Targeting the Trimolecular Complex for Immune Intervention. Aaron Michels MD

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1 Targeting the Trimolecular Complex for Immune Intervention Aaron Michels MD

2 Disclosures Research Grant from Novartis. Research Grant from NovoNordisk.

3 Take Home Points Type 1 diabetes is an immunologic disease. It is a predictable disease increasing in incidence. Maintaining beta cell function at the time of diagnosis is a goal. Safe & specific immune therapies are needed for prevention and ultimately a cure.

4 T1D incidence is rising 3-5% per year Due to environmental cause(s)? Incidence /100,000/ yr in children aged 0-14 Courtesy of of Marian Rewers

5 Type 1 Diabetes is Predictable (>2 positive islet autoantibodies) Probability of progressing to diabetes (%) Probability of progressing to diabetes (%) Follow-up from seroconversion Follow-up from seroconversion (years) (years) Colorado Finland Germany Ziegler et al. JAMA 2013

6 Type 1 Diabetes Immune mediated Increasing Incidence Predictable PREVENTION

7 Natural History of Type 1 Diabetes ENVIRONMENTAL TRIGGER? AUTOIMMUNITY AUTOANTIBODIES BETA CELL MASS GENETIC PREDISPOSITION INSULITIS BETA CELL INJURY PRE - DIABETES CLINICAL ONSET DIABETES TIME

8 A New Molecular Target for Type 1 Diabetes

9 6.50 Concannon et al NEJM HLA Insulin production & metabolism Locus Immