In vivo correction of Recessive Dystrophic Epidermolysis Bullosa by gene editing mediated by adenoviral vectors. (Garcia-Diez 1)Ongoing
|Project lead||Prof Marta Garcia Diez|
|Organisation||CIEMAT - Centro de Investigaciones Energéticas Medioambientales y Tecnológicas, Madrid, SPAIN|
|Project budget||EUR 179,000.00 (EUR 100,000 DEBRA Spain, EUR 76,320 DEBRA Austria, EUR 2,680 DEBRA Sweden)|
|Start date / Duration||01. Jun 2023 / 36 months|
|Funder(s) / Co-Funder(s)||DEBRA Austria, DEBRA Spain, MSAP/EBEP Recommended, DEBRA Sweden|
|Research area||EB genetics, epigenetics & biology|
Publications related to the projectsPreclinical model for phenotypic correction of dystrophic epidermolysis bullosa by in vivo CRISPR-Cas9 delivery using adenoviral vectors
Short lay summary
Mutations in the gene encoding type VII collagen, the major component of the anchoring fibrils that bind the dermis and epidermis, cause recessive dystrophic epidermolysis bullosa, a devastating skin fragility disease characterized by recurrent skin blistering, scarring, and an increased risk of developing squamous cell carcinoma. Our aim is to develop a “gene cream” medicinal product based on a viral vector to deliver gene-correcting molecular tools. This product will be beneficial to individuals with mutations in exon 80 of the collagen VII-encoding gene, which accounts for a large proportion of Spanish patients with RDEB. Using mouse models of RDEB, we will work towards the formulation of this viral vector-based medication and develop conditions for effective in vivo gene-correcting treatment.
We intend to create a CRISPR-based drug using a viral vector design for COL7A1 gene correction delivered via biocompatible hydrogels. We previously demonstrated a gene editing approach for ex vivo gene correction using the CRISPR/Cas9 system to precisely excise exon 80 of COL7A1 carrying the c.6527 insC mutation, which is highly prevalent in the Spanish population of patients with RDEB. The topical administration of gene correction tools to implement the same pathogenic exon deletion strategy will allow the treatment of chronic open wounds. We developed helper-dependent adenoviral vectors (HDAd) carrying CRISPR system designs and found them to cause efficient exon 80 deletion after testing them in human keratinocytes and in the epithelial component of wounds in vivo. In this project, we will perform preclinical studies in immunocompetent mouse models to establish conditions for effective in vivo gene editing therapy delivered by adenoviral vectors. Specifically, we will test conditions and reagents for the delivery of HDAd vectors into wounds, including the formulation of vector carriers for skin and the comparison of immunosuppressive regimens that enable or enhance gene editing following single and repeated topical treatments using a mouse model in which expression of a fluorescent reporter protein is activated following CRISPR-mediated deletion. Next, we will test the feasibility of gene editing-mediated phenotypic correction of skin wounds in a mouse model of RDEB. Finally, for drug development based on a clinically relevant viral vector design for CRISPR-mediated COL7A1 modification, we will test the ability of vector/carrier compound formulations to drive long-term collagen VII expression in a humanized model of regenerated RDEB patient skin in immunodeficient mice.
Advances in gene editing technology coupled with advancements in viral vectors have enabled the design of corrective tools for direct administration to wounds, potentially providing long-term corrections. Previously, we demonstrated a CRISPR/Cas9-based gene-editing approach for ex vivo gene correction, specifically targeting exon 80 of COL7A1 with the c.6527 insC mutation, which is prevalent among Spanish patients with RDEB. Topical administration of gene correction tools using the same exon deletion strategy allows the treatment of chronic open wounds. Correcting the genetic variants responsible for dermal-epidermal adhesion loss in wounds of epidermolysis patients would be a significant advancement in improving their quality of life.