EFFICIENT RETROVIRAL TRANSDUCTION OF HUMAN BONE-MARROW PROGENITOR ANDLONG-TERM CULTURE-INITIATING CELLS - PARTIAL RECONSTITUTION OF CELLS FROM PATIENTS WITH X-LINKED CHRONIC GRANULOMATOUS-DISEASE BY GP91-PHOXEXPRESSION

The primary immunodeficiencies are attractive candidates for the devel opment of gene therapy approaches based on the transduction of hematop oietic cells. We have constructed a high-titer recombinant retrovirus for expression of gp91-phox, deficiencies of which cause the X-linked form of chronic granulomatous disease (X-CGD). We have used this vecto r to transduce human bone marrow, using either unfractionated mononucl ear cells or purified CD34(+) cells as targets and evaluated several i nfection protocols. Efficient gene transfer to progenitors and long-te rm culture-initiating cells (LTC-IC) was obtained for each target popu lation. Importantly for potential clinical application, this could be achieved without the use of exogenous cytokines or polybrene. Progenit ors representing each of the lineages detectable in vitro were transdu ced at equal efficiencies, The vector was shown partially to restore g p91-phox deficiency and nicotinamide adenine dinucleotide phosphate (N ADPH) oxidase activity in transduced cells derived from X-CGD patients . These data demonstrate that it is possible to transduce primitive hu man hematopoietic cells efficiently and reconstitute NADPH oxidase. (C ) 1996 by The American Society of Hematology.