Peripheral stem cells in bone marrow transplantation. Peripheral blood stem cell and gene therapy

Mobilized peripheral blood stem cells characterized by sustained re-populating ability could be optimal target cells for ex-vivo gene transfer. In spite of very attractive preliminary results obtained in the murine studies, therapeutically efficient gene transfer and expression in human targeted cells must be proven. In recent years, effort has been spent on the identification of factors limiting gene transfer efficiency of haematopoietic stem cells. Increasing knowledge concerning haematopoiesis and gene transfer has helped in identifying a number of limiting factors. These factors as well as the strategies that showed increased retroviral infection of haematopoietic stem cells will be discussed. Finally, the results of the clinical trials will be reported.