Enhanced host defense after gene transfer in the murine p47phox-deficient model of chronic granulomatous disease.
The p47phox-/- mouse exhibits a phenotype similar to that of human chronic granulomatous disease (CGD) and, thus, is an excellent model for the study of gene transfer technology. Using the Moloney murine leukemia virus-based retroviral vector MFG-S encoding the human form of p47phox, we performed ex vivo gene transfer into Sca-1+ p47phox-/- marrow progenitor cells without conditioning of donors with 5-fluorouracil. Transduced progenitors were transplanted into moderately irradiated (500 cGy), G-CSF preconditioned sibling p47phox-/- mice. Using the fluorescent probe dihydrorhodamine 123 (DHR), in vivo biochemical correction of the superoxide-generating NADPH oxidase system was detected by flow cytometry in 12.3% +/- 0.9% of phorbol myristate acetate-stimulated peripheral blood neutrophils at 4 weeks and 2.6% +/- 1.0% at 14 weeks after transplantation. Following gene therapy, mice were challenged with the CGD pathogen Burkholderia (formerly Pseudomonas) cepacia and bacteremia levels were assessed at 24 hours and 7 days after inoculation. At both time points, bacteremia levels in gene corrected p47phox-/- mice were significantly lower than untreated p47phox-/- mice (0.89 +/- 0.30 colonies v 237.7 +/- 83.6 colonies at 24 hours, P < .02; 4.0 +/- 2.0 colonies v 110.2 +/- 26.5 colonies at 7 days, P < .0014). More importantly, Kaplan-Meier survival analysis showed a significant survival advantage of gene corrected versus untreated p47phox-/- mice (P < .001). Thus, stem-cell-directed ex vivo gene therapy is capable of restoring phagocyte oxidant-dependent host-defense function in this mouse model of a human immune-system disorder.
Mardiney
M
M
Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1886, USA.
Jackson
S H
SH
Spratt
S K
SK
Li
F
F
Holland
S M
SM
Malech
H L
HL
D000818:Animals; D016470:Bacteremia / Q000209:etiology / Q000517:prevention & control; D016026:Bone Marrow Transplantation; D019121:Burkholderia Infections / Q000209:etiology / Q000517:prevention & control; D018076:DNA, Complementary / Q000235:genetics; D004198:Disease Susceptibility; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics; D006105:Granulomatous Disease, Chronic / Q000235:genetics / Q000628:therapy*; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008979:Moloney murine leukemia virus / Q000235:genetics; D019255:NADPH Oxidases; D010750:Phosphoproteins / Q000172:deficiency / Q000235:genetics*; D011828:Radiation Chimera
D018076:DNA, Complementary; D010750:Phosphoproteins; D019255:NADPH Oxidases; C060505:neutrophil cytosolic factor 1