpman R.A.
        Heparin therapy during extracorporeal circulation, II: the use of a dose-response curve to individualize heparin and protamine dosage.
        J Thorac Cardiovasc Surg. 1975; 69: 685-689
        • Akbari A.A.
        • Mozdarani H.
        • Akhlaghpoor S.
        • Pourfatollah A.A.
        • Soleimani M.
        Evaluation of the homing of human CD34+ cells in mouse bone marrow using clinical MR imaging.
        Pak J Biol Sci. 2007; 10: 833-842
        • Daldrup-Link H.E.
        • Rudelius M.
        • Piontek G.
        • Metz S.
        • Brauer R.
        • Debus G.
        • et al.
        Migration of iron oxide-labeled human hematopoietic progenitor cells in a mouse model: in vivo monitoring with 1.5-T MR imaging equipment.
        Radiology. 2005; 234: 197-205
        • Niemeyer M.
        • Oostendorp R.A.
        • Kremer M.
        • Hippauf S.
        • Jacobs V.R.
        • Baurecht H.
        • et al.
        Non-invasive tracking of human haemopoietic CD34(+) stem cells in vivo in immunodeficient mice by using magnetic resonance imaging.
        Eur Radiol. 2010; 20: 2184-2193
        • Nohroudi K.
        • Arnhold S.
        • Berhorn T.
        • Addicks K.
        • Hoehn M.
        • Himmelreich U.
        In vivo MRI stem cell tracking requires balancing of detection limit and cell viability.
        Cell Transplant. 2010; 19: 431-441
        • Farrell E.
        • Wielopolski P.
        • Pavljasevic P.
        • van Tiel S.
        • Jahr H.
        • Verhaar J.
        • et al.
        Effects of iron oxide incorporation for long term cell tracking on MSC differentiation in vitro and in vivo.
        Biochem Biophys Res Commun. 2008; 369: 1076-1081
        • Janic B.
        • Rad A.M.
        • Jordan E.K.
        • Iskander A.S.
        • Ali M.M.
        • Varma N.R.
        • et al.
        Optimization and validation of Fe-Pro cell labeling method.
        PLoS One. 2009; 4: e5873