Immunomodulating effect of electromagnetic waves on production of tumor necrosis factor in mice with various rates of neoplasm growth

The effects of low-density centimeter waves (8.15-18 GHz, 1 microW/cm2, 1 h daily for 14 days; MW) on tumor necrosis factor production in macrophages of mice with different growth rate of a cancer solid model produced after hypodermic injection of Ehrlich carcinoma ascites cells into hind legs were studied. After irradiation, an increase in the concentration of tumor necrosis factor in immunocompetent cells of healthy and, specially, of tumor-bearing animals was observed; and the effect of stimulation was higher upon exposure of mice carrying rapidly growing tumors. We suggest that the significant immunomodulating effect of low-density microwaves can be utilized for tumor growth suppression.     

Effects of centimeter waves on the immune system of mice in endotoxic shock

The effects of centimeter waves (8.15-18 GHz, 1 microW/cm2, 1 h daily for 10 days; MW) on the production of the tumor necrosis factor alpha, interleukin-lalpha, interleukin-1beta, interleukin-2, and the expression of interleukin-6, interleukin-10, interferon-gamma, nitric oxide and HSP27, HSP72 and HSP90alpha in mice irradiated before or after LPS injection were studied. An acute endotoxic model was produced by a single LPS injection. The effects of microwaves on nitric oxide, interleukin-6, tumor necrosis factor-alpha, and interferon-gamma were dependent on the functional status of exposed animals. Thus, an exposure of healthy mice to microwaves for 10 days was followed by a decrease in nitric oxide and interferon-gamma production, and an increase in the production of the tumor necrosis factor-alpha and interleukin-6. On the contrary, an exposure to MW before intoxication resulted in an increase in the synthesis of nitric oxide and interferon-gamma as well as a decrease in the concentration of the tumor necrosis factor-alpha and interleukin-6 in blood of mice in endotoxic shock. When microwave exposure was used after LPS injection, it did not provide any protective effect, and preliminary irradiation enhanced the resistance of the organism to endotoxic shock.     

Effect oh millimeter waves on the immune system in mice with experimental tumors

The effect of low-level millimeter fractionated radiation on the production of tumor necrosis factor, intreleukin-2, interleukine-3, and nitric oxide and on the activity of natural killer cells and proliferation of T and B lymphocytes in mice was studied. Cell activity was measured in four groups of male Balb/c mice (control, exposed, tumor-bearing unexposed, and exposed tumor-bearing animals) within 30 days of tumoral growth and microwave exposure (42.2 GHz, 10 Hz amplitude modulation, 0.5 microW/cm2, 1.5 h daily). A significant increase in the production of tumor necrosis factor and nitric oxide and in the activity of natural killer cells was observed at the early stage of tumor development; this effect was considered as adaptive response. In healthy mice, millimeter radiation produced both stimulating and immunodepressive effects. The changes were nonmonotonous; as the exposure duration was increased, the stimulating effect became weaker and on day 30 it was not observed. Irradiation of tumor-bearing mice did not induce any significant changes in the activity of cells compared to unirradiated tumor-bearing animals. Moreover, exposure to millimeter waves impaired some characteristics of cell immunity in tumor-bearing mice. It was concluded that low-intensity millimeter waves do not increase the resistance against tumor as it was shown earlier in our experiments with centimeter waves.     

Effect of centimeter microwaves and the combined magnetic field on the tumor necrosis factor production in cells of mice with experimental tumors

The effect of fractionated exposure to low-intensity microwaves (8.15-18 GHz, 1 microW/cm2, 1.5 h daily for 7 days) and combined weak magnetic field (constant 65 1 microT; alternating--100 nT, 3-10 Hz) on the production of tumor necrosis factor in macrophages of mice with experimental solid tumors produced by transplantation of Ehrlich ascites carcinoma was studied. It was found that exposure of mice to both microwaves and magnetic field enhanced the adaptive response of the organism to the onset of tumor growth: the production of tumor necrosis factor in peritoneal macrophages of tumor-bearing mice was higher than in unexposed mice.     

