title: Effects of supermagnetic iron oxide labeling on the major functional properties of human mesenchymal stem cells from multiple sclerosis patients.
abstract: OBJECTIVE
  In the last few years, treatment protocols using mesenchymal stem cells (MSC) in various experimental models and human diseases have been investigated. MSCs are on the focus of stem cell research, since they are considered as a type of adult stem cells with low toxicity and acceptable side effects profile and they can be administered autologously. In addition several studies have revealed significant immunomodulatory properties of MSCs and a potential for transdifferentiation, including neural differentiation, both in vivo and in vitro. Magnetic resonance imaging (MRI) is a non-invasive technique that can be used to track labeled cells and evaluate their migration ability in various clinical settings.
  
  
  RESULTS
  In this study we investigated whether such labeling of MSCs with the commercially used para-magnetic material, Feridex, has any negative effect on the above mentioned functional properties of MSCs. We labeled human mesenchymal stem cells (hMSC) with poly-L-lysine coated Feridex(®) and evaluated their cellular differentiation and immunomodulatory properties, in vitro. In comparison with unlabeled cells, labeled hMSC exhibited normal adipogenic and osteogenic differentiation, but decreased chondrogenic differentiation. Regarding neural differentiation, labeled and unlabeled cells were similar in their ability to express neural-like and glial like surface proteins. Finally, both labeled and unlabeled MSCs exhibited a dose-dependent, significant blocking effect on the proliferation of healthy donors lymphocytes following mitogen stimulation.
  
  
  CONCLUSIONS
  These findings indicate that labeling with Feridex does not affect the immunomodulatory, nor the neural transdifferentiation potential of MScs and therefore, Feridex may be used for the tracking of this type of stem cells in clinical applications, without compromising their major functional properties.
authors.affiliation: Department of Neurology, Laboratory of Neuroimmunology and Agnes Ginges Center for Neurogenetics and Multiple Sclerosis Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Kassis
authors.affiliation: Department of Neurology, Laboratory of Neuroimmunology and Agnes Ginges Center for Neurogenetics and Multiple Sclerosis Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Vaknin-Dembinsky
authors.affiliation: National Institute of Sciences, Bethesda, USA.
authors.forename: Jeff
authors.initials: J
authors.lastname: Bulte
authors.affiliation: Department of Neurology, Laboratory of Neuroimmunology and Agnes Ginges Center for Neurogenetics and Multiple Sclerosis Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Karussis
keywords: Feridex; Human mesenchymal stem cells; Immunomodulation; differentiation