title: Prolonged multilineage clonal hematopoiesis in a rhesus recipient of CD34 positive cells marked with a RD114 pseudotyped oncoretroviral vector.
abstract: The ability to efficiently transfer a gene into repopulating hematopoietic stem cells would create many therapeutic opportunities. We have evaluated the ability of particles bearing an alternative envelope protein, that of the feline endogenous virus (RD114), to transduce stem cells in a nonhuman primate autologous transplantation model using rhesus macaques. We have previously shown this pseudotyped vector to be superior to the amphotropic vector at transducing cells in umbilical cord blood capable of establishing hematopoiesis in immunodeficient mice. Gene transfer efficiency as reflected by the number of genetically modified cells in hematopoietic tissues varied among the five monkeys studied from low levels (<1%) in three animals to much higher levels in two (20-60%). An animal that exhibited extremely high levels for several weeks was found by vector genome insertion site analysis to have reconstitution predominantly with a single clone of cells. This variability among animals is in keeping with computer simulations of reconstitution with limiting numbers of stem cells genetically modified at about 10% efficiency. Our studies provide insights into the biology of hematopoietic reconstitution and suggest approaches for increasing stem cell targeted gene transfer efficiency.
authors.affiliation: Division of Experimental Hematology, Department of Hematology/Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Patrick F
authors.initials: PF
authors.lastname: Kelly
authors.forename: Robert E
authors.initials: RE
authors.lastname: Donahue
authors.forename: Jody A
authors.initials: JA
authors.lastname: Vandergriff
authors.forename: Masaaki
authors.initials: M
authors.lastname: Takatoku
authors.forename: Aylin C
authors.initials: AC
authors.lastname: Bonifacino
authors.forename: Brian A
authors.initials: BA
authors.lastname: Agricola
authors.forename: Mark E
authors.initials: ME
authors.lastname: Metzger
authors.forename: Cynthia E
authors.initials: CE
authors.lastname: Dunbar
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Nienhuis
authors.forename: Elio F
authors.initials: EF
authors.lastname: Vanin
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000097:blood / Q000276:immunology*; D015139:Blotting, Southern; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism; D019070:Cell Lineage; D002999:Clone Cells / Q000166:cytology; D005434:Flow Cytometry; D015870:Gene Expression; D005822:Genetic Vectors / Q000235:genetics*; D049452:Green Fluorescent Proteins; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000276:immunology* / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics; D008253:Macaca mulatta; D023421:Models, Animal; D016133:Polymerase Chain Reaction; D012190:Retroviridae / Q000235:genetics; D013997:Time Factors; D014162:Transfection; D014182:Transplantation, Autologous; D014759:Viral Envelope Proteins / Q000235:genetics
chemical_list: D018952:Antigens, CD34; D008164:Luminescent Proteins; D014759:Viral Envelope Proteins; D049452:Green Fluorescent Proteins