Prevention of distal flap necrosis in a rat random skin flap model by gene electro transfer delivering VEGF(165) plasmid.

Background Therapeutic delivery of angiogenic growth factors is a promising approach for treating ischemia observed in skin flaps and chronic wounds.Several studies have demonstrated that vascular endothelial growth factor(VEGF) helps mitigate skin flap necrosis by facilitating angiogenesis. The present study aimed to demonstrate an electrically-mediated nonviral gene delivery approach using a non-invasive multi-electrode array (MEA) for effective treatment of ischemic skin flaps.Methods We used a standard random dorsal skin flap model in rats. The study aimed to determine the optimal treatment sites on the skin flap, optimal plasmid dose and timing of the treatment for preventing distal flap necrosis.Results We determined that two treatment sites on the ischemic flap with a plasmid dose of 50-100 µg per treatment site proved adequate to prevent 95% flap necrosis, and that this was significantly better than the no treatment or injection only group. A 2-day window was critical to deliver the VEGF to achieve flap survival and prevent necrosis. Histological examination demonstrated minimal electro transfer associated tissue damage.Conclusions Our results demonstrate that MEA can be used as a non-invasive physical gene delivery method for plasmid VEGF, resulting in a significant reduction of necrosis in ischemic wounds. We propose that this method could be translated into a potential therapeutic approach to deliver growth factors to prevent ischemia in cases of chronic wounds, burns and skin flap necrosis.

Topical gene electrotransfer to the epidermis of hairless guinea pig by non-invasive multielectrode array.

Topical gene delivery to the epidermis has the potential to be an effective therapy for skin disorders, cutaneous cancers, vaccinations and systemic metabolic diseases. Previously, we reported on a non-invasive multielectrode array (MEA) that efficiently delivered plasmid DNA and enhanced expression to the skin of several animal models by in vivo gene electrotransfer. Here, we characterized plasmid DNA delivery with the MEA in a hairless guinea pig model, which has a similar histology and structure to human skin. Significant elevation of gene expression up to 4 logs was achieved with intradermal DNA administration followed by topical non-invasive skin gene electrotransfer. This delivery produced gene expression in the skin of hairless guinea pig up to 12 to 15 days. Gene expression was observed exclusively in the epidermis. Skin gene electrotransfer with the MEA resulted in only minimal and mild skin changes. A low level of human Factor IX was detected in the plasma of hairless guinea pig after gene electrotransfer with the MEA, although a significant increase of Factor IX was obtained in the skin of animals. These results suggest gene electrotransfer with the MEA can be a safe, efficient, non-invasive skin delivery method for skin disorders, vaccinations and potential systemic diseases where low levels of gene products are sufficient.

Enhanced killing effect of nanosecond pulse electric fields on PANC1 and Jurkat cell lines in the presence of Tween 80.

We investigated the effects of nanosecond pulse electric fields (nsPEFs) on Jurkat and PANC1 cells, which are human carcinoma cell lines, in the presence of Tween 80 (T80) at a concentration of 0.18% and demonstarted an enhanced killing effect. We used two biological assays to determine cell viability after exposing cells to nsPEFs in the presence of T80 and observed a significant increase in the killing effect of nsPEFs. We did not see a toxic effect of T80 when cells were exposed to surfactant alone. However, we saw a synergistic effect when cells exposed to T80 were combined with the nsPEFs. Increasing the time of exposure for up to 8 h in T80 led to a significant decrease in cell viability when nsPEFs were applied to cells compared to control cells. We also observed cell type-specific swelling in the presence of T80. We suggest that T80 acts as an adjuvant in facilitating the effects of nsPEFs on the cell membrane; however, the limitations of the viability assays were addressed. We conclude that T80 may increase the fragility of the cell membrane, which makes it more susceptible to nsPEF-mediated killing.

In-depth proteomic analyses of direct expressed prostatic secretions.

It is expected that clinically obtainable fluids that are proximal to organs contain a repertoire of secreted proteins and shed cells reflective of the physiological state of that tissue and thus represent potential sources for biomarker discovery, investigation of tissue-specific biology, and assay development. The prostate gland secretes many proteins into a prostatic fluid that combines with seminal vesicle fluids to promote sperm activation and function. Proximal fluids of the prostate that can be collected clinically are seminal plasma and expressed prostatic secretion (EPS) fluids. In the current study, MudPIT-based proteomics was applied to EPS obtained from nine men with prostate cancer and resulted in the confident identification of 916 unique proteins. Systematic bioinformatics analyses using publicly available microarray data of 21 human tissues (Human Gene Atlas), the Human Protein Atlas database, and other published proteomics data of shed/secreted proteins were performed to systematically analyze this comprehensive proteome. Therefore, we believe this data will be a valuable resource for the research community to study prostate biology and potentially assist in the identification of novel prostate cancer biomarkers. To further streamline this process, the entire data set was deposited to the Tranche repository for use by other researchers.