Lentiviral gene therapy rescues p47 chronic granulomatous disease and the ability to fight Salmonella infection in mice.

Chronic granulomatous disease (CGD) is an inherited primary immunodeficiency disorder characterised by recurrent and often life-threatening infections and hyperinflammation. It is caused by defects of the phagocytic NADPH oxidase, a multicomponent enzyme system responsible for effective pathogen killing. A phase I/II clinical trial of lentiviral gene therapy is underway for the most common form of CGD, X-linked, caused by mutations in the gp91 subunit of the NADPH oxidase. We propose to use a similar strategy to tackle p47-deficient CGD, caused by mutations in NCF1, which encodes the p47 cytosolic component of the enzymatic complex. We generated a pCCLCHIM-p47 lentiviral vector, containing the chimeric Cathepsin G/FES myeloid promoter and a codon-optimised version of the human NCF1 cDNA. Here we show that transduction with the pCCLCHIM-p47 vector efficiently restores p47 expression and biochemical NADPH oxidase function in p47-deficient human and murine cells. We also tested the ability of our gene therapy approach to control infection by challenging p47-null mice with Salmonella Typhimurium, a leading cause of sepsis in CGD patients, and found that mice reconstituted with lentivirus-transduced hematopoietic stem cells had a reduced bacterial load compared with untreated mice. Overall, our results potentially support the clinical development of a gene therapy approach using the pCCLCHIM-p47 vector.