Extremely low‐frequency electromagnetic fields affect the immune response of monocyte‐derived macrophages to pathogens

Abstract

This study aimed to determine the effect of extremely low-frequency electromagnetic fields (ELF-EMF) on the physiological response of phagocytes to an infectious agent. THP-1 cells (human monocytic leukemia cell line) were cultured and 50 Hz, 1 mT EMF was applied for 4-6 h to cells induced with Staphylococcus aureus or interferon gamma/lipopolysaccharide (IFγ/LPS). Alterations in nitric oxide (NO), inducible nitric oxide synthase (iNOS) levels, heat shock protein 70 levels (hsp70), cGMP levels, caspase-9 activation, and the growth rate of S. aureus were determined. The growth curve of exposed bacteria was lower than the control. Field application increased NO levels. The increase was more prominent for S. aureus-induced cells and appeared earlier than the increase in cells without field application. However, a slight decrease was observed in iNOS levels. Increased cGMP levels in response to field application were closely correlated with increased NO levels. ELF-EMF alone caused increased hsp70 levels in a time-dependent manner. When cells were induced with S. aureus or IFγ/LPS, field application produced higher levels of hsp70. ELF-EMF suppressed caspase-9 activation by a small extent. These data confirm that ELF-EMF affects bacterial growth and the response of the immune system to bacterial challenges, suggesting that ELF-EMF could be exploited for beneficial uses.

Low‐frequency electromagnetic fields do not alter responses of inflammatory genes and proteins in human monocytes and immune cell lines

“…In these studies, the experimental setup and exposure conditions differed strongly from our study, but all studies used a 50 Hz signal. Interestingly, other immune cell-related responses were found to be modulated by 50 Hz LF EMF, including reactive oxygen species production in macrophages [Akan et al, 2010;Frahm et al, 2010]. The differences in the findings between these studies and our study can partially be explained by our use of 5 mT signals, compared to the milliTesla (mT) ranges most studies employ.…”

“…Their potential harmful effects on biological systems, such as leukemia, breast cancer, and cardiovascular disease, are under constant debate [Ahlbom et al, 2008]. In contrast, beneficial effects of LF EMF have been reported, including decreased severity of intestinal lesions in coccidian-infected chickens , accelerated wound healing [Callaghan et al, 2008;Goudarzi et al, 2010] and accelerated bone healing in rats and humans [Grana et al, 2008;Griffin et al, 2008], and augmented response of macrophages to bacterial challenges in humans [Akan et al, 2010]. To date, no mechanism of action has been elucidated, although several possible mechanisms have been suggested, including changes in signal transduction pathways and modulation of oxygen radicals [Liburdy et al, 1993;Blank and Soo 2001;Rollwitz et al, 2004;Frahm et al, 2010].…”

Electromagnetic Waves and Human Health

“…When cells were induced with S. aureus or IFγ/LPS, field application produced higher levels of hsp70, and suppressed the caspase-9 activation. These data showed that ELF-EMF affect the response of immune system, which suggests that it can be considered for beneficial uses (37). Another hypothesis of effects related with ELF-EMF is that it changes the free radical levels in the organism.…”

Quasi-optical Systems Based on Periodic Structures

“…In this case, linearly increasing distribution reduces the reflected power much more than the other distribution functions up to 33 GHz. [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] GHz range, sinusoidal and linearly decreasing functions are more useful in terms of small reflection. Fig.…”