title: Protein delivery by Pseudomonas type III secretion system: Ex vivo complementation of p67(phox)-deficient chronic granulomatous disease.
abstract: Bacterial type III secretion system drives the translocation of virulence factors into the cystosol of host target cells. In phagocytes and in Epstein-Barr virus immortalized B lymphocytes, NADPH oxidase generates O(-2) through an electron transfer chain the activity of which depends on the assembly of three, p67(phox), p47(phox) and p40(phox) cytosolic activating factors with Rac 1/2 and a membrane redox component, cytochrome b(558). In p67(phox) deficient chronic granulomatous disease (CGD) patients, p67-phox is missing and NADPH oxidase activity is abolished. ExoS is a virulence factor of Pseudomonas aeruginosa which is secreted via the type III secretion system: it was fused with p67(phox). Pseudomonas aeruginosa synthesized and translocated the hybrid ExoS-p67(phox) fusion protein into the cytosol of B lymphocytes via the type III secretion system. Purified ExoS-p67(phox) hybrid protein was as efficient as normal recombinant p67(phox) in cell-free reconstitution of NADPH oxidase activity. Therefore, ExoS-p67(phox) was transferred via the type III secretion system of Pseudomonas aeruginosa into the cytosol of B lymphocytes from a p67(phox)-deficient CGD patient and functionally reconstituted NADPH oxidase activity. In the complementation process, ExoS acted as a molecular courier for protein delivery: the reconstitution of an active NADPH oxidase complex suggests type III secretion system to be a new approach for cellular therapy.
authors.affiliation: Groupe d'étude du processus inflammatoire (GREPI), MENRT EA 2938, Centre Hospitalier Universitaire de Grenoble, Grenoble, France. bpolack@chu-grenoble.fr
authors.forename: B
authors.initials: B
authors.lastname: Polack
authors.forename: S
authors.initials: S
authors.lastname: Vergnaud
authors.forename: M H
authors.initials: MH
authors.lastname: Paclet
authors.forename: D
authors.initials: D
authors.lastname: Lamotte
authors.forename: B
authors.initials: B
authors.lastname: Toussaint
authors.forename: F
authors.initials: F
authors.lastname: Morel
mesh_terms: D001402:B-Lymphocytes / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology / Q000473:pathology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D002461:Cell Line, Transformed; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D005816:Genetic Complementation Test; D006105:Granulomatous Disease, Chronic / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000502:physiology; D000071677:Histidine Kinase; D006801:Humans; D019255:NADPH Oxidases / Q000378:metabolism; D010750:Phosphoproteins / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014774:Virulence / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; C079789:neutrophil cytosol factor 67K; D019255:NADPH Oxidases; D011494:Protein Kinases; D000071677:Histidine Kinase