Keystone Diabetes in Youth Snowmass: Jan 23, 2008 Clinical diabetes and Endocrinology Book on Immunology Diabetes www.barbaradaviscenter.org_ With teaching slides “Monogenic” Type 1 Diabetes • IPEX (Immune Dysfunction/ Polyendocrinopathy/ Enteropathy/ X-Linked) • APS-1 • Insulin Folding Mutations Awaiting Bone Marrow Transplant for child with IPEX syndrome 9 Months IPEX: Immune Dysfunction, Polyendocrinopathy, Enteropathy, X-linked • Scurfin gene (Foxp3/JM2) - Controls Regulatory T Cells! • Approximately 80% of children with syndrome develop diabetes! • Bone marrow transplant can reverse BDC Comparison APS-I and APS-II APS-I APS-II • Onset Infancy • Siblings AIRE gene mutated • Not HLA Associated • Immunodeficiency Asplenism Mucocutaneous Candidiasis • 18% Type 1 DM • 100% anti-interferon Abs • • • • Older Onset Multiple Generations DR3/4 Associated No Defined Immunodeficiency • 20% Type 1 DM APS-I Loss Thymic Tolerance to “Peripheral” Antigens • Knockout of the AIRE gene abrogates expression of many “peripheral antigens” within the thymus such as insulin • IDDM2 locus is insulin gene and Pugliese (Miami) and Polychronakos (Montreal) have shown, protective allele associated with greater thymic insulin messenger RNA. MODEL AIRE Role in Preventing Autoimmunity Autoreactive thymocyte Tolerization of autoreactive thymocyte TCR MHC + Peptide Thymic Medullary Epithelial Cells AIRE Self-peptides from "peripheral" antigens Mathis/Benoist Europium-ELISA completely differentiated APS1 patients from non-APS1 patients, AD and T1D patients. 1.50 1.25 Index of hIFNa Ab 1.00 0.75 0.50 0.25 0.00 -0.25 APS1 non-APS1 Normal Ctrl AD T1D Check List APS-I Visit New Symptoms History New Signs Physical Oral Candidiasis New Antibodies (21-OH, GAD, IA-2) Ca, Pi, Mg Na, K ALT ACTH, TSH, (LH, FSH) HbA1c Blood Smear (Howell-Jolly) Platelet Count Other Eisenbarth GS, Gottlieb PA. New Engl J Med 2004;350:2068-79 Eisenbarth GS, Gottlieb PA. New Engl J Med 2004;350:2068-79 Development of 21-hydroxylase Autoantibodies in Patients with Type 1A Diabetes 1.4 21-ydroxylase AutoAb 1.2 1 0.8 0.6 0.4 0.2 0 -0.2 0 5 10 15 20 25 AGE 30 35 40 45 Proportion AD free by MICA (21OH+ follow-up group) Fraction survival 1.00 5.1/5.1 not 0.75 0.50 p=0.001 0.25 0.00 0.0 2.5 5.0 7.5 Follow-up time 10.0 12.5 Premature Mortality in Patients with Addison’s Disease: A Population-Based Study J clin endocrinol Metab 91:4859, 2006 Percent Dying 6.7 yr follow-up; mean start age 52.8 30 25 20 15 10 5 0 Addison's N=507 deaths of 1675 patients Expected N=199 deaths Peak Cortisol (ug/dl) 21-Hydroxylase Autoantibody Positive Patients 50 40 30 20 10 0 1 10 100 1000 ACTH (pg/ml 10000 PALM ELBOW Transglutam inase Deamidation of Gliadin Peptides increases affinity for DQ2! Figure 1. MZT Twins: Survival analysis of progression to diabetes by age in probands and non-probands 100 90 Percent Not Diabetic 80 70 60 50 P<0.0001 40 Non-proband 30 20 Proband 10 0 0 10 20 30 40 50 60 70 9 3 1 Age Probands n= 83 Non-probands n= 83 51 73 16 45 8 28 1 19 80 Figure 4. Survival analysis of progression to Ab+ or diabetes by age in MZ twin mates 100 90 