Exposure to a MRI‐type high‐strength static magnetic field stimulates megakaryocytic/erythroid hematopoiesis in CD34⁺ cells from human placental and umbilical cord blood

Abstract

The biological response after exposure to a high-strength static magnetic field (SMF) has recently been widely discussed from the perspective of possible health benefits as well as potential adverse effects. To clarify this issue, CD34+ cells from human placental and umbilical cord blood were exposed under conditions of high-strength SMF in vitro. The high-strength SMF exposure system was comprised of a magnetic field generator with a helium-free superconducting magnet with built-in CO2 incubator. Freshly prepared CD34 cells were exposed to a 5 tesla (T) SMF with the strongest magnetic field gradient (41.7 T/m) or a 10 T SMF without magnetic field gradient for 4 or 16 h. In the harvested cells after exposure to 10 T SMF for 16 h, a significant increase of hematopoietic progenitors in the total burst-forming unit erythroid- and megakaryocytic progenitor cells-derived colony formation was observed, thus producing 1.72- and 1.77-fold higher than the control, respectively. Furthermore, early hematopoiesis-related and cell cycle-related genes were found to be significantly up-regulated by exposure to SMF. These results suggest that the 10 T SMF exposure may change gene expressions and result in the specific enhancement of megakaryocytic/erythroid progenitor (MEP) differentiation from pluripotent hematopoietic stem cells and/or the proliferation of bipotent MEP.

Functional investigations on human mesenchymal stem cells exposed to magnetic fields and labeled with clinically approved iron nanoparticles

“…Moreover, magnetic-fluid-loaded liposomes were guided to the near vicinity of human adenocarcinoma prostatic cells by means of a 0.29-T external magnet [25]. Except for sporadic reports on the influence of magnetic fields on hematopoietic progenitor cells [26], neural progenitor cells [27] and myoblasts [28] to date no report exists investigating on possible effects of magnetic fields on iron-labeled and unlabeled human stem cells. In this study an innovative labeling protocol for tracking MSCs by MRI using SPIO in combination with magnetic fields was established.…”

Effects of exposure to gradient magnetic fields emitted by nuclear magnetic resonance devices on clonogenic potential and proliferation of human hematopoietic stem cells

“…Effects of 1.5 T and 3 T‐exposure protocols were consistently and reproducibly seen in all independent experiments performed (three samples for each GMF protocol used with experiments performed at least in duplicate). Interestingly, a previous study has shown that proliferation and differentiation of human CD34+ from human placental and umbilical cord blood were both affected by exposure to 10 T static magnetic field [Monzen et al, ]. In particular, authors showed that after 16 h exposure there was significant increase of BFU‐E and this effect was accompanied by a significant up‐regulation of cell cycle‐related genes and genes involved in early‐hematopoiesis such as c‐KIT , GATA2 , and RUNX1 .…”

“…As such, EMFs have been suggested as promising tools to positively influence different steps of neurogenic and osteogenic processes [Boyette and Herrera‐Soto, ; Bai et al, ; Di Lazzaro et al, ; Ongaro et al, ; Podda et al, ; Leone et al, , ]. On the other hand, epidemiological reports, although controversial, suggest a possible association between exposure to EMF and frequency of childhood leukemia [IARC, ; Calvente et al, ] thus prompting studies evaluating effects of EFs on human hematopoietic stem/progenitor cells [Nafziger et al, ; Reipert et al, ; Monzen et al, ].…”

Effects of 7 T static magnetic fields on the expression of biological markers and the formation of bone in rats

“…The authors showed that 3 T SMF exposure alone neither affected the expression of 498 proteins/genes from human embryonic lung fibroblasts (Hel 299 cells) [Schwenzer et al, ] nor induced double‐stranded breaks in human promyelocytic leukemia cells (HL‐60 cells) or CD34+ human acute myeloid leukemia cells (KG‐1a cells) [Schwenzer et al, ]. However, when cells were exposed to strong SMFs with a field gradient, several studies reported biological effects caused by exposure [Hirose et al, ; Sakurai et al, , 2009; Monzen et al, ]. In particular, Monzen et al [] examined the effects of SMF with a high gradient (41.7 T/m) or a 10 T SMF without a magnetic field gradient for 4 or 16 h on CD34+ cells and showed that the magnetic field gradient played an important role in upregulating megakaryocytic/erythroid hematopoiesis in CD34+ cells.…”

“…However, when cells were exposed to strong SMFs with a field gradient, several studies reported biological effects caused by exposure [Hirose et al, ; Sakurai et al, , 2009; Monzen et al, ]. In particular, Monzen et al [] examined the effects of SMF with a high gradient (41.7 T/m) or a 10 T SMF without a magnetic field gradient for 4 or 16 h on CD34+ cells and showed that the magnetic field gradient played an important role in upregulating megakaryocytic/erythroid hematopoiesis in CD34+ cells. Repeated studies using different cell lines (HL‐60 cells [Hirose et al, ], osteoblasts [Sakurai et al, ], and insulin‐secreting cells [Sakurai et al, ]) have been conducted by the same group.…”