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Immunopathogenesis of Type 1 Diabetes: Approaches to Prevention and Cure. Peter A. Gottlieb, MD George S. Eisenbarth, MD, PhD Jay Skyler, MD + Barbara Davis Center University of Colorado Health Sciences Center + Diabetes Research Institute University of Miami Medical School.
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Immunopathogenesis of Type 1 Diabetes:Approaches to Prevention and Cure Peter A. Gottlieb, MD George S. Eisenbarth, MD, PhD Jay Skyler, MD+ Barbara Davis Center University of Colorado Health Sciences Center +Diabetes Research Institute University of Miami Medical School
Magnitude of Diabetes Worldwide USA • Approximately 6% are diagnosed (90%Type2) • All with Type 1 and 1/3 of Type 2 will require insulin (Expected to Rise significantly) • Cost $100-$140 billion annually Diabetes in Rest of the World • 2 - 25% in different Countries (average 10%) • Incidence rising every year everywhere, especially for Type 2 Diabetes • Disease is still under-diagnosed and delayed in diagnosis • Prevention of pre- type 1 and type 2 diabetes
Incidence Type 1 Diabetesper 100,000 per year Children <=14 Karvonnen et al., Diabetes Care, 23:1516, 2000
Type 1 DM incidence is rising 3-5% /year 1.4 million patients in the U.S. Incidence /100,000/ yr children age 0-14 Rewers
Finland Incidence Type 1 DM/100K 1965-1996 Diabetes Care: 22:1066-1070
Main Points • Type 1 diabetes is an autoimmune disease • It is a predictable disease with different phases • Approaches to prevention and cure are possible. • Combination therapy targeting multiple pathways may hold the greatest hope for prevention and cure.
Progression to Diabetes vs Number of Autoantibodies (GAD, ICA512, Insulin) Percent not Diabetic Years of Follow-up 3 Ab n = 41 17 8 1 2 Abs n = 44 27 15 4 2 1 1 Abs n = 93 23 14 10 6 4 Verge et al, Diabetes 45:926-933, 1996 BDC
DQB1*0402 -chain Leu56 -chain Asp57 BDC
HLA-Defined T1 DM Risk GroupsDAISY, Denver Population, n=21,713
Different haplotypes are associated with T1D in Japanese and Caucasian populations Japanese Caucasian DRB1-DQB1Type 1 diabetes HF1)Type 1 diabetes HF haplotypesusceptibilitysusceptibility DRB1*0405-DQB1*0401 susceptible presentunknown rare DRB1*0901-DQB1*0303 susceptible presentunknown rare DRB1*0301-DQB1*0201 unknown rare susceptible present DRB1*0401-DQB1*0302 unknown rare susceptible present DRB1*1501-DQB1*0602protective present protective present • HF: Haplotype frequency, http://square.umin.ac.jp/JSHI/frame.html
100 80 60 % 40 20 0 I/I I/III III/III IDDM Controls VNTR Class IDDM2 Genotypes in U.S. Caucasians Pugliese et al., J. Autoimm 7: 687- 694, 1994
VNTR alleles affect INS transcription in thymus Thymus INS Transcription cDNA cDNA DNA DNA Predisposing Class I VNTR Protective Class III VNTR Class I VNTR Pancreas INS Transcription Class III VNTR Pugliese et al. Nature Genetics 15:293-297, 1997 Predisposing Class I VNTR Protective Class III VNTR
No Evidence: IDDM 4,6,9,11,16,17,18 (O.R. MHC, DR3/4-DQ8) Adapted from Concannon et al, Diabetes: 54:2995-3001, 2005 BDC
Proportion of Twins Without Diagnosis of DM 1.0 0.8 0.6 0.4 0.2 0.0 0 10 20 30 40 50 6 and younger n= 38 7-10 n= 33 11-14 n= 42 15-24 n= 37 25 and older n= 37 Difference significant (log-rank and gen'ld wilcoxon p= 0.001 , 0.001 ) Years Since DM Diagnosis in Index Twin Redondo, Diabetologia
Type 1a Diabetes: An Autoimmune Disorder • Autoantibodies to islet proteins: insulin, GAD 65, IA-2 (ICA512) • T cell responses to islet proteins • HLA association • Immunosuppressive drugs can ameliorate the disorder – ex. Cyclosporine • Recurrence of autoimmunity in pancreas transplants between monozygotic twins
Prediabetic T cell responses to CD4 epitopes from IA-2b Keleman, Gottlieb et al. 2004. Journal of Immunology.15;172(6):3955-62.
