Biology Reference
In-Depth Information
mobilized peripheral blood-derived stem cell transplantation. We studied the
reconstitution of myeloid and lymphoid compartments after the transplanta-
tion of autologous CD34 + bone marrow cells following gamma irradiation in
cynomolgus macaques.
Results
The bone marrow cells were first transduced ex vivo with a lentiviral vector
encoding eGFP, with a mean efficiency of 72% ± 4%. The vector used was
derived from the simian immunodeficiency lentivirus SIVmac251, VSV-g
pseudotyped and encoded eGFP under the control of the phosphoglycerate ki-
nase promoter. After myeloid differentiation, GFP was detected in colony-
forming cells (37% ± 10%). A previous study showed that transduction rates
did not differ significantly between colony-forming cells and immature cells
capable of initiating long-term cultures, indicating that progenitor cells and
highly immature hematopoietic cells were transduced with similar efficiency.
Blood cells producingeGFP were detected as early as three days after trans-
plantation, and eGFP-producing granulocyte and mononuclear cells persist-
ed for more than one year in the periphery.
Conclusion
The transplantation of CD34 + bone marrow cells had beneficial effects for the
ex vivo proliferation and differentiation of hematopoietic progenitors, favor-
ing reconstitution of the T- and B-lymphocyte, thrombocyte and red blood cell
compartments.
background
Gene therapy strategies hold promise for the treatment of hematopoietic disor-
ders. All hematopoietic lineages, including polymorphonuclear cells, monocytes,
lymphocytes and natural killer cells, and hematopoietic stem cells (HSC) - which
are capable of self-renewal and pluripotent differentiation - have been targeted
for transduction with therapeutic genes. Most diseases for which gene therapy
could be proposed require stable and long-lasting transgene expression for effi-
cacy. Retroviral vectors present the major advantage of integrating the transferred
DNA stably into the genome of target cells, which is then passed on to progeny.
However, they cannot infect and integrate into non dividing cells [1]. Most HSC
are quiescent [2], respond slowly to stimulation [3-7] and tend to differentiate
and lose their repopulating capacity upon stimulation [3,8-11]. Lentiviral vec-
tors can be used to transduce cells in growth arrest [12] in vivo and ex vivo[13],
thanks to interaction of the preintegration complex - composed of viral VPX
and integrase proteins - with the nuclear pore complex[14]. Vectors derived from
Search WWH ::




Custom Search