Effect of electromagnetic waves in the centimeter range on the production of tumor necrosis factor and interleukin-3 in immunized mice

The effect of prolonged treatment with weak microwaves on the production of tumor necrosis factor and interleukin-3 in peritoneal macrophages and T cells of male NMRI mice twice immunized by affinity-purified carboanhydrase was studied. Against the back ground of a high titer of antibody production, a significant increase in the production of tumor necrosis factor in peritoneal macrophages and splenic T lymphocytes of immunized mice was revealed, and a much stronger effect was observed for irradiated immunized animals. A tendency to increased secretion of interleukin-3 for unirradiated and irradiated immunized animals was found; in the latter group of animals, the effect being more pronounced. The stimulation of production of the cytokins, especially tumor necrosis factor, by combination of antigenic stimulation and microwaves can be used in adjuvant therapy of various immune diseases.     

The Production of Tumor Necrosis Factor in Cells of Tumor-Bearing Mice After Total-Body Microwave Irradiation and Antioxidant Diet

The effects of repeated treatment with weak microwaves (MW) (8.15–18 GHz, 1 µW/cm², 1.5 h daily) and diet with antioxidants (AO) (β-carotene, α-tocopherol, and ubiquinone Q₉) on production of tumor necrosis factor (TNF) in macrophages and T lymphocytes of healthy and tumor-bearing mice (TBM) were studied. Tumor size and mortality of TBM were also followed. Microwave radiation and antioxidant diet stimulated production of TNF in cells from healthy mice. At early stages, tumor growth induced TNF production in mouse cells; however, this effect decreased as tumors grew. In TBM exposed to MW, TNF production was higher than in unirradiated TBM. Oppositely, AO diet induced TNF production in healthy mice but did not affect TNF secretion in TBM. Accordingly, prolonged treatment of TBM to MW, but not to AO diet, decreased tumor growth rate and increased overall animal longevity. These results suggest that diminished tumor growth rate due to extremely low-level MW exposure of mice carrying tumors, at least in part, was caused by enhancement in TNF production and accumulation of plasma TNF.     

Effect of centimeter microwaves on the antibody production in mice

The effect of low-intensity microwaves (8.15-18 GHz, 0.3 or 1 microW/cm2, 1.5 h daily for 30 days) on antibody production in healthy male NMRI mice after immunization with affinity-purified carboanhydrase isolated from bovine erythrocytes with and without Freund's adjuvant was studied. It was found that exposure to microwaves leads to an increase in the concentration of antibodies in blood plasma, the stimulating effect being more pronounced in the primary immune response. It is assumed that the effect of enhancement of the immune response by the action of centimeter microwaves can be used in the adjuvant therapy.     

A comparison of the effects of millimeter and centimeter waves on tumor necrosis factor production in mouse cells

The effects of millimeter (40 GHz) and centimeter (8.15-18.00 GHz) low-intensity waves on the production of tumor necrosis factor (TNE) in macrophages and lymphocytes from exposed mice as well as in exposed isolated cells were compared. It was found that the dynamics of TNF secretory activity of cells varies depending on the frequency and duration of exposure. The application of millimeter waves induced a nonmonotonous course of the dose-effect curve for TNF changes in macrophages and splenocytes. Alternately, a stimulation and a decrease in TNF production were observed following the application of millimeter waves. On the contrary, centimeter waves provoked an activation in cytokine production. It is proposed that, in contrast to millimeter waves, the single application of centimeter waves to animals (within 2 to 96 h) or isolated cells (within 0.5 to 2.5 h) induced a much more substantial stimulation of immunity.     

