Strategy for the Optimization of Read-Through Therapy for Junctional Epidermolysis Bullosa with COL17A1 Nonsense Mutation

Read-through therapy suppresses premature termination codons and induces read-through activity, consequently restoring missing proteins. Aminoglycosides are widely studied as read-through drugs in different human genetic disorders, including hereditary skin diseases. Our previous work revealed that aminoglycosides affect COL17A1 nonsense mutations and represent a therapeutic option to alleviate disease severity. However, the amount of restored type XVII collagen (C17) in C17-deficient junctional epidermolysis bullosa keratinocytes was <1% relative to that in normal keratinocytes and was achieved only after high-dose gentamicin treatment, which induced deep transcriptional changes. Therefore, in this study, we designed a strategy combining aminoglycosides with compounds known to reduce their side effects. We developed translational read-through-inducing drug cocktail, version 5 containing low dosage of aminoglycosides, CC-90009, NMDI-14, melatonin, and apocynin that was able to induce about 20% of missing C17 without cell toxicity or an effect on in vitro wound closure. Translational read-through-inducing drugs cocktail, version 5 significantly induced COL17A1 expression and reverted the proinflammatory phenotype of C17-deficient junctional epidermolysis bullosa keratinocytes. Evaluation of this drug cocktail regarding its stability, penetration, and efficacy as a topical treatment remains to be determined. Translational read-through-inducing drug cocktail, version 5 might represent an improved therapeutic strategy for junctional epidermolysis bullosa and for other genetic skin disorders.