Correction of deficient CD34+ cells from peripheral blood after mobilization in a patient with congenital erythropoietic porphyria.
Congenital erythropoietic porphyria (CEP) is an inherited disease due to a deficiency in the uroporphyrinogen III synthase (UROS), the fourth enzyme of the heme pathway. It is characterized by accumulation of uroporphyrin I in the bone marrow, peripheral blood, and other organs. The onset of most cases occurs in infancy and the main symptoms are cutaneous photosensitivity and hemolysis. For severe transfusion-dependent cases, when allogeneic cell transplantation cannot be performed, autografting of genetically modified primitive/stem cells is the only alternative. In the present study, efficient mobilization of peripheral blood primitive CD34(+) cells was performed on a young adult CEP patient. Retroviral transduction of this cell population with the therapeutic human UROS (hUS) gene resulted in both enzymatic and metabolic correction of CD34(+)-derived cells, as demonstrated by the increase in UROS activity and by a 53% drop in porphyrin accumulation. A 10-24% gene transfer efficiency was achieved in the most primitive cells, as demonstrated by the expression of enhanced green fluorescent protein (EGFP) in long-term culture-initiating cells (LTC-IC). Furthermore, gene expression remained stable during in vitro erythroid differentiation. Therefore, these results are promising for the future treatment of CEP patients by gene therapy.
Mazurier
F
F
Laboratoire de Pathologie Moléculaire et Thérapie Génique, EA 484, Université Victor Segalen Bordeaux 2, France.
Géronimi
F
F
Lamrissi-Garcia
I
I
Morel
C
C
Richard
E
E
Ged
C
C
Fontanellas
A
A
Moreau-Gaudry
F
F
Morey
M
M
de Verneuil
H
H
D018952:Antigens, CD34 / Q000235:genetics / Q000378:metabolism*; D001853:Bone Marrow / Q000201:enzymology; D015870:Gene Expression; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D016086:Lentivirus / Q000235:genetics; D017092:Porphyria, Erythropoietic / Q000628:therapy*; D011166:Porphyrins / Q000378:metabolism; D012190:Retroviridae / Q000235:genetics*; D014161:Transduction, Genetic; D014407:Tumor Cells, Cultured; D014576:Uroporphyrinogen III Synthetase / Q000235:genetics*
D018952:Antigens, CD34; D011166:Porphyrins; D014576:Uroporphyrinogen III Synthetase