ID Number		927
Study Type		In Vivo
Model		10, 26, 2500 MHz (CW) exposure to mice and analysis of immune parameters
Details		C57BL/6 (H-2(b)) and BALB/c (H-2(d)) mice were exposed to 26 MHz RF at 5.6 W/kg at multiple 3 hour intervals. Exposure increased core temperature up to 2 degrees and resulted in a significant decrease in circulating lymphocytes and neutrophils as well as an increase in splenic T- and B- cells. Multiple exposures also decreased thymic weight, thymic and spleen cell density, and suppressed cell-mediated immune response. Non-RF heating had similar effects, but did not affect delayed hypersensitivity activity. Corticosteriod levels increased suggesting a level of stress following single and multiple exposures. In a subsequent study, mice were exposed to 2.6 GHz at SARs of 2.8 or 19 W/kg for 1 hour. Labeled lymphocyte migration from the lung to the spleen was decreased and migration to the bone marrow was increased by either RF exposure or steroid treatments. In an earlier study, 26 MHz exposure to mice for 4-7 minutes sufficient to increase body temperature 2-4 degrees was found to decrease circulating lymphocytes as well as decrease delayed hypersensitivity activity inflammation in the footpad of mice injected with Sheep RBCs. In another study, Balb/C mice were injected with EL-4 cells following a 10 minute exposure to 2.6 GHz (CW) RF sufficient to result in a 1.5°C increase in temperature. MW induced hyperthermia delayed the rejection of the allograft cells, while MW exposure at non-thermal levels had no effect. The authors suggest MW induced hyperthermia results in stress related steroid release resulting in immunosuppression. In subsequent studies, human serum was exposed to 10 MHz (CW) RF for ~ 6 hours at an SAR of 0.134 W/kg during Sephadex G-200 chromatography. Exposure resulted in an accelerated elution of the IgM, IgA and IgG fractions. Similarly, exposure of mouse spleen cells to 2.5 GHz (CW) RF for 15 minutes at an SAR of 0.117 W/kg during Sepharose 6MB chromatography resulted in a similar accelerated elution of Ig+ B-cells. The authors suggest a non-thermal MW-induced shape change in Ig proteins.
Findings		Effects
Status		Completed With Publication
Principal Investigator		University California Berkeley, USA - robert.liburdy@ucberkeley.edu
Funding Agency		Private/Instit.
Country		UNITED STATES
References		Liburdy, RP et al. Int. J. Radiat. Biol., (1984) 46:67-81 Liburdy, RP Radiat. Res., (1980) 83:66-73 Liburdy, RP Radiat. Res., (1979) 77:34-46 Liburdy, RP Radio Sci., (1977) 12:179-183
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