Successful therapeutic transplantation of revertant skin in epidermolysis bullosa.

ABSTRACT

BACKGROUND: Epidermolysis bullosa (EB) is a group of genetic blistering diseases. Despite many efforts, treatment for EB remains symptomatic. Revertant mosaicism, coexistence of cells carrying disease-causing mutations with cells in which the inherited mutation is genetically corrected by a spontaneous genetic event (revertant cells) in 1 individual, can be found in EB. The naturally corrected revertant keratinocytes provide an opportunity for autologous cell therapy. OBJECTIVE: We sought to locally treat EB by transplantation of revertant skin. METHODS: Persistent ulcers in a patient with non-Herlitz junctional EB caused by mutations in the LAMB3 gene were treated by transplantation of split-thickness biopsy specimens from one of his revertant patches. RESULTS: All transplanted biopsy specimens were accepted and complete re-epithelialization occurred within 14 days. During 18 months of follow-up, the patient never experienced blisters or wounds in the grafted area, nor in the healed donor site. Immunofluorescence and DNA sequencing showed that acceptor sites healed with transplanted revertant keratinocytes. LIMITATIONS: Punch grafting allows only limited expansion of revertant skin. CONCLUSIONS: We demonstrate that phenotypical and genotypical correction of skin in patients with revertant mosaicism by expansion of revertant skin might be a promising therapeutic option for cutaneous manifestations of EB.