title: Insulin B chain 9-23 gene transfer to hepatocytes protects from type 1 diabetes by inducing Ag-specific FoxP3+ Tregs.
abstract: Antigen (Ag)-specific tolerance in type 1 diabetes (T1D) in human has not been achieved yet. Targeting lentiviral vector (LV)-mediated gene expression to hepatocytes induces active tolerance toward the encoded Ag. The insulin B chain 9-23 (InsB9-23) is an immunodominant T cell epitope in nonobese diabetic (NOD) mice. To determine whether auto-Ag gene transfer to hepatocytes induces tolerance and control of T1D, NOD mice were treated with integrase-competent LVs (ICLVs) that selectively target the expression of InsB9-23 to hepatocytes. ICLV treatment induced InsB9-23-specific effector T cells but also FoxP3(+) regulatory T cells (Tregs), which halted islet immune cell infiltration, and protected from T1D. Moreover, ICLV treatment combined with a single suboptimal dose of anti-CD3 monoclonal antibody (mAb) is effective in T1D reversal. Splenocytes from LV.InsB9-23-treated mice, but not from LV.OVA (ovalbumin)-treated control mice, stopped diabetes development, demonstrating that protection is Ag-specific. Depletion of CD4(+)CD25(+)FoxP3(+) T cells led to diabetes progression, indicating that Ag-specific FoxP3(+) Tregs mediate protection. Integrase-defective LVs (IDLVs).InsB9-23, which alleviate the concerns for insertional mutagenesis and support transient transgene expression in hepatocytes, were also efficient in protecting from T1D. These data demonstrate that hepatocyte-targeted auto-Ag gene expression prevents and resolves T1D and that stable integration of the transgene is not required for this protection. Gene transfer to hepatocytes can be used to induce Ag-specific tolerance in autoimmune diseases.
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy. Vita-Salute San Raffaele University, Milan 20132, Italy.
authors.forename: Mahzad
authors.initials: M
authors.lastname: Akbarpour
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy.
authors.forename: Kevin S
authors.initials: KS
authors.lastname: Goudy
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Cantore
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Russo
authors.affiliation: Pathology Unit, Department of Oncology, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Sanvito
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy. Vita-Salute San Raffaele University, Milan 20132, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Naldini
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Annoni
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy, Division of Regenerative Medicine, Stem Cells and Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan 20132, Italy. Vita-Salute San Raffaele University, Milan 20132, Italy. Department of Pediatrics, Stanford School of Medicine, Stanford, CA 94305, USA. mg1@stanford.edu.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Roncarolo
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology*; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology* / Q000517:prevention & control / Q000628:therapy*; D018450:Disease Progression; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D007108:Immune Tolerance; D007328:Insulin / Q000235:genetics / Q000627:therapeutic use*; D019426:Integrases / Q000378:metabolism; D016086:Lentivirus / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology; D051379:Mice; D010446:Peptide Fragments / Q000235:genetics / Q000627:therapeutic use*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D019076:Transgenes
chemical_list: D000941:Antigens; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D007328:Insulin; D010446:Peptide Fragments; C097877:insulin B (9-23); D019426:Integrases