title: Toll-like receptor 7 stimulation promotes autoimmune diabetes in the NOD mouse.
abstract: OBJECTIVE
  The role of Toll-like receptor 7 (TLR7), a sensor of viral and self RNA, in promoting autoimmune diabetes remains unclear. Our goal was to determine the effect of TLR7 stimulation on the priming and activation of diabetogenic CD8(+) T cells.
  
  
  METHODS
  We explored the effects of CL097 (TLR7/8 agonist) and immunoregulatory sequence 661 (IRS661, TLR7 inhibitor) on bone marrow-derived dendritic cells (BMDCs), diabetogenic CD8(+) T cell function and autoimmune diabetes onset in NOD and 8.3 NOD T cell receptor transgenic mice (8.3 NOD mice).
  
  
  RESULTS
  TLR7 stimulation of NOD BMDCs increased activation and production of proinflammatory cytokines. In vivo administration of CL097 activated T cells and dendritic cells and increased levels of proinflammatory cytokines and type 1/2 IFNs in NOD mice. In vivo antigen-specific cytotoxicity studies revealed enhanced cytotoxicity against islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP, an islet autoantigen) peptide pulsed targets in NOD mice treated with CL097 plus CD40 agonist. This combination treatment accelerated the onset of autoimmune diabetes in 8.3 NOD mice. Likewise, topical treatment of NOD mice with a TLR7 agonist accelerated diabetes onset. Spontaneous disease in 8.3 NOD mice and accelerated disease in CL097+CD40 agonist-treated 8.3 NOD mice were delayed by IRS661 treatment, which is associated with inhibition of the endogenous upregulation of IFN-α levels within the pancreatic lymph nodes.
  
  
  CONCLUSIONS
  TLR7 stimulation accelerates the spontaneous onset of autoimmune diabetes in 8.3 NOD and NOD mice. Conversely, TLR7 inhibition prevents the early events associated with diabetogenesis.
authors.affiliation: Department of Dermatology and Skin Science, Child and Family Research Institute, The University of British Columbia, 950 West 28th Avenue, Vancouver, BC, Canada V5Z 4H4.
authors.forename: A S
authors.initials: AS
authors.lastname: Lee
authors.forename: M
authors.initials: M
authors.lastname: Ghoreishi
authors.forename: W K
authors.initials: WK
authors.lastname: Cheng
authors.forename: T-Y E
authors.initials: TY
authors.lastname: Chang
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Zhang
authors.forename: J P
authors.initials: JP
authors.lastname: Dutz
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D001854:Bone Marrow Cells / Q000166:cytology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D019013:CD40 Antigens / Q000494:pharmacology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D003920:Diabetes Mellitus / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D004195:Disease Models, Animal; D007093:Imidazoles / Q000494:pharmacology; D016898:Interferon-alpha / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D051379:Mice; D016688:Mice, Inbred NOD; D008822:Mice, Transgenic; D011804:Quinolines / Q000494:pharmacology; D051199:Toll-Like Receptor 7 / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*
chemical_list: D019013:CD40 Antigens; C547051:CL097 compound; D016207:Cytokines; D007093:Imidazoles; D016898:Interferon-alpha; D008562:Membrane Glycoproteins; D011804:Quinolines; C477038:Tlr7 protein, mouse; D051199:Toll-Like Receptor 7