title: Correction of murine sickle cell disease using gamma-globin lentiviral vectors to mediate high-level expression of fetal hemoglobin.
abstract: Increased levels of red cell fetal hemogloblin, whether due to hereditary persistence of expression or from induction with hydroxyurea therapy, effectively ameliorate sickle cell disease (SCD). Therefore, we developed erythroid-specific, gamma-globin lentiviral vectors for hematopoietic stem cell (HSC)-targeted gene therapy with the goal of permanently increasing fetal hemoglobin (HbF) production in sickle red cells. We evaluated two different gamma-globin lentiviral vectors for therapeutic efficacy in the BERK sickle cell mouse model. The first vector, V5, contained the gamma-globin gene driven by 3.1 kb of beta-globin regulatory sequences and a 130-bp beta-globin promoter. The second vector, V5m3, was identical except that the gamma-globin 3'-untranslated region (3'-UTR) was replaced with the beta-globin 3'-UTR. Adult erythroid cells have beta-globin mRNA 3'-UTR-binding proteins that enhance beta-globin mRNA stability and we postulated this design might enhance gamma-globin expression. Stem cell gene transfer was efficient and nearly all red cells in transplanted mice expressed human gamma-globin. Both vectors demonstrated efficacy in disease correction, with the V5m3 vector producing a higher level of gamma-globin mRNA which was associated with high-level correction of anemia and secondary organ pathology. These data support the rationale for a gene therapy approach to SCD by permanently enhancing HbF using a gamma-globin lentiviral vector.
authors.affiliation: Division of Experimental Hematology, Department of Hematology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
authors.forename: Tamara I
authors.initials: TI
authors.lastname: Pestina
authors.forename: Phillip W
authors.initials: PW
authors.lastname: Hargrove
authors.forename: Dennis
authors.initials: D
authors.lastname: Jay
authors.forename: John T
authors.initials: JT
authors.lastname: Gray
authors.forename: Kelli M
authors.initials: KM
authors.lastname: Boyd
authors.forename: Derek A
authors.initials: DA
authors.lastname: Persons
mesh_terms: D000755:Anemia, Sickle Cell / Q000628:therapy*; D000818:Animals; D015139:Blotting, Southern; D002478:Cells, Cultured; D004586:Electrophoresis; D005319:Fetal Hemoglobin / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005434:Flow Cytometry; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics*; D018380:Hematopoietic Stem Cell Transplantation; D016086:Lentivirus / Q000235:genetics*; D051379:Mice; D008957:Models, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000378:metabolism / Q000473:pathology; D055545:gamma-Globins / Q000235:genetics*
chemical_list: D055545:gamma-Globins; D005319:Fetal Hemoglobin