Metabolic correction of congenital erythropoietic porphyria with iPSCs free of reprogramming factors.
Congenital erythropoietic porphyria (CEP) is due to a deficiency in the enzymatic activity of uroporphyrinogen III synthase (UROS); such a deficiency leads to porphyrin accumulation and results in skin lesions and hemolytic anemia. CEP is a candidate for retrolentivirus-mediated gene therapy, but recent reports of insertional leukemogenesis underscore the need for safer methods. The discovery of induced pluripotent stem cells (iPSCs) has opened up new horizons in gene therapy because it might overcome the difficulty of obtaining sufficient amounts of autologous hematopoietic stem cells for transplantation and the risk of genotoxicity. In this study, we isolated keratinocytes from a CEP-affected individual and generated iPSCs with two excisable lentiviral vectors. Gene correction of CEP-derived iPSCs was obtained by lentiviral transduction of a therapeutic vector containing UROS cDNA under the control of an erythroid-specific promoter shielded by insulators. One iPSC clone, free of reprogramming genes, was obtained with a single proviral integration of the therapeutic vector in a genomic safe region. Metabolic correction of erythroblasts derived from iPSC clones was demonstrated by the disappearance of fluorocytes. This study reports the feasibility of porphyria gene therapy with the use of iPSCs.
Institut National de la Santé et de la Recherche Médicale U, Biothérapies des Maladies Génétiques et Cancers, Laboratoire d'Excellence du Globule Rouge, Bordeaux, France.
Aurélie
A
Bedel
Miguel
M
Taillepierre
Véronique
V
Guyonnet-Duperat
Eric
E
Lippert
Pierre
P
Dubus
Sandrine
S
Dabernat
Thibaud
T
Mautuit
Bruno
B
Cardinaud
Catherine
C
Pain
Benoît
B
Rousseau
Magalie
M
Lalanne
Cécile
C
Ged
Yann
Y
Duchartre
Emmanuel
E
Richard
Hubert
H
de Verneuil
François
F
Moreau-Gaudry
D002454:Cell Differentiation; D005240:Feasibility Studies; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000637:transplantation*; D015603:Keratinocytes / Q000166:cytology; D016086:Lentivirus / Q000235:genetics; D017092:Porphyria, Erythropoietic / Q000235:genetics / Q000628:therapy*; D014161:Transduction, Genetic; D014576:Uroporphyrinogen III Synthetase / Q000235:genetics*
D014576:Uroporphyrinogen III Synthetase