Exposure to radiation from single or combined radio frequencies provokes macrophage dysfunction in the RAW 264.7 cell line

Abstract

Purpose: The aim of this study was to determine whether exposure to radiation from single or multiple radio-frequency (RF) signals at 900 and 2450 MHz would induce effects in the RAW 264.7 cell line.

Materials and methods: Cell cultures were exposed to single or combined RF for 4, 24, 48, or 72 h in a GTEM electromagnetic test chamber. At the end of the radiation exposure time, viability and cell growth were analyzed by flow cytometry, nitric oxide (NO) production was measured by colorimetry, the expression of HSP70 and TNF-α was ascertained by qPCR, and the phagocytic activity was observed by microscopy.

Results: NO production increased after 48 h exposure at 2450 MHz, compared with controls. The group subjected to the combined interaction of two RFs showed an increase of HSP70 after 48 h exposure and a significant increase of NO and TNF-α after 72 h. The phagocytic activity of macrophages decreased in all groups as exposure time increased.

Conclusions: Our results indicated a decrease in phagocytic activity and an increase in inflammatory, cytoprotective, and cytotoxic responses in macrophages after continuous and combined exposure of multiple RF signals. Multiple RF interact in everyday life, the immune response in humans is unknown.

Graphical Abstract

Keywords:

• Combined radiofrequencies
• macrophage
• RAW 264.7

Acknowledgements

The authors wish to thank Rafael Fuentes and Rogelio Mirazo for their help and technical assistance.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was subsidized by the Spanish Ministry of Economy and Competitiveness through Project TEC2017-86110-R.

Notes on contributors

Alberto López-Furelos

Alberto López Furelos received the M.S. degree in Biotechnology from the University of Santiago de Compostela (USC) in 2012. He is currently pursuing the Ph.D. degree in medicine. His general research interests include biological effects of non-ionizing radiation.

Aarón A. Salas-Sánchez

Aarón Ángel Salas Sánchez completed his PhD in Physics from the USC in 2018. He is currently a Postdoctoral Fellow at USC. His general research interests include numerical methods in solving electromagnetic problems and array pattern synthesis.

Francisco J. Ares-Pena

Francisco José Ares Pena, Full Professor of Electromagnetics at University of Santiago de Compostela. He completed his PhD in physics from the USC and UCLA in 1993. He has authored more than 380 papers. He is fellow of IEEE “for contributions to antenna array pattern synthesis” since 2009. He is an associate editor of the journal “IEEE Transactions on Antennas and Propagation”.

José M. Leiro-Vidal

José Manuel Leiro Vidal completed his Ph.D. in Biology from USC, Spain, in 1987. He is a full professor in the Department of Parasitology. He has authored more than 174 research articles. His general research interests include the immunobiology of human and animal parasites, as well as the study of the antiparasitic and anti-inflammatory effect of products of natural origin.

Elena López-Martín

María Elena López Martín completed her PhD in medicine from USC, Spain, in 1999. She is an associate professor in human Anatomy in the Morphological Sciences Department in USC. She has authored, or co-authored a total of 103 papers. Since 2013 she is the Spanish Official Member of the Commission K (Electromagnetics in Biology and Medicine), URSI.