title: An oral vaccine for type 1 diabetes based on live attenuated Salmonella.
abstract: Type 1 diabetes (T1D) is a metabolic disease that is initiated by the autoimmune destruction of pancreatic insulin-producing beta cells that is accompanied by the development of antigen-specific antibodies and cytotoxic T lymphocytes (CTLs). Several studies have shown that vaccination with diabetic autoantigens provides some protection against this process. In this report we describe a new oral vaccine that utilizes live attenuated Salmonella for simultaneous delivery of autoantigens in conjunction with immunomodulatory cytokine genes to immune cells in the gut mucosa. Recent data showed that live attenuated Salmonella is a safe, simple and effective vector for expression of antigens and cytokines by antigen-presenting cells (APCs) of gut-associated lymphatic tissue (GALT). This novel strategy was tested by fusion of the diabetic autoantigen preproinsulin with Salmonella secretory effector protein (SseF) of pathogenicity island-2 (SPI2). In this way the autoantigen is only expressed inside the host immune cells and translocated to the host cell cytosol. In addition Salmonella was used to deliver the gene for the immunomodulatory cytokine transforming growth factor beta (TGFβ) for host cell expression. Oral co-vaccination of 8 week-old non-obese diabetic (NOD) mice with three weekly doses of both the autoantigen and cytokine significantly reduced the development of diabetes, improved the response to glucose challenge, preserved beta cell mass, and reduced the severity of insulitis compared with controls and autoantigen alone. Combination therapy also resulted in increased circulating levels of IL10 four weeks post-vaccination and IL2 for 12 weeks post-vaccination, but without effect on proinflammatory cytokines IL6, IL12(p70), IL17 and IFNγ. However, in non-responders there was a significant rise in IL12 compared with responders. Future studies will examine the mechanism of this vaccination strategy in more detail. In conclusion, Salmonella-based oral vaccines expressing autoantigens combined with imunomodulatory cytokines appears to be a promising therapy for prevention of T1D.
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA; Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.
authors.forename: Mohamed I
authors.initials: MI
authors.lastname: Husseiny
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Rawson
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kaye
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA.
authors.forename: Indu
authors.initials: I
authors.lastname: Nair
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Todorov
authors.affiliation: Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Hensel
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA.
authors.forename: Fouad
authors.initials: F
authors.lastname: Kandeel
authors.affiliation: Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of City of Hope, Duarte, CA 91010-3000, USA. Electronic address: kferreri@coh.org.
authors.forename: Kevin
authors.initials: K
authors.lastname: Ferreri
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001324:Autoantigens / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology; D002460:Cell Line; D003922:Diabetes Mellitus, Type 1 / Q000517:prevention & control*; D005260:Female; D005822:Genetic Vectors; D007328:Insulin / Q000235:genetics / Q000276:immunology*; D007378:Interleukins / Q000276:immunology; D008565:Membrane Proteins / Q000276:immunology; D016688:Mice, Inbred NOD; D011498:Protein Precursors / Q000235:genetics / Q000276:immunology*; D012475:Salmonella; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000276:immunology; D014612:Vaccines / Q000276:immunology*
chemical_list: D001324:Autoantigens; D001426:Bacterial Proteins; D007328:Insulin; D007378:Interleukins; D008565:Membrane Proteins; D011498:Protein Precursors; C440638:SPI-2 protein, Salmonella; D016212:Transforming Growth Factor beta; D014612:Vaccines; C013737:preproinsulin
keywords: Autoantigens; Immunotherapy; Preproinsulin; Salmonella pathogenicity island 2 (SPI2); Transforming growth factor-beta; Type 1 diabetes