title: Delivery of biologically active anti-inflammatory cytokines IL-10 and IL-1ra in vivo by the Shigella type III secretion apparatus.
abstract: Pathogenicity of many Gram-negative bacteria relies on a type III secretion (T3S) apparatus, which is used for delivery of bacterial effectors into the host cell cytoplasm allowing the bacteria to manipulate host cell cytoskeleton network as well as to interfere with intracellular signaling pathways. In this study, we investigated the potential of the Shigella flexneri T3SA as an in vivo delivery system for biologically active molecules such as cytokines. The anti-inflammatory cytokines IL-10 and IL-1 receptor antagonist (IL-1ra) were genetically fused to the first 30 or 60 residues of the Shigella T3S effector IpaH9.8 or to the first 50 residues of the Yersinia enterocolitica effector YopE and the recombinant fusion proteins were expressed in S. flexneri. YopE(50)-IL-10, IpaH(60)-IL-10, and IpaH(60)-IL-1ra were efficiently secreted via the T3S apparatus of Shigella. Moreover, these recombinant proteins did not impair the invasive ability of the bacteria in vitro. In a murine model, Shigella strains expressing YopE(50)-IL-10, IpaH(60)-IL-10, and IpaH(60)-IL-1ra induced a lower mortality in mice that was associated with reduced inflammation and a restricted localization of bacteria within the lung tissues as compared with wild-type Shigella. Moreover, the level of TNF-alpha and IL-1beta mRNA were reduced in the lungs following infection by IL-10- and IL-1ra-secreting Shigella, respectively. These findings demonstrate that the Shigella T3S apparatus can deliver biologically active cytokines in vivo, thus opening new avenues for the use of attenuated bacteria to deliver proteins for immunomodulation or gene therapy purposes.
authors.affiliation: Laboratoire de Bactériologie Moléculaire, Faculté de Médecine, Université Libre de Bruxelles, Brussels, Belgium. mchamekh@ulb.ac.be
authors.forename: Mustapha
authors.initials: M
authors.lastname: Chamekh
authors.forename: Armelle
authors.initials: A
authors.lastname: Phalipon
authors.forename: Renaud
authors.initials: R
authors.lastname: Quertainmont
authors.forename: Isabelle
authors.initials: I
authors.lastname: Salmon
authors.forename: Philippe
authors.initials: P
authors.lastname: Sansonetti
authors.forename: Abdelmounaaïm
authors.initials: A
authors.lastname: Allaoui
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000378:metabolism; D002460:Cell Line; D018014:Gene Transfer Techniques; D053590:Interleukin 1 Receptor Antagonist Protein / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism*; D016753:Interleukin-10 / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009000:Monocytes / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D018410:Pneumonia, Bacterial / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D011650:Pulmonary Alveoli / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000378:metabolism*; D020545:Respiratory Mucosa / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D012763:Shigella flexneri / Q000235:genetics* / Q000276:immunology* / Q000472:pathogenicity; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000096:biosynthesis
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D053590:Interleukin 1 Receptor Antagonist Protein; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10