Human COL7A1 -corrected induced pluripotent stem cells for the treatment of recessive dystrophic epidermolysis bullosa

Abstract

Patients with recessive dystrophic epidermolysis bullosa (RDEB) lack functional type VII collagen owing to mutations in the gene COL7A1 and suffer severe blistering and chronic wounds that ultimately lead to infection and development of lethal squamous cell carcinoma. The discovery of induced pluripotent stem cells (iPSCs) and the ability to edit the genome bring the possibility to provide definitive genetic therapy through corrected autologous tissues. We generated patient-derived COL7A1-corrected epithelial keratinocyte sheets for autologous grafting. We demonstrate the utility of sequential reprogramming and adenovirus-associated viral genome editing to generate corrected iPSC banks. iPSC-derived keratinocytes were produced with minimal heterogeneity, and these cells secreted wild-type type VII collagen, resulting in stratified epidermis in vitro in organotypic cultures and in vivo in mice. Sequencing of corrected cell lines before tissue formation revealed heterogeneity of cancer-predisposing mutations, allowing us to select COL7A1-corrected banks with minimal mutational burden for downstream epidermis production. Our results provide a clinical platform to use iPSCs in the treatment of debilitating genodermatoses, such as RDEB.

Stem Cells in Wound Healing: The Future of Regenerative Medicine? A Mini-Review

“…Taking advantage of these characteristics, Itoh et al [48] generated in vitro 3-D skin equivalents composed exclusively of human iPSC-derived keratinocytes and fibroblasts. Two recent studies have further proven this concept; Sebastiano et al [49] and Umegaki-Arao et al [50] successfully used human keratinocyte-derived iPSCs to reconstitute skin in vitro for the treatment of recessive dystrophic epidermolysis bullosa. Additionally, Yang et al [51] successfully differentiated iPSCs into folliculogenic human epithelial stem cells to regenerate all components of the hair follicle.…”

Mesenchymal stem cells: potential for therapy and treatment of chronic non-healing skin wounds

“…The authors successfully used human keratinocyte-derived iPSCs to reconstitute skin in vitro for the treatment of recessive dystrophic epidermolysis bullosa. 55 Indeed, active studies in both animal models and future clinical trials need be conducted to develop effective dosing, timing and delivery routes.…”

Management of chronic wounds in patients with dystrophic epidermolysis bullosa: challenges and solutions

“…Preclinical studies have shown remarkable results in terms of gene correction/excision using both in vivo and ex vivo approaches. [64][65][66][67][68][69][70] In addition, a previous study of ex vivo gene therapy in an individual with junctional EB demonstrated restoration of laminin 332 expression following retroviralmediated transfection of epidermal stem cells with the LAMB3 gene, with long-lasting phenotypic correction in the grafted skin. 71 A US trial is currently evaluating the safety and efficacy of a retroviral vector and genetically engineered epithelial graft cultured from the skin of patients with RDEB (ClinicalTrials.gov identifier: NCT01263379).…”