Real-time impedance feedback to enhance cutaneous gene electrotransfer in a murine skin model.

Electric field mediated gene delivery methods have the ability to efficiently transfect cells in vivo with an excellent safety profile. The method has historically used a fixed number of electric pulses with identical characteristics in induce delivery. Electrical treatment does not typically compensate for subject-to-subject variation and other differences.

Impedance spectroscopy as an indicator for successful in vivo electric field mediated gene delivery in a murine model.

In vivo gene electro transfer technology has been very successful both in animal models and in clinical trials over the past 20years. However, variable transfection efficiencies can produce inconsistent outcomes. This can be due to differences in tissue architecture and/or chemical composition which may effectively create unique biological environments from subject to subject that may respond differently to the identical electric pulses.

Direct Current Helium Plasma for Delivery of Plasmid DNA Encoding Erythropoietin to Murine Skin.

The use of electric fields to deliver DNA, called electroporation, has the potential to broadly impact vaccination and disease treatment. The evidence for this has emerged from a large number of recently completed and ongoing clinical trials. The methods for applying electric fields to tissues traditionally involve contact between metal electrodes and the tissue.

Fluorometric assay to compensate for non-viable cells during electroporation.

A fluorometric assay is described that allows adjustment for non-viable cells that result during electroporation. The technique, unlike others, relies on only one dye, requires a single instrument, and eliminates the need for a separate cell counting step. Murine melanoma (B16-F10) cells were electroporated using electric fields ranging from 400 to 2500 V/cm in the presence of SYTOX(®)-green.

Optimization of a plasma facilitated DNA delivery method.

Plasma-based methods have recently emerged as a technique for augmenting plasmid DNA delivery to skin. This delivery modality relies on the deposition of ionized gas molecules on to targeted cells or tissue to establish an electric field. It is hypothesized that this electric field results in the dielectric breakdown of cell membranes, making cells permeable to exogenous molecules.

Electrogenetherapy of B16.F10 murine melanoma tumors with an interleukin-28 expressing DNA plasmid.

Augmented delivery of cytokine-expressing DNA plasmids to subcutaneous tumors has been demonstrated to result in a level of enhanced anti-tumor activity. One delivery enhancement method which has been evaluated is in vivo electroporation (EP), a contact-dependent delivery technique where electric pulses are hypothesized to augment the transfer of DNA into cells and tissues through the induction of temporary cell membrane pores. Previous work by members of our group, as well as others, has demonstrated the anti-tumor effects of DNA plasmids expressing the cytokines IL-12 and IL-15.

Non-contact helium-based plasma for delivery of DNA vaccines. Enhancement of humoral and cellular immune responses.

Non-viral in vivo administration of plasmid DNA for vaccines and immunotherapeutics has been hampered by inefficient delivery. Methods to enhance delivery such as in vivo electroporation (EP) have demonstrated effectiveness in circumventing this difficulty. However, the contact-dependent nature of EP has resulting side effects in animals and humans.

Enhancement of antigen specific humoral immune responses after delivery of a DNA plasmid based vaccine through a contact-independent helium plasma.

Non-viral in vivo delivery of DNA, encoding for specific proteins, has traditionally relied on chemical or physical forces applied directly to tissues. Physical methods typically involve contact between an applicator/electrode and tissue and often results in transient subject discomfort. To overcome these limitations of contact-dependent delivery, a helium plasma source was utilized to deposit ionized gasses to treatment/vaccination sites without direct contact between the applicator and the tissues.

Characterization of plasma mediated molecular delivery to cells in vitro.

Ion-based strategies have recently emerged as a method to facilitate molecular delivery. These methods are attractive as they separate the applicator from the treatment site avoiding some issues encountered with other electrically driven methods. Current literature on plasma delivery has shown utility in vitro and in vivo for both drugs and genes.

Electrically mediated delivery of plasmid DNA to the skin, using a multielectrode array.

The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take full advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is a strong candidate to meet this delivery criterion.

Plasma facilitated delivery of DNA to skin.

Non-viral delivery of cell-impermeant drugs and DNA in vivo has traditionally relied upon either chemical or physical stress applied directly to target tissues. Physical methods typically use contact between an applicator, or electrode, and the target tissue and may involve patient discomfort. To overcome contact-dependent limitations of such delivery methodologies, an atmospheric helium plasma source was developed to deposit plasma products onto localized treatment sites.

Comparison of electrically mediated and liposome-complexed plasmid DNA delivery to the skin.

Background: Electroporation is an established technique for enhancing plasmid delivery to many tissues in vivo, including the skin. We have previously demonstrated efficient delivery of plasmid DNA to the skin utilizing a custom-built four-plate electrode. The experiments described here further evaluate cutaneous plasmid delivery using in vivo electroporation.

Feasibility study for focusing electric fields to mediate in vitro drug and gene delivery.

Electric field mediated drug and gene delivery is a novel method that uses pulsed electric fields to improve permeability of cell membranes and therefore desired agent uptake by tissues. In this paper, we describe the modeling and experimental proof of concept of a method to direct electric fields to subsequently focus drug or gene uptake at a desired site. The in vitro experimental results presented are consistent with simulation models and could be scaled into different in vivo applications that can concentrate the effects of electroporation and overcome several problems related to localized effects near the electrodes.

Electrochemotherapy for the treatment of human sarcoma in athymic rats.

Electrochemotherapy is the combined use of a chemotherapeutic agent and pulsed electric fields. Electrical treatment causes an increase in cell membrane permeability which allows the chemotherapeutic agent to more freely enter the tumor cells. Electrochemotherapy has been under development in clinical trials.

Effect of electrochemotherapy on muscle and skin.

The efficient delivery of drugs to tumors is an important tool for the treatment of a variety of cancers. Electric pulses have been shown to facilitate the uptake of molecules through the cell membrane. This procedure has been successful in increasing the effectiveness of anti-tumor agents (electrochemotherapy; ECT).

Electric field enhanced plasmid delivery to liver hepatocellular carcinomas.

Electric field enhanced molecular delivery for cancer research and treatment is a new technology that has demonstrated its effectiveness in clinical trials using bleomycin or cisplatin (Heller, R., Gilbert, R., Jaroszeski, M.