Who gets the autoimmune disease Type 1 diabetes, and why? 35 years of Type 1 diabetes immunology research – an autoimmune disease model emerges How genes and environment may come together in the “perfect storm” Devising new immunological approaches for translation into therapies 35 years of Type 1 diabetes immunology research – an autoimmune disease model emerges How genes and environment may come together in the “perfect storm” Devising new immunological approaches for translation into therapies Mark Peakman King’s College London Mark Peakman King’s College London

Type 1 diabetes 1921; universally fatal; discovery of insulin Diabetic complications (renal failure, blindness, early cardiovascular disease) due to chronic hyperglycaemia Diabetes costs NHS ~£8-10 billion (Type 1 diabetes £2-5b) “Western Europe: 15,000 new cases in ,400 in 2020 Incidence to double in children <5 years…” No known cure or spontaneous remission Type 1 diabetes 1922 Banting Marjorie Best

InsulinT lymphocytes (CD3) Background I: pathology At diagnosis >80% of islets destroyed

John Todd and Linda Wicker, Cambridge Background II: Large genome-wide studies Pinpoint variants of normal genes that are more frequent in diabetes

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: immune pathogenesis HLA I Pro- inflammatory cytokines CTL T Cytotoxic Epitope discovery Insulin

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: immune pathogenesis HLA I Pro- inflammatory cytokines CTL T Cytotoxic Epitope discovery GENE SET 1: Ag presentation to T cells Insulin

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: immune pathogenesis HLA I CTL IL-10 T Cytotoxic GENE SET 2: Immune regulation Anti- inflammatory cytokines Insulin

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: immune pathogenesis HLA I CTL IL-10 T Cytotoxic GENE SET 3: Pathogen susceptibility Insulin

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: immune pathogenesis HLA I CTL IL-10 T Cytotoxic GENE SET 3: Pathogen susceptibility GENE SET 1: Ag presentation to T cells GENE SET 2: Immune regulation Insulin

GENE SET 1: Ag presentation to T cells T Cytotoxic β cell HLA-A2+ human islets with 1E6 clone A2+ islets/control clone A2- islets/1E6 clone T cytotoxic cells targeting insulin kill human β-cells. Are these cells in the islets where β-cells are killed? T cytotoxic cells targeting insulin kill human β-cells. Are these cells in the islets where β-cells are killed? Epitope discovery HLA

Coppieters et al, JEM, 2012 Insulin- specific T cells In situ staining for antigen- specific T cells

GENE SET 1: Ag presentation to T cells T Cytotoxic β cell A2+ human islets with 1E6 clone A2+ islets/control clone A2- islets/1E6 clone T cytotoxic cells targeting insulin kill human β-cells. How does this interaction look at the molecular level? T cytotoxic cells targeting insulin kill human β-cells. How does this interaction look at the molecular level? Crystal

CTL β cell Dissociation constant Kd ~250μM (ie ultra-low vs tumour antigens (~50 μM) or virus (~5 μM)) In press

HLA-A2 (*0201) TcR β-chain α-chain Bulek et al, Nat Imm 2012 Unique features of insulin-specific TCR: Weakest binding affinity to a natural agonist antigen ever described highly peptide-centric binding dominated by hotspots focused on just two amino acids in the peptide β-cell Killer T cell insulin peptide

Major opportunities for cross-reactivity The antigenic peptide that primed killer T cells may not be from insulin originally

GENE SET 2: Immune regulation

No IL-10 response IL-10 response 7.5y Balance of islet-specific T H cells in peripheral blood in Type 1 diabetes is abnormal Candidate genes: CD25, CTLA4, IL-10 Balance of islet-specific T H cells in peripheral blood in Type 1 diabetes is abnormal Candidate genes: CD25, CTLA4, IL-10 GENE SET 2: Immune regulation

GENE SET 3: Pathogen susceptibility

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II HLA I CTL Insulin T Cytotoxic GENE SET 3: Pathogen susceptibility Candidate genes: IFIH1 EBI2 TLR7/TLR8 BACH2 FUT2 Candidate genes: IFIH1 EBI2 TLR7/TLR8 BACH2 FUT2 Sense pathogens: Set “response rheostat” Sense pathogens: Set “response rheostat”

α α β cells 1. Islet 2. Pancreatic lymph node 3. Via blood HLA II Type 1 diabetes: the model HLA I CTL IL-10 T Cytotoxic GENE SET 3: Pathogen susceptibility GENE SET 1: Ag presentation to T cells GENE SET 2: Immune regulation Insulin B Islet cell AAbs

Anti-CD3, transient depletion of T cells Rituximab, anti-CD20, depletes B cells Abatacept, CTLA4-Ig, co-stimulation blockade Therapeutic options in T1D: “immune suppression”

Emergence of the concept of Antigen Specific Immunotherapy (ASI) for autoimmune disease “The administration of auto-antigen in a form or by a route designed to induce or re-establish tolerance to the same antigen or to the target tissues of the autoimmune response” Lead disease setting: clinical allergy (multiple sclerosis) Inject whole proteins or peptides from allergens Good, sustained clinical efficacy Lead disease setting: clinical allergy (multiple sclerosis) Inject whole proteins or peptides from allergens Good, sustained clinical efficacy 24/11/11

Figure 1 Benefit IL-10

Proinsulin peptide immunotherapy Monthly i.d. injections of proinsulin peptide x 3; 10, 100 and 1000μg per dose IL-10 (SI) ** 10  g placebo month of study * 5µM 10µM Induction of IL-10 response to proinsulin peptide C19-A3 after low dose i.d administration in T1D patients No autoantibody increase or induction; no anti-peptide antibodies No pro-inflammatory cytokine induction Improved glycaemic control

036 Peptide administration Month of study Phase Ib (New T1D) Monthly Bi-weekly Developmental programme (Phase I in 2014) Multiple peptides from >1 β-cell antigen

Who gets the autoimmune disease Type 1 diabetes, and why? 35 years of Type 1 diabetes immunology research – an autoimmune disease model emerges Genes and environment come together in the “perfect storm” New immunological approaches for translation into therapies are emerging: an exciting decade ahead 35 years of Type 1 diabetes immunology research – an autoimmune disease model emerges Genes and environment come together in the “perfect storm” New immunological approaches for translation into therapies are emerging: an exciting decade ahead

Funders and collaborators Department of Immunobiology at KCL Clinical collaborators, Guy’s and St Thomas’ NHS Foundation Trust & King’s College Hospital Cardiff University (Colin Dayan); Cambridge University (Catherine Guy, David Dunger, Linda Wicker, John Todd); University of Bristol (Polly Bingley) Funding agencies: Naimit