Correction of junctional epidermolysis bullosa by transplantation of genetically modified epidermal stem cells.
The continuous renewal of human epidermis is sustained by stem cells contained in the epidermal basal layer and in hair follicles. Cultured keratinocyte stem cells, known as holoclones, generate sheets of epithelium used to restore severe skin, mucosal and corneal defects. Mutations in genes encoding the basement membrane component laminin 5 (LAM5) cause junctional epidermolysis bullosa (JEB), a devastating and often fatal skin adhesion disorder. Epidermal stem cells from an adult patient affected by LAM5-beta3-deficient JEB were transduced with a retroviral vector expressing LAMB3 cDNA (encoding LAM5-beta3), and used to prepare genetically corrected cultured epidermal grafts. Nine grafts were transplanted onto surgically prepared regions of the patient's legs. Engraftment was complete after 8 d. Synthesis and proper assembly of normal levels of functional LAM5 were observed, together with the development of a firmly adherent epidermis that remained stable for the duration of the follow-up (1 year) in the absence of blisters, infections, inflammation or immune response. Retroviral integration site analysis indicated that the regenerated epidermis is maintained by a defined repertoire of transduced stem cells. These data show that ex vivo gene therapy of JEB is feasible and leads to full functional correction of the disease.
Mavilio
Fulvio
F
Department of Biomedical Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41100 Modena, Italy. fulvio.mavilio@unimore.it
Pellegrini
Graziella
G
Ferrari
Stefano
S
Di Nunzio
Francesca
F
Di Iorio
Enzo
E
Recchia
Alessandra
A
Maruggi
Giulietta
G
Ferrari
Giuliana
G
Provasi
Elena
E
Bonini
Chiara
C
Capurro
Sergio
S
Conti
Andrea
A
Magnoni
Cristina
C
Giannetti
Alberto
A
De Luca
Michele
M
D016475:3T3 Cells; D000328:Adult; D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics; D002478:Cells, Cultured; D000078404:Epidermal Cells; D016109:Epidermolysis Bullosa, Junctional / Q000628:therapy*; D005240:Feasibility Studies; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D008297:Male; D051379:Mice; D012190:Retroviridae; D033581:Stem Cell Transplantation; D023822:Tissue Engineering / Q000379:methods; D000097794:Kalinin
D015815:Cell Adhesion Molecules; D000097794:Kalinin