Project electric pulses and electronic war: study of the interactions between waves and biology – PIERGEN

The objectives of the PIERGEN research project are to analyze the effects of short duration and high intensity electric field pulses on the living. Our strategy is to use waves of types radar and broadband (pulses), close to the objectives of the Defense and area of excellence of the CEA Gramat and to apply them on biological systems with increasing complexity (lipid vesicles, cell cultures on Petri dishes or cultivated in multicellular spheroids, small animal), systems of studies developed and used by the CNRS in Toulouse which has expertise in “classic” Electroporation. Previous work with monopolar and high amplitudes pulses highlight the Electroporation of cell membranes. Other effects, both at the membrane and intracellular levels, are likely to occur at lower fields. Thus, this work in synergy between the two partners has ambition to see the effect of these oscillatory bipolar “unconventional” pulses. Science and technology to lift locks are pushing the current boundaries of our knowledge in adapting our existing tools and in developing new ones. The potential direct effects on membranes and their consequences on cells and tissues will be studied by different imaging techniques with applicators who will be developed during the project. Thus the scientific program involves two aspects: 1) design of pulse generators (Illuminators antennal and laboratories) test TEM cells and applicators and 2) the study of their effects on biological models with increasing complexity.

The two types of waves (BUE: band Ultra narrow, radar and BL types: Broadband) have no visible effect on giant lipid vesicles (simplified model of cells) which the membrane suffers no loss of lipids, deformation, nor permeabilization.

The two types of waves (BUE: band Ultra narrow, radar and BL types: Broadband) have, to date, no effect on the two types of human cells (healthy or cancerous) used in this work. No change in size, shape or short term permeability is observed.

At the level of civil research, these data will be useful for the safe and efficient development in clinic of the «electroporation« method for the treatment of cancers by electrochemiotherapy and electrogenotherapy, a promising approach, but which is facing a lack of effectiveness because the limited passage of DNA in the nucleus. At the level of the Defense, in the context of electromagnetic weapons, these effects, reversible or not, will be useful to set thresholds of harm for the protection of persons and determine the margin between the ability to disrupt electronics and the risk for man.

The impedance matching allows an optimum coupling of the wave with the biological object under test. The idea was the subject of a patent application.

1 article and 1 communication to a congress.

Electromagnetic radiation, whether or not of natural origin, are ubiquitous in our environment. Their effects on live organisms, beneficial or harmful, are dependent on the dose and duration of the exposure. Understandind them is a crucial issue for civil and military research.
Endogenous electric fields play important roles in Biology (nerve excitation, ion transport, excretion of hormones, stimulation of cell division, tissue regeneration), processes linked to the transmembrane potential of cells. Pulse electric external can permeabilize cell. This process, called Electroporation or Electroporation, is a well-known method of vectorization. Its use in cancer research is promising. Developments in gene therapy face limited effectiveness. One strategy would be to disrupt the nuclear envelope, by using very short and very intense pulses, to permit the passage of DNA in the nucleus. Knowledge of the membrane and cellular phenomena induced by this type of pulse is only very partial.
Emerging electromagnetic applications developed for defense use waves of the same type: short pulses of high amplitude applied on limited periods. In order to neutralize the adversary electronics without violation of persons, it is necessary to know their biological effects to determine their thresholds of harm. This gap in knowledge of thresholds restricts the use of these future weapons. Previous work in "classical" with monopolar pulse Electroporation, non-representative of the systems used by defense, highlight permeabilization of cell membranes. Other effects are likely to occur at low levels of field, which must be the subject of new investigations.
The objective of the PIERGEN project is to determine the effects of two types of waves (BUE: Ultra narrow band of radar and BL types: large band). This project will be implemented in synergy between the IPBS-CNRS in Toulouse and the CEA in Gramat. These two labs are internationally recognized in their field of competence. Systems for non-classical electropermeabilsation, close to those of defense (bipolar and oscillatory pulses), will be used. Scientific and technological locks are pushing the current limits of our knowledge by adapting our existing tools and developing new ones. The strategy is to use biological systems to study complexity (lipid vesicles, cells in culture, multicellular spheroids, small animal) to study the direct or indirect effects that these pulses can have on cells and intracellular organelles.
The design and the realization of the applicators of waves is the first part of the project. These applicators, with centimeter and sub-millimeter dimensions, will offer the opportunity to study the effects of pulses on different biological systems at the laboratory scale. The second part of the project concerns the study of the molecular and cellular mechanisms induced by these pulses. The scope of investigations concerns the different components of the living, from the molecule to the full body. In order to visualize the effects, different microscopy tools will be used. The direct effects on membranes (deformation, loss of transverse asymmetry, permeabilization, fusion) and their consequences on cells and tissues (mortality, loss of cohesion, alteration of cytoskeleton, permeability of murine vessels from healthy tissues or tumor, tumor growth) will be studied.