title: Analysis of DNA Double-Strand Breaks and Cytotoxicity after 7 Tesla Magnetic Resonance Imaging of Isolated Human Lymphocytes.
abstract: The global use of magnetic resonance imaging (MRI) is constantly growing and the field strengths increasing. Yet, only little data about harmful biological effects caused by MRI exposure are available and published research analyzing the impact of MRI on DNA integrity reported controversial results. This in vitro study aimed to investigate the genotoxic and cytotoxic potential of 7 T ultra-high-field MRI on isolated human peripheral blood mononuclear cells. Hence, unstimulated mononuclear blood cells were exposed to 7 T static magnetic field alone or in combination with maximum permissible imaging gradients and radiofrequency pulses as well as to ionizing radiation during computed tomography and γ-ray exposure. DNA double-strand breaks were quantified by flow cytometry and automated microscopy analysis of immunofluorescence stained γH2AX. Cytotoxicity was studied by CellTiter-Blue viability assay and [3H]-thymidine proliferation assay. Exposure of unstimulated mononuclear blood cells to 7 T static magnetic field alone or combined with varying gradient magnetic fields and pulsed radiofrequency fields did not induce DNA double-strand breaks, whereas irradiation with X- and γ-rays led to a dose-dependent induction of γH2AX foci. The viability assay revealed a time- and dose-dependent decrease in metabolic activity only among samples exposed to γ-radiation. Further, there was no evidence for altered proliferation response after cells were exposed to 7 T MRI or low doses of ionizing radiation (≤ 0.2 Gy). These findings confirm the acceptance of MRI as a safe non-invasive diagnostic imaging tool, but whether MRI can induce other types of DNA lesions or DNA double-strand breaks during altered conditions still needs to be investigated.
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Reddig
authors.affiliation: Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Fatahi
authors.affiliation: Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Friebe
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Karina
authors.initials: K
authors.lastname: Guttek
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Hartig
authors.affiliation: Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Godenschweger
authors.affiliation: Medipan GmbH, Dahlewitz/Berlin, Germany; Faculty of Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Roggenbuck
authors.affiliation: Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Ricke
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Reinhold
authors.affiliation: Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany; German Center for Neurodegenerative Disease, Magdeburg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Speck
mesh_terms: D000328:Adult; D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation / Q000379:methods*; D002470:Cell Survival / Q000187:drug effects; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects; D005260:Female; D005434:Flow Cytometry; D006657:Histones / Q000378:metabolism; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology; D013936:Thymidine / Q000378:metabolism; D014316:Tritium / Q000378:metabolism
chemical_list: C468783:H2AX protein, human; D006657:Histones; D010835:Phytohemagglutinins; D014316:Tritium; D013936:Thymidine