Effects of exposure of different skin areas to low-power laser light

The effect of He-Ne laser light of extremely low power (632.8 nm, 0.2 mW/cm²) on the immune status of mice bearing solid tumors was studied. The state of tumor-bearing animals was assessed taking into account the number of immunocompetent cells, concentration of cytokines (tumor necrosis factor and interleukin-2), production of nitric oxide, expression of heat shock proteins 70 and 90, and the activity of natural killer cells. The model of a solid tumor was formed by subcutaneous transplantation of Ehrlich ascite carcinoma cells to mice; the average lifespan of animals was approximately 55 days. Different areas of skin of tumor-bearing mice were irradiated with laser light either singly (1 min; dose, 0.012 J/cm²) or repeatedly (1 min every 3 days over 30 days; total dose, 0.1 J/cm²). It was established that long-term chronic exposure of mice bearing Ehrlich ascite carcinoma cells to low-power laser light in the thymus projection area and especially in the tumor projection area leads to a decrease in the natural antitumor potential, which is manifested in acceleration of tumor growth and a tendency to decrease in the lifespan of tumor-bearing mice. Conversely, stimulation of antitumor immunity was observed over several days after a single exposure to low-power laser radiation. The results suggest that it is expedient to continue studies of the immunomodulating effects of low-power laser light and demonstrate the necessity of monitoring the immune system in the course of laser therapy.     

Effects of exposure of different skin areas to low-power laser light

The effect of helium-neon laser light of extremely low power of 0.2 mW/cm2 and wavelength 632.8 nm on the immune status of mice bearing solid tumors was studied. The evaluation of the status of tumor-bearing animals was provided by taking into account the number of immune cells, cytokine concentration (tumor necrosis factor, interleukin 2, production of nitric oxide, expression of heat shock proteins (Hsp70 and Hsp90), and activity of natural killers. The model of a solid tumor was formed by subcutaneous injection of Ehrlich carcinoma cells, and average life span of tumor-bearing mice achieved about 55 days. Different areas of the skin of tumor-bearing mice were subjected either to a single (1 min, dose 0.012 J/cm3) or repeated exposure to laser light (1 min, 48-h intervals, 30 days). Two different areas were irradiated: the thymus projection area or a hind limb with solid tumors. The results showed that chronic exposure of tumor-bearing mice in the thymus projection area, and especially, hind limb, reduced the resistance, which manifested itself in the acceleration of tumor growth and a tendency of mouse life span to decrease. On the contrary, a single exposure stimulated the antitumor immunity for several days after the exposure. The results show the expediency of further investigation of the immunomodulative effects of low-power laser light and the necessity of monitoring the immune system during laser therapy.     

Stimulation of production of tumor necrosis factor by murine macrophages when exposed in vio and in vitro to weak electromagnetic waves in the centimeter range

Whole-body microwave sinusoidal irradiation of male NMRI mice, exposure of macrophages in vitro, and preliminary irradiation of culture medium with 8.15-18 GHz (1 Hz within) at a power density of 1 microW/cm2 caused a significant enhancement of tumor necrosis factor production in peritoneal macrophages. The role of microwaves as a factor interfering with the process of cell immunity is discussed.     

The role of protein kinase SAPK/JNK in cell responses to low-intensity nonionizing radiation

The effect of low-intensity laser light (He-Ne, 0.2 mW/cm², 632.8 nm, exposure time 1 min) or centimeter waves (8.15–18 GHz, 1 μW/cm², exposure time 1 h) on Phospho-SAPK/JNK production in mice lymphocytes was investigated. Normal isolated spleen lymphocytes or cells incubated previously with geldanamycin, an inhibitor of Hsp90, were used in the experiments. Significant stimulation of Phospho-SAPK/JNK production in lymphocytes after treatment with laser light or microwaves has been shown in both cell models. It was proposed that activation of the SAPK/JNK signal pathway plays one of the central roles in cellular stress response to low-power nonionizing radiation.     

