Moderate Heat-Assisted Gene Electrotransfer as a Potential Delivery Approach for Protein Replacement Therapy through the Skin

Abstract

Gene-based approaches for protein replacement therapies have the potential to reduce the number of administrations. Our previous work demonstrated that expression could be enhanced and/or the applied voltage reduced by preheating the tissue prior to pulse administration. In the current study, we utilized our 16-pin multi-electrode array (MEA) and incorporated nine optical fibers, connected to an infrared laser, between each set of four electrodes to heat the tissue to 43 °C. For proof of principle, a guinea pig model was used to test delivery of reporter genes. We observed that when the skin was preheated, it was possible to achieve the same expression levels as gene electrotransfer without preheating, but with a 23% reduction of applied voltage or a 50% reduction of pulse number. With respect to expression distribution, preheating allowed for delivery to the deep dermis and muscle. This suggested that this cutaneous delivery approach has the potential to achieve expression in the systemic circulation, thus this protocol was repeated using a plasmid encoding Human Factor IX. Elevated Factor IX serum protein levels were detected by ELISA up to 100 days post gene delivery. Further work will involve optimizing protein levels and scalability in an effort to reduce application frequency.

Invasive and non-invasive electrodes for successful drug and gene delivery in electroporation-based treatments

“…Interestingly, it was found that moderate tissue preheating before pulse exposure could potentially enhance gene expression while reducing the PEF strength. The minimally invasive electrode array (MEA) with optical fibers for heat production was introduced by the Heller group ( Edelblute et al, 2021 ). The purposed technique was applied on the skin; however, gene expression was also present in deeper layers, including the muscle ( Bulysheva et al, 2019 ).…”

A Microfluidic System of Gene Transfer by Ultrasound

“…However, the application of viral vectors is greatly limited due to limited DNA loading, difficult vector assembly, low efficiency of in vivo introduction, and high costs. Although non-viral vectors such as liposomes, polymer materials, and nano gene transporters have no defects, such as viral toxicity or immunogenicity, their transmission efficiency is very low [ 6 , 7 ]. The active methods for naked DNA transfer include: microinjection, particle bombardment/particle gun, electroporation, and optical methods [ 8 , 9 , 10 ].…”