Epidermolysis bullosa (EB) is a painful rare genetic disorder resulting in easily blistered and broken skin, and without a cure. Recessive dystrophic EB (RDEB), the most severe form of EB, is caused by mutations in COL7A1 resulting in a lack of collagen VII between the epidermis and dermis. Reduction or complete loss of collagen VII in skin allows the dermis and epidermis to easily separate and form open wounds due to the loss of anchoring between to two layers. Current approaches to RDEB treatment are limited, and mainly targeting the symptoms rather than the underlying cause of the disease.
A promising treatment option for RDEB that targets the cause of the disease involves targeting COL7A1 with antisense oligonucleotides (ASOs). An ASO has been designed to restore production of collagen VII in RDEB patients with mutations in exon 73, which has the potential to restore skin integrity. The purpose of this study was to investigate the delivery of the ASO in skin cells and how it could be delivered to patients. Using high resolution confocal microscopy and expansion microscopy, the delivery of the ASO in dermal fibroblasts and keratinocytes has been further understood by demonstrating cell entry within 15 min and nuclear entry by 30 min. To develop a new method of ASO delivery to patients, a novel protocol of lipid transfection in ReCell was used. ReCell is an autologous treatment for wounds, scarring, and depigmentation that can be utilised for the treatment of skin genetic disorders. High efficiency of ASO transfection in ReCell has been achieved in surgical time points, allowing application of this method for clinical use. By understanding how ASOs can be delivered to patients with RDEB, the development of an ASO treatment for RDEB becomes one step closer, allowing patients’ better quality of life.