Immunomodulating properties of bidistilled modified water

The effect of bidistilled modified water obtained by treating bidistilled water with static electric field in the cathode compartment of a diaphragm electrolyzer on the production of tumor necrosis factor and activity of natural killer cells of mice was studied. It was found that bidistilled modified water added to cultured murine macrophages increases the tumor necrosis factor production 2.5-3-fold. A similar degree of stimulation of tumor necrosis factor production was observed after peroral administration of bidistilled modified water for 10-25 days. The activity of natural killer cells under these conditions increased by 150%. The stimulation of these immunity system components responsible for the resistance of the organism to tumors led to a suppression of tumor growth in tumor-bearing mice receiving bidistilled modified water.     

The role of heat shock proteins HSP90 in the response of immune cells to centimeter microwaves

The effects of low-level electromagnetic waves (8.15-18 GHz, 1 microW/cm2, 1 h) on the production of heat shock proteins, several cytokines, and nitric oxide in isolated mouse macrophages and lymphocytes were examined both under normal conditions and after the treatment of the cells with geldanamycin (GA), a depressor of activity of the heat shock protein 90 (Hsp90). The irradiation of cells without GA induced the production of Hsp70, nitric oxide (NO), interleukin-1beta (IL-1beta), interleukin-10 (IL-10), and the tumor necrosis factor -alpha (TNF-alpha). No changes in the production of Hsp90 in irradiated cells were observed, but intracellular locations of Hsp25 and Hsp70 altered. The preliminary treatment of cells with GA did not remove the effects of microwaves: in these conditions, the synthesis of all cytokines tested, nitric oxide, as well as total and membrane amount of Hsp70, and the amount of Hsp25 in the cytoplasm and cytoskeleton increased. Moreover, the exposure of cells incubated with GA resulted in the reduction of Hsp90-alpha production.     

Inhibition of inflammatory angiogenesis by distant subcutaneous tumor in mice

We investigated angiogenesis, inflammatory cells accumulation and endogenous production of cytokines in sponge implants of tumor-bearing mice. Seven days after inoculation of Ehrlich tumor cells (2.5 x 10(6)), sponge discs were implanted subcutaneously in the dorsa of mice to induce the formation of fibrovascular tissue. The implants of tumor-bearing and non tumor-bearing animals were assessed for neovascularization and leukocyte accumulation, together with levels of relevant cytokines, vascular endothelial growth factor VEGF), tumor necrosis factor alpha (TNF-alpha), CXCL1-3/KC and CCL2/JE. In the implants of tumor-bearing animals angiogenesis (assessed by hemoglobin content and VEGF levels in the implants) and leukocyte accumulation (assessed by myeloperoxidase -MPO- and N- acetylglucosaminidase-NAG-enzyme activities) were all significantly less than those in the implants of non tumor-bearing animals. Although the chemokine CXCL1-3/KC was lower in the implants of tumor-bearing animals, the chemokine CCL2/JE was increased in this group. The production of TNF-alpha in the implants was not modified by the presence of the subcutaneous tumor. The combination of the methodologies used in this study has provided a novel approach to investigate the interaction between two distinct proliferating tissues that share common features (angiogenesis, cell recruitment, inflammation) and has shown that the predominant inhibitory effect of a tumor mass over repair process is associated with altered cytokine production.     

Effects of low-level combined static and weak low-frequency alternating magnetic fields on cytokine production and tumor development in mice

We investigated the effects of weak combined magnetic fields (MFs) produced by superimposing a constant MF (in the range 30 - 150 µT) and an alternating MF (100 or 200 nT) on cytokine production in healthy Balb/C male mice exposed 2 h daily for 14 days. The alternating magnetic field was a sum of several frequencies (ranging from 2.5 - 17.5 Hz). The frequencies of the alternating magnetic field were calculated formally based on the cyclotron resonance of ions of free amino acids (glutamic and aspartic acids, arginine, lysine, histidine, and tyrosine). The selection of different intensity and frequency combinations of constant and alternating magnetic fields was performed to find the optimal characteristics for cytokine production stimulation in immune cells. MF with a constant component of 60 μT and an alternating component of 100 nT, which was a sum of six frequencies (from 5 to 7 Hz), was found to stimulate the production of tumor necrosis factor-α, interferon-gamma, interleukin-2, and interleukin-3 in healthy mouse cells and induce cytokine accumulation in blood plasma. Then, we studied the effect of this MF on tumor-bearing mice with solid tumors induced by Ehrlich ascite carcinoma cells by observing tumor development processes, including tumor size, mouse survival rate, and average lifespan. Tumor-bearing mice exposed to a combined constant magnetic field of 60 μT and an alternating magnetic field of 100 nT containing six frequencies showed a strong suppression of tumor growth with an increase in survival rate and enhancement of average lifespan.     