Cytotoxic T-cells from HLA-A*0201 patients with T1D recognize preproIAPP 5-13 ELISPOT analysis of peripheral blood mononuclear responses to preproIAPP5-13 in patients with the correct HLA to recognize the peptide. Diabetes 2003 52:2649
T cell reactivity to CD8 Epitopes from T1D subjects Ouyang, et al, submitted
Natural History of Type 1 Diabetes PUTATIVE ENVIRONMENTAL TRIGGER HUMORAL AUTOANTIBODIES (ICA, IAA, Anti-GAD65, IA2Ab, etc.) BETA CELL MASS GENETIC PREDISPOSITION INSULITIS BETA CELL INJURY CLINICAL ONSET “PRE”-DIABETES DIABETES TIME CELLULAR (T CELL) AUTOIMMUNITY LOSS OF FIRST PHASE INSULIN RESPONSE (IVGTT) GLUCOSE INTOLERANCE (OGTT)
Stochastic Model Non Specific Tx Antigen Specific Tx Immunosuppresive Tx
Primary Prevention • autoantibodies or diabetes as the endpoint • avoidance of environmental agents ? • induction of autoantigen tolerance ? Rewers-BDC
TRIGR 3-yr Follow-up Results Seroconversion to 1+ Autoantibody p=0.043 n=173
NutritionalInterventiontoPrevent • Type 1 Diabetes (NIP– Diabetes) • Plan:Use of an omega 3 fatty acid (Docosahexanoic acid or DHA) to preventthe initial autoimmune process. • DHA supplementation will begin in: • the last trimester of pregnancy • the first 6 months after birth • It will be continued in medium or high risk infants for 3 years.
Dietary Intake – Western Diets The Ratio of n-6 to n-3 Fatty Acids in our diet: 1800’s = 1 or 2 (n-6) to 1 (n-3) Present = 20 or 30 (n-6) to 1 (n-3) High n-3: anti-inflammatory anti-thrombotic hypolipidemic vasodilatory (High n-6 has the opposite effect) (Am J. Clin Nutr. 70, 560-569, 1999)
III) Mechanisms of Action of Omega 3 Fatty Acids • Decrease AA in cell membranes alters PGE 1 and 2 production (inflammatory prostaglandins) • Decrease pro-inflammatory cytokines TNF, IL-1 and IL6 ( efficacy of IL4 and IL10) • Decrease ICAM-1 on monocyte surfaces in humans fed 3g fish oil/dx 21 days ( chronic inflammation) • DHA and /or vit D may haveimportant immune modulating effects in babies at risk for developing T1DM
ENDIT: Kaplan-Meier failure curve - European Nicotinamide Diabetes Intervention Trial (ENDIT) Group Lancet 2004; 363: 925–31
Ongoing or Completed Prevention Trials • TRIGR - Casein Hydrolysate - ongoing (Cow’s Milk Elimination) • NIP - Nutritional Intervention to Prevent T1DM – Starting June, 2006 • DIPP - Nasal Insulin - ongoing • INIT - IntraNasal Insulin Trial • ENDIT - Nicotinamide - Ineffective • DPT-1 - Oral Insulin – May be effective in subgroup - Parenteral - Ineffective • Anti-CD3 and Exanitide- proposed Early stage Late stage
Antigen Specific Therapy • Magic bullet Approach • Targets autoreactive cells • Generates protective cells • Spares rest of immune system • Minimal Toxicity • Timing may be critical to efficacy
Insulin • Beta Cell Specific • Predominant T-cell reactivity islets NOD • Insulin expressed lymphoid tissue by dendritic and macrophage-like cells • Thymic messenger RNA for insulin related to “protective” insulin allele • Proinsulin expression in thymus prevents NOD diabetes
Effect of Insulin Injections on Diabetes & Insulitis Female NOD Mice Atkinson, Diabetes 1991
Prevention of Diabetes with B:9-23 Peptide “Immunization” 100 B:9-23 peptide 80 Tetanus control 60 Percent Not Diabetic 40 20 0 0 10 20 30 40 50 60 Age in Weeks D.Daniel ,D.Wegmann . PNAS,1996
Efficacy of NBI-6024 in animal models with ‘new onset’ Type I diabetes. Figure 3. NBI-6024 Treatment of NOD mice Near Onset of Disease Alleva, et al, Diabetes 2002
APL-specific Th2 cell line transfer NBI-6024-specific Th2 cells adoptively transferred protection in NOD mice Figure 4. From Alleva, et al. Diabetes. 2002 51(7):2126-34.
