title: Superior long-term repopulating capacity of G-CSF+plerixafor-mobilized blood: implications for stem cell gene therapy by studies in the Hbb(th-3) mouse model.
abstract: High numbers of genetically modified hematopoietic stem cells (HSCs) equipped with enhanced engrafting potential are required for successful stem cell gene therapy. By using thalassemia as a model, we investigated the functional properties of hematopoietic stem and progenitor cells (HSPCs) from Hbb(th3)/45.2(+) mice after mobilization with G-CSF, plerixafor, or G-CSF+plerixafor and the engraftment kinetics of primed cells after competitive primary and noncompetitive secondary transplantation. G-CSF+plerixafor yielded the highest numbers of HSPCs, while G-CSF+plerixafor-mobilized Hbb(th3)/45.2(+) cells, either unmanipulated or transduced with a reporter vector, achieved faster hematologic reconstitution and higher levels of donor chimerism over all other types of mobilized cells, after competitive transplantation to B6.BoyJ/45.1(+) recipients. The engraftment benefit observed in the G-CSF+plerixafor group was attributed to the more primitive stem cell phenotype of G-CSF+plerixafor-LSK cells, characterized by higher CD150(+)/CD48 expression. Moreover, secondary G-CSF+plerixafor recipients displayed stable or even higher chimerism levels as compared with primary engrafted mice, thus maintaining or further improving engraftment levels over G-CSF- or plerixafor-secondary recipients. Plerixafor-primed cells displayed the lowest competiveness over all other mobilized cells after primary or secondary transplantation, probably because of the higher frequency of more actively proliferating LK cells. Overall, the higher HSC yields, the faster hematological recovery, and the superiority in long-term engraftment indicate G-CSF+plerixafor-mobilized blood as an optimal graft source, not only for thalassemia gene therapy, but also for stem cell gene therapy applications in general.
authors.affiliation: 1 Hematology-BMT Unit, Gene and Cell Therapy Center , George Papanicolaou Hospital, Thessaloniki 57010, Greece .
authors.forename: Nikoleta
authors.initials: N
authors.lastname: Psatha
authors.forename: Eleni
authors.initials: E
authors.lastname: Sgouramali
authors.forename: Antonios
authors.initials: A
authors.lastname: Gkountis
authors.forename: Athanasios
authors.initials: A
authors.lastname: Siametis
authors.forename: Panayotis
authors.initials: P
authors.lastname: Baliakas
authors.forename: Varnavas
authors.initials: V
authors.lastname: Constantinou
authors.forename: Evangelia
authors.initials: E
authors.lastname: Athanasiou
authors.forename: Minas
authors.initials: M
authors.lastname: Arsenakis
authors.forename: Achilles
authors.initials: A
authors.lastname: Anagnostopoulos
authors.forename: Thalia
authors.initials: T
authors.lastname: Papayannopoulou
authors.forename: George
authors.initials: G
authors.lastname: Stamatoyannopoulos
authors.forename: Evangelia
authors.initials: E
authors.lastname: Yannaki
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000032:analysis; D001596:Benzylamines; D002453:Cell Cycle; D002470:Cell Survival; D003131:Combined Modality Therapy; D000080027:Cyclams; D004195:Disease Models, Animal; D017930:Genes, Reporter; D005822:Genetic Vectors; D006085:Graft Survival; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods*; D018380:Hematopoietic Stem Cell Transplantation; D006571:Heterocyclic Compounds / Q000494:pharmacology*; D016086:Lentivirus; D051379:Mice; D008817:Mice, Mutant Strains; D011828:Radiation Chimera; D011994:Recombinant Proteins / Q000494:pharmacology*; D013156:Splenectomy; D018183:Transplantation Chimera; D017086:beta-Thalassemia / Q000235:genetics / Q000601:surgery / Q000628:therapy*
chemical_list: D000943:Antigens, Differentiation; D001596:Benzylamines; D000080027:Cyclams; D006571:Heterocyclic Compounds; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; C088327:plerixafor