Periodontopathic bacterial endotoxin-induced tumor necrosis factor alpha production was inhibited by exercise in mice

The effects of exercise on serum interleukin-6 and tumor necrosis factor alpha levels were investigated using mice. Five-week-old female BALB/c mice (Th2-biased) and C57BL/6 mice (Th1-biased) were divided into exercise and control groups. The exercise group was exercised in a rotating basket type treadmill for 1 h (5 r.p.m.). Blood was collected and the serum was separated immediately after exercise. The serum interleukin-6 and tumor necrosis factor alpha levels were measured using an Endogen ELISA kit. Exercise significantly increased the serum interleukin-6 level in the two strains of mice (P<0.05 and P<0.01). The tumor necrosis factor alpha level was decreased in the exercise group. Next, periodontopathic bacterial endotoxin (lipopolysaccharide) was administered after exercise, and the effects of exercise on the lipopolysaccharide-induced serum interleukin-6 and tumor necrosis factor alpha levels were investigated. Exercise inhibited lipopolysaccharide-induced tumor necrosis factor alpha production, suggesting it has a defensive action against endotoxin shock.     

Low Frequency Magnetic Fields Enhance Antitumor Immune Response against Mouse H22 Hepatocellular Carcinoma

Objective

Many studies have shown that magnetic fields (MF) inhibit tumor growth and influence the function of immune system. However, the effect of MF on mechanism of immunological function in tumor-bearing mice is still unclear.

Methods

In this study, tumor-bearing mice were prepared by subcutaneously inoculating Balb/c mice with hepatocarcinoma cell line H22. The mice were then exposed to a low frequency MF (0.4 T, 7.5 Hz) for 30 days. Survival rate, tumor growth and the innate and adaptive immune parameters were measured.

Results

MF treatment could prolong survival time (n = 28, p<0.05) and inhibit tumor growth (n = 9, p<0.01) in tumor-bearing mice. Moreover, this MF suppressed tumor-induced production of cytokines including interleukin-6 (IL-6), granulocyte colony- stimulating factor (G-CSF) and keratinocyte-derived chemokine (KC) (n = 9–10, p<0.05 or 0.01). Furthermore, MF exposure was associated with activation of macrophages and dendritic cells, enhanced profiles of CD4⁺ T and CD8⁺ T lymphocytes, the balance of Th17/Treg and reduced inhibitory function of Treg cells (n = 9–10, p<0.05 or 0.01) in the mice model.

Conclusion

The inhibitory effect of MF on tumor growth was related to the improvement of immune function in the tumor-bearing mice.     

Tumor necrosis factor stimulates interleukin-1 and prostaglandin E2 production in resting macrophages

We have investigated the effect of tumor necrosis factor on the release of interleukin-1 and PGE2 from murine resident peritoneal macrophages. Tumor necrosis factor causes an increase in the production of interleukin-1 and PGE2 with a maximum induction for both noted at 5.9 X 10(-8) M. While indomethacin decreased tumor necrosis factor induced PGE2 production, this cyclooxygenase inhibitor augmented tumor necrosis factor induced interleukin-1 production. Our data suggests that tumor necrosis factor may be an important immunopotentiating agent in addition to its previously described cytolytic and metabolic activities.