Characterization of Positively Charged Lipid Shell Microbubbles with Tunable Resistive Pulse Sensing (TRPS) Method: A Technical Note.

Microbubbles are polydisperse microparticles. Their size distribution cannot be accurately measured from the current methods used, such as optical microscopy, electrical sensing or light scattering. Indeed, these techniques present some limitations when applied to microbubbles, which prompted us to investigate the use of an alternative technique: tunable resistive pulse sensing (TRPS).

Magnetic and photoresponsive theranosomes: translating cell-released vesicles into smart nanovectors for cancer therapy.

Cell-released vesicles are natural carriers that circulate in body fluids and transport biological agents to distal cells. As nature uses vesicles in cell communication to promote tumor progression, we propose to harness their unique properties and exploit these biogenic carriers as Trojan horses to deliver therapeutic payloads to cancer cells. In a theranostic approach, cell-released vesicles were engineered by a top-down procedure from precursor cells, previously loaded with a photosensitizer and magnetic nanoparticles.

Investigating relationship between transfection and permeabilization by the electric field and/or the Pluronic® L64 in vitro and in vivo.

Background: Electrotransfer can be obtained by the successive delivery of a high voltage short duration pulse (HV) inducing membrane destabilization and then a low voltage long duration pulse (LV), allowing DNA electrophoresis (HVLV mode). Pluronic® L64 (L64) (Fluka, Sigma-Aldrich, L'Isle-d'Abeau Chesnes, Saint-Quentin Fallavier, France) has permeabilizing properties and amplifies the expression of DNA. We aimed to determine whether L64 could have an adjuvant effect on transfection by electrotransfer and whether the sequence L64 injection and then application of a LV pulse could induce transfection comparable to that observed with the HVLV mode.

In vivo bioluminescent imaging of a new model of infectious complications in head-injury rats.

Infectious complications are responsible for 10-25% of mortality in head-injured patients. In the present work we developed a model of infectious complications in head-injury rats using Escherichia coli (E. coli) with a stable copy of the lux operon, and monitored the infection in vivo by optical imaging.

Cationic and anionic lipoplexes inhibit gene transfection by electroporation in vivo.

Background: Nonviral gene therapy still suffers from low efficiency. Methods that would lead to higher gene expression level of longer duration would be a major advance in this field. Lipidic vectors and physical methods have been investigated separately, and both induced gene expression improvement.

Muscle transfection and permeabilization induced by electrotransfer or pluronic L64: Paired study by optical imaging and MRI.

Background: Muscle transfection by electrotranfer is an efficient currently used procedure. Recently, the block copolymer pluronic L64 has been reported to improve muscle transfection. Both procedures are known to permeabilize muscle fibres.

Optimisation of intradermal DNA electrotransfer for immunisation.

The development of DNA vaccines requires appropriate delivery technologies. Electrotransfer is one of the most efficient methods of non-viral gene transfer. In the present study, intradermal DNA electrotransfer was first optimised.

In vivo electrotransfer of interleukin-10 cDNA prevents endothelial upregulation of activated NF-kappaB and adhesion molecules following an atherogenic diet.

Objectives: Interleukin (IL)-10 has anti-atherogenic properties. However, the molecular mechanisms involved in IL-10 protection against atherosclerosis in vivo remain poorly understood. In this study, we examined the effect of IL-10 cDNA in vivo electrotransfer on diet-induced, endothelial activation.

Electrophoretic component of electric pulses determines the efficacy of in vivo DNA electrotransfer.

Efficient DNA electrotransfer can be achieved with combinations of short high-voltage (HV) and long low voltage (LV) pulses that cover two effects of the pulses, namely, target cell electropermeabilization and DNA electrophoresis within the tissue. Because HV and LV can be delivered with a lag up to 3000 sec between them, we considered that it was possible to analyze separately the respective importance of the two types of effects of the electric fields on DNA electrotransfer efficiency. The tibialis cranialis muscles of C57BL/6 mice were injected with plasmid DNA encoding luciferase or green fluorescent protein and then exposed to various combinations of HV and LV pulses.

Plasmid DNA electrotransfer for intracellular and secreted proteins expression: new methodological developments and applications.

In vivo electrotransfer is a physical method of gene delivery in various tissues and organs, relying on the injection of a plasmid DNA followed by electric pulse delivery. The importance of the association between cell permeabilization and DNA electrophoresis for electrotransfer efficiency has been highlighted. In vivo electrotransfer is of special interest since it is the most efficient non-viral strategy of gene delivery and also because of its low cost, easiness of realization and safety.

LPS-induced bronchial hyperreactivity: interference by mIL-10 differs according to site of delivery.

When administered to mice systemically or via the airways, LPS induces bronchoconstriction (BC) and/or bronchopulmonary hyperreactivity (BHR), associated with inflammation. Accordingly, a relationship between inflammation and allergic and nonallergic BHR can be hypothesized. We therefore studied the interference of the anti-inflammatory cytokine murine IL-10 (mIL-10) with LPS-induced lung inflammation, BC, and BHR.

Applications of plasmid electrotransfer.

The use of electric pulses to transfect cells has recently been extended to show the utility of this procedure in vivo. Electrotransfer has been performed in vivo on several tissue types including skin, blood vessels, liver, tumor, muscle, cornea, brain and spleen. The most widely targeted tissue has been skeletal muscle.

In vivo plasmid DNA electrotransfer.

In vivo electrotransfer is a physical technique for gene delivery in various mammalian tissues, which involves the injection of plasmid DNA into a target tissue and administration of an electric field. Its ease of performance, as well as recent understanding of its mechanism and applications to different mammalian tissues such as skeletal muscle, liver, brain and tumors, makes it a powerful technique. It could be used in gene therapy and as a laboratory tool to study gene functions.

Interleukin-10 expression after intramuscular DNA electrotransfer: kinetic studies.

Transfected muscle can be used as a secreting tissue for therapeutic proteins. Skeletal muscle transfection is increased by suitable electric pulse application (electrotransfer). We and others had shown that electrotransfer of interleukin-10 encoding plasmid is an effective strategy in animal models of chronic diseases such as myocarditis, atherosclerosis, or rheumatoid arthritis.

Mechanisms of in vivo DNA electrotransfer: respective contributions of cell electropermeabilization and DNA electrophoresis.

Efficient cell electrotransfection can be achieved using combinations of high-voltage (HV; 800 V/cm, 100 micros) and low-voltage (LV; 80 V/cm, 100 ms) pulses. We have developed equipment allowing the generation of various HV and LV combinations with precise control of the lag between the HV and LV pulses. We injected luciferase-encoding DNA in skeletal muscle, before or after pulse delivery, and measured luciferase expression after various pulse combinations.