Molecular Medicine and Gene Therapy, Lund University Hospital, Lund, Sweden

Correspondence to: S Karlsson, Molecular Medicine and Gene Therapy, Lund University Hospital, Sölvegatan 17, 223 62 Lund, Sweden; Fax: +46 46 222 0578

Lentiviral vectors are promising tools for the development of gene therapy since they can transduce both quiescent and dividing target cells. Lentiviral vectors may be particularly promising gene delivery tools for hematopoietic stem cells since these target cells tend to be quiescent and are therefore difficult target cells for vectors that require dividing targets. Human hematopoietic stem cells that can repopulate NOD/SCID mice have been efficiently transduced using HIV-1-based lentiviral vectors and similar vectors can also transduce murine hematopoietic stem cells. HIV-1 vectors that contain strong general promoters can generate high levels of transgene expression and very high expression levels can be generated in erythroid cells in vivo using -globin regulatory sequences to control the expression of the transgene. Current lentiviral vectors have a similar level of biosafety as oncoretroviral vectors and can therefore theoretically be used in clinical gene therapy protocols. Future challenges include the generation of lentiviral vectors that can express more than one transgene at high levels and the generation of safe permanent packaging cells for practical use in clinical gene therapy trials.

Leukemia (2002) 16, 563-569. DOI: 10.1038/sj/leu/2402447

lentiviral vectors; hematopoietic stem cells; gene therapy