Evaluation of the Effects of Power‐Frequency Magnetic Field Exposure on B‐Cell Differentiation From Human Hematopoietic Stem/Progenitor Cells

Abstract

The causal relationship between exposure to power‐frequency magnetic fields (MFs) and childhood leukemia has long been controversial. The most common type of childhood leukemia is acute B‐lymphoblastic leukemia caused by abnormal proliferation of B cells in the early differentiation process. Here, we focused on B‐cell early differentiation and aimed to evaluate the effects of exposing cells to power‐frequency MF. First, we optimized an in vitro differentiation protocol of human hematopoietic stem/progenitor cells (HSPCs) to B‐cell lineages. Following validation of the responsiveness of the protocol to additional stimulations and the uniformity of the experimental conditions, human HSPCs were continuously exposed to 300 mT of 50 Hz MF for 35 days of the differentiation process. These experiments were performed in a blinded manner. The percentages of myeloid or lymphoid cells and their degree of differentiation from pro‐B to immature‐B cells in the MF‐exposed group showed no significant changes compared with those in the control group. Furthermore, the expression levels of recombination‐activating gene (RAG)1 and RAG2 in the B cells were also similar to those in the control group. These results indicate that exposure to 50 Hz MF at 300 mT does not affect the human B‐cell early differentiation from HSPCs. © 2023 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.

Biological Effects of Magnetic Storms and ELF Magnetic Fields

“…Pulsed mode ELF-MF f (50)b(1 mT) on/off 5 min/10 min during 24 h induced single-and double-stranded DNA breaks in human diploid fibroblast cells [337]. At the same time, the genotoxic effects of MF are not observed in other studies with a continuous mode of MF generation [173,338].…”

“…The effects of ELF-MFs on cell differentiation are highly dependent on cell type. For example, the ELF-MF f (1-50)b(100-300)B(4.1)t(7-35 days) did not affect the differentiation of human pluripotent immune cells into either granulocytic or lymphocytic types [172,173]. The effect on differentiation may depend on the magnitude of induction of the permanent ELF-MF component [169,172,173].…”

“…For example, the ELF-MF f (1-50)b(100-300)B(4.1)t(7-35 days) did not affect the differentiation of human pluripotent immune cells into either granulocytic or lymphocytic types [172,173]. The effect on differentiation may depend on the magnitude of induction of the permanent ELF-MF component [169,172,173]. The ELF-MF f (50)b(0.4)B(18.5)t(30 min) influenced intracellular signaling by accelerating the clusterization of the epidermal growth factor receptor (EGFR) like a ligand and triggering the Ras small G-protein signaling cascade [174].…”