In Vitro Exposure of Human Lymphocytes to 900 MHz CW and GSM Modulated Radiofrequency: Studies of Proliferation, Apoptosis and Mitochondrial Membrane Potential

Abstract Capri, M., Scarcella, E., Fumelli, C., Bianchi, E., Salvioli, S., Mesirca, P., Agostini, C., Antolini, A., Schiavoni, A., Castellani, G., Bersani, F. and Franceschi, C. In Vitro Exposure of Human Lymphocytes to 900 MHz CW and GSM Modulated Radiofrequency: Studies of Proliferation, Apoptosis and Mitochondrial Membrane Potential. Radiat. Res. 162, 211–218 (2004). The aim of this study was to investigate the nonthermal effects of radiofrequency (RF) fields on human immune cells exposed to a Global System for Mobile Communication (GSM) signal generated by a commercial cellular phone and by a sinusoidal non-modulated signal. To assess whether mobile phone RF-field exposure affects human immune cell functions, peripheral blood mononuclear cells (PBMCs) from healthy donors were exposed in vitro to a 900 MHz GSM or continuous-wave (CW) RF field 1 h/day for 3 days in a transverse electromagnetic mode (TEM) cell system (70–76 mW/kg average specific absorption rate, SAR). The cells were cultured for 48 or 72 h, and the following end points were studied: (1) mitogen-induced proliferation; (2) cell cycle progression; (3) spontaneous and 2-deoxy-d-ribose (dRib)-induced apoptosis; (4) mitochondrial membrane potential modifications during spontaneous and dRib-induced-apoptosis. Data obtained from cells exposed to a GSM-modulated RF field showed a slight decrease in cell proliferation when PBMCs were stimulated with the lowest mitogen concentration and a slight increase in the number of cells with altered distribution of phosphatidylserine across the membrane. On the other hand, cell cycle phases, mitochondrial membrane potential and susceptibility to apoptosis were found to be unaffected by the RF field. When cells were exposed to a CW RF field, no significant modifications were observed in comparison with sham-exposed cells for all the end points investigated.

[1]  C Haanen,et al.  A novel assay for apoptosis. Flow cytometric detection of phosphatidylserine expression on early apoptotic cells using fluorescein labelled Annexin V. , 1995, Journal of immunological methods.

[2]  M. Repacholi.  Low-level exposure to radiofrequency electromagnetic fields: health effects and research needs. , 1998, Bioelectromagnetics.

[3]  C Gabriel,et al.  The dielectric properties of biological tissues: I. Literature survey. , 1996, Physics in medicine and biology.

[4]  G.,et al.  Annexin V for Flow Cytometric Detection of Phosphatidylserine Expression on B Cells Undergoing Apoptosis , 2000 .

[5]  C. Franceschi,et al.  A new method for the cytofluorimetric analysis of mitochondrial membrane potential using the J-aggregate forming lipophilic cation 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1). , 1993, Biochemical and biophysical research communications.

[6]  P. Raskmark,et al.  Changes in cell proliferation due to environmental non-ionizing radiation: 2. Microwave radiation , 1998 .

[7]  C. Franceschi,et al.  Apoptosis‐like, reversible changes in plasma membrane asymmetry and permeability, and transient modifications in mitochondrial membrane potential induced by curcumin in rat thymocytes , 1998, FEBS letters.

[8]  D. Mckenzie,et al.  EFFECTS OF EXPOSURE TO ELECTROMAGNETIC RADIATION AT 835 MHz ON GROWTH, MORPHOLOGY AND SECRETORY CHARACTERISTICS OF A MAST CELL ANALOGUE, RBL‐2H3 , 1997, Cell biology international.

[9]  Guglielmo d'Ambrosio,et al.  Cytogenetic damage in human lymphocytes following GMSK phase modulated microwave exposure , 2002, Bioelectromagnetics.

[10]  P. Salomoni,et al.  D-ribose and deoxy-D-ribose induce apoptosis in human quiescent peripheral blood mononuclear cells. , 1994, Biochemical and biophysical research communications.

[11]  S. N. Hornsleth,et al.  Retarded time absorbing boundary conditions , 1994 .

[12]  Guanghui Cao,et al.  Effect of isothermal radiofrequency radiation on cytolytic T lymphocytes , 1996, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[13]  R. de Seze,et al.  Biological effects of amplitude-modulated radiofrequency radiation. , 1998, Scandinavian journal of work, environment & health.

[14]  Eduardo G Moros,et al.  Measurement of DNA Damage and Apoptosis in Molt-4 Cells after In Vitro Exposure to Radiofrequency Radiation , 2004, Radiation research.

[15]  A. Schiavoni,et al.  SAR generated by commercial cellular phones-phone modeling, head modeling, and measurements , 2000 .

[16]  Vijayalaxmi,et al.  Proliferation and cytogenetic studies in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation. , 1997, International journal of radiation biology.

[17]  Eduardo G. Moros,et al.  Cytogenetic Studies in Human Blood Lymphocytes Exposed In Vitro to Radiofrequency Radiation at a Cellular Telephone Frequency (835.62 MHz, FDMA) , 2001, Radiation research.

[18]  C. Franceschi,et al.  JC‐1, but not DiOC6(3) or rhodamine 123, is a reliable fluorescent probe to assess ΔΨ changes in intact cells: implications for studies on mitochondrial functionality during apoptosis , 1997, FEBS letters.

[19]  M. Repacholi,et al.  Health risks from the use of mobile phones. , 2001, Toxicology letters.

[20]  P Raskmark,et al.  The effects of radiofrequency fields on cell proliferation are non-thermal. , 1999, Bioelectrochemistry and bioenergetics.

[21]  John B. Shoven,et al.  I , Edinburgh Medical and Surgical Journal.

[22]  J. Gray,et al.  Flow cytometric measurement of total DNA content and incorporated bromodeoxyuridine. , 1983, Proceedings of the National Academy of Sciences of the United States of America.

[23]  Allen Taflove,et al.  Computational Electrodynamics the Finite-Difference Time-Domain Method , 1995 .

[24]  C. Franceschi,et al.  Mitochondrial modifications during rat thymocyte apoptosis: a study at the single cell level. , 1994, Experimental cell research.

[25]  A. Böyum.  Isolation of leucocytes from human blood. Further observations. Methylcellulose, dextran, and ficoll as erythrocyteaggregating agents. , 1968, Scandinavian journal of clinical and laboratory investigation. Supplementum.

[26]  Myron L. Crawford,et al.  Generation of Standard EM Fields Using TEM Transmission Cells , 1974 .

[27]  D. R. McKenzie,et al.  Electromagnetic radiation at 835 MHz changes the morphology and inhibits proliferation of a human astrocytoma cell line , 1997 .

[28]  C. Franceschi,et al.  Decreased susceptibility to oxidative stress-induced apoptosis of peripheral blood mononuclear cells from healthy elderly and centenarians , 2001, Mechanisms of Ageing and Development.

[29]  C. Franceschi,et al.  Extremely low frequency pulsed electromagnetic fields increase cell proliferation in lymphocytes from young and aged subjects. , 1989, Biochemical and biophysical research communications.