Percent neither Ab+ nor diabetic 80 70 60 50 40 30 20 10 0 0 10 20 83 70 38 30 40 50 60 Age first positive Ab+ and/or diabetes Non-proband n= 26 15 5 2 70 80 Figure 2. Correlation between the age of onset of diabetes in MZT proband and his/her twin mate (for those twin mates who developed diabetes) Age of Onset in Initially Discordant Twin 60 50 40 30 Li ne of Id e i nt ty p< 0.0001 r2= 0.7083 20 10 0 0 10 20 30 40 Age of Onset in Proband Twin 50 60 J. Noble TERMINOLOGY Allele: Haplotype: Genotype DRB1*0401 DRB1*0401 DQB1*0302 DRB1*0401 DQB1*0302 DRB1*0301 DRB1*02 DQB1*02 DQB1*0402 -chain Leu56 -chain Asp57 BDC BDC DAISY Study Population General population cohort Sibling/offspring cohort screened = 31,881 offspring Enrolled 387 456 384 1,227 high risk moderate risk average-low risk All siblings 51 (7.6%) 111 (17%) 509 53 (14%) 65 (17%) 254 671 372 HLA-defined IDDM risk groups Denver population, n=9,338 IDDM risk by age 20 HLA-DR DQB1 High 1:15 3/4 0201/0302 2.4 Moderate 1:60-1:200 4/x 4/4 3/3 0302/ 0302/ 0201/0201 12.7 3.0 1.4 Average 1:300 3/x 3/4 0201/ 0201/not 0302 12.5 1.0 Lower than 1:300 4/x, 4/4 others /not 0302 6.6 60.4 DAISY 7/96 Frequency % Autoantibody positive (% ) % Autoantibody Positive 100 90 80 70 60 50 40 30 20 10 0 High risk sibling High risk offspring Mod risk sibling Mod risk offspring Low risk sibling Low risk offspring 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Age (y) High risk sib: 49 Mod risk sib: 62 Low risk sib: 221 High risk offsp: 51 Mod risk offsp: 110 Low risk offsp: 506 43 60 216 49 106 477 40 33 26 22 20 14 11 10 8 7 50 45 39 34 30 28 23 19 16 10 198 181 160 139 109 88 66 55 44 34 44 40 33 28 21 19 15 10 8 6 92 83 69 58 49 41 33 27 20 14 430 378 324 271 228 191 153 128 109 89 6 8 27 3 12 72 4 3 24 1 12 52 2 2 19 0 8 38 0 0 0 0 0 0 (% ) A u to a n tib o d y p o s it % A u t o a n t ib o d y P o s it iv e 100 90 80 70 60 50 40 30 20 10 0 H ig h r is k M o d r is k L o w r is k 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Ag e (y) High risk: Mod risk: Low risk: 380 345 295 236 192 169 138 103 75 35 17 441 388 267 186 137 115 100 92 76 59 26 383 326 272 237 211 185 171 154 128 88 55 MHC Haplotype Sharing Increases DR3/4 Sibling Risk Haplotype Determination: Siblings Share Both Haplotypes Siblings Share One Haplotype Siblings Share No Haplotype Family B Family C Family A Haplotypes A B C D A B C D A B C D HLA-A 1 2 29 2 2 68 1 30 2 1 3 31 HLA-DRB1 3 4 4 6 4 8 3 3 3 3 4 4 Diabetic Proband DAISY Sibling Diabetic Proband DAISY Sibling Diabetic Proband DAISY Sibling HLA-A 1 29 1 29 2 30 2 1 1 31 2 3 HLA-DRB1 3 4 3 4 4 3 4 3 3 4 3 4 A C A C A D A C B D A C % Autoantibody Positive 100 Share 2 90 Share 0 or 1 % Diabetic 100 90 80 80 70 70 60 60 50 50 40 40 30 30 20 20 10 10 0 0 0.0 2.5 5.0 7.5 10.0 12.5 15.0 0.0 Age (y) Share 2 Share 0 or 1 2.5 5.0 7.5 10.0 12.5 15. Age (y) ODDS RATIO 7 6 5 4 3 2 IN PT S PN 22 C D 25 12 q2 ER 4 B B 3e PT PN K 2 IA A 03 50 C TL A 4 C D 25 H LA cl as s II 1 Modified from Todd et al. Robust Associations of four new chromosome regions from genome-wide anlayses of type 1 diabetes Nature Genetics June 6 2007