The effect of successful low-dose immunotherapy ascertained by provocation neutralization on lymphocytic calcium ion influx following electric field exposure.

Background Low-dose immunotherapy affects baseline levels of intracellular calcium. However, the effect of background electric fields is yet to be ascertained. The aim of this study was to test the following hypotheses: desensitization by low-dose immunotherapy is associated with reduced calcium ion influx during electric field exposure; the effect of low-dose immunotherapy on intracellular calcium ion concentration does not depend on electric field exposure; and the intracellular calcium ion concentration is amplified by electric field exposure. Methods The experimental design was balanced and orthogonal. Intracellular lymphocytic calcium ion concentrations were assayed in 47 patients, following incubation with picogram amounts of 12 test allergens, using a cell-permeable calcium-sensing ratiometric fluorescent dye and fluorescence spectroscopy, both at baseline and following successful provocation neutralization treatment with low-dose immunotherapy. Duplicates were also exposed to an electric field which replicated the frequency spectrum measured in a non-Faraday shielded room. Results A significant or trend-level main effect was found for low-dose immunotherapy for: benzoate; formaldehyde; metabisulfite; natural gas; nitrosamines; organophosphates; salicylate; azo-dyes and precursors; nickel; and petrol (gasoline) exhaust. Significant or trend-level main effects for electric field exposure were observed for: formaldehyde; mercury (inorganic); natural gas; nickel; nitrosamines; petrol exhaust; salicylate; benzoate; and metabisulfite. There was no evidence of a statistical interaction between these two factors. Electric field exposure was associated with a higher intracellular calcium ion concentration. Conclusion There was support for all three hypotheses. The results suggest that patients may experience increased sensitivity to allergens as a result of exposure to everyday electric fields.