GENE-TRANSFER INTO HUMAN HEMATOPOIETIC STEM-CELLS

This review of gene transfer to the human haematopoietic system (1) de scribes the different vectors used to transduce genes into stem emphas izing retroviruses that already shown their efficiency innocuousness; (2) analyses which human cells should be targeted to ensure long-lasti ng engraftment; (3) indicates the different means of infecting these t argets ex vivo, underscoring the role of cytokines and stromal cells; (4) recollects the methods used to evaluate transduction efficiency; a nd (5) gathers the results of clinical trials recently performed using human stem cells. The major conclusions are that good practice can en sure safe gene delivery to human beings and that longlasting, multilin eal precursors can be transduced using retroviral vectors of marker ge nes or genes of therapeutic interest. However, transduction rates appe ar to remain relatively low, which should stimulate ongoing research o n both vector design and means of ex vivo gene transfer. (C) 1997 Else vier Science Ltd.