Mouse BHT-3021 provides significant delayof diabetes onset in hyperglycemic mice at all dosing frequencies BHT-3021 QW BHT-3021 Q2W BHT-3021 Q4W
Treatment of hyperglycemic mice with mouse BHT-3021 restores normoglycemia
DPT-1 Parenteral Study – Time to Diabetes By Treatment 1.0 0.9 0.8 0.7 0.6 Treated Survival Distribution Function 0.5 0.4 Control 0.3 P- Value= 0.796 (Log Rank Test) 0.2 Number at Risk 0.1 169 170 144 131 96 101 69 69 39 40 13 14 Intervention Observation 1 0.0 0 1 2 3 4 5 6 7 Years Followed Observation Intervention STRATA: New Engl J Med 2002; 346:1679
TH1 Cells TH2 Cells TH3 Cells IFN-g, IL-2 IL-4, IL-5, IL-10 TGF-b Protective Cytokines Destructive Cytokines Rationale for Oral Insulin
Oral Antigen Protocol • Initial results appeared to suggest no effect of oral insulin • Secondary analysis suggests that for original cohort (IAA>80) there is delay in onset compared to placebo treated patients. • In fact, the higher the titer of IAA, the greater the protective effect that was observed. • A new trial to confirm these observations is being planned by TrialNet (Start Date – Nov, 2006)
Recent and Ongoing Antigen-specific Immunotherapy Trials in T1DM Prediabetes • Joslin Parenteral Insulin: “Delay” • Schwabing Parenteral Insulin: “Delay” • DPT-1 Parenteral: No Effect • DIPP (intranasal): ? • Melbourne (intranasal): ? • DPT-1 Oral Insulin: Possible for subgroup • Italy/France Oral Insulin: No Effect • Maclaren Oral Insulin: ? • NBI 6024-0003 (Neurocrine) – Phase II Spring, 2007 • B chain – Orban, Joslin - Phase I ? • hGAD s.c. in alum (Diamyd) 20ug dose only • Peptor Heat Shock Protein ? • Proinsulin DNA vaccine (Bayhill) Fall, 2006 New Onset
Secondary Prevention • Goal - induction of diabetes remission and preservation of C-peptide • non-antigen-specific interventions • antigen specific interventions
EDIC: Long Term Benefit of Intensive Treatment • The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions • and Complications Research Group. N Engl J Med 2000;342:381-9.
EDIC: Long Term Benefit of Intensive Treatment • The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions • and Complications Research Group. N Engl J Med 2000;342:381-9.
b-Cell Function and Complications in theDiabetes Control and Complications Trial - Steffes MW, et al. Diabetes Care 26:832–836, 2003
b-Cell Function and Hypoglycemia in theDiabetes Control and Complications Trial - Steffes MW, et al. Diabetes Care 26:832–836, 2003
Cellular Mechanics of Autoimmune Type 1 Diabetes Regenerative Therapies Cellular Therapy MMF DZB Anti-CD3 ATG Target b NK b b Tc1 CD4CD25 b Effector Cells b b b B MO Tr1 Rituximab Th1 Th2 Regulatory Cells Th3 Insulin GAD IGRP HSP60 NKT
Lack of Effect of BCG Vaccination in New Onset T1D subjects Fasting C-Peptide Stimulated C-Peptide Age < 12 >=12 Adapted from Allen, et al, Diabetes Care 1999, 22:1703-07