Recessive dystrophic epidermolysis bullosa is a monogenic skin blistering disorder caused by the mutations in the type VII collagen (COL7A1) gene. Combination of biological technologies, including induced pluripotent stem cells (iPSCs) and several gene-editing tools, allows us to realize gene and cell therapies for such inherited diseases. However, the methodology of gene and cell therapies must be consistently innovated for safety clinical use. In this study, we used CRISPR/Cas9 technology to correct the pathogenic mutation in RDEB-specific iPSCs, and piggyBac transposon system not to remain any residual gene fragments in the genome of iPSCs after correcting the mutation. We confirmed that mutation-corrected iPSCs (MC-iPSCs) had no genetic footprint and maintained “stemness”. When differentiating MC-iPSC into fibroblasts, the expression of type VII collagen was restored. Our study provided one of the safer approaches to establish gene and cell therapies for skin hereditary disorders for the future clinical use.

Footprint-free gene mutation correction in induced pluripotent stem cell (iPSC) derived from recessive dystrophic epidermolysis bullosa (RDEB) using CRISPR/Cas9 and piggyBac transposon system