Stable marking and transgene expression without progression to monoclonality in canine long-term hematopoietic repopulating cells transduced with lentiviral vectors.
Lentiviral gene transfer vectors have a number of potential advantages over gammaretroviral vectors including more efficient transduction of nondividing cells, a more favorable integration site profile, and the ability to accommodate large transgenes. Here, we present long-term follow-up data of animals that received lentivirus-transduced CD34-enriched cells. Six long-term surviving dogs were available for analysis. Transgene expression was analyzed from at least 12 months to more than 5 years after transplantation in peripheral blood cells and multiple cell lineages. All animals demonstrated long-term stable transgene expression in peripheral blood myeloid, lymphoid, and red blood cells as well as in platelets. Vector integration sites were analyzed by linear amplification-mediated polymerase chain reaction and showed a polyclonal repopulation pattern in all animals. There was no evidence of any development of monoclonality or leukemia in the animals. The stable long-term multilineage transgene expression, together with detection of the same integration site in myeloid and lymphoid cells, strongly suggests the transduction of long-term repopulating stem cells. Our data demonstrate safe and efficient transduction of multilineage long-term repopulating cells with lentiviral vectors and support the use of such vectors for gene therapy studies in patients.
Enssle
Joerg
J
Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
Trobridge
Grant D
GD
Keyser
Kirsten A
KA
Ironside
Christina
C
Beard
Brian C
BC
Kiem
Hans-Peter
HP
D000818:Animals; D018952:Antigens, CD34 / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D019070:Cell Lineage / Q000235:genetics / Q000502:physiology; D004285:Dogs; D005434:Flow Cytometry; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D016086:Lentivirus / Q000235:genetics / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014161:Transduction, Genetic; D019076:Transgenes / Q000235:genetics / Q000502:physiology*
D018952:Antigens, CD34; D001426:Bacterial Proteins; D008164:Luminescent Proteins; C054562:yellow fluorescent protein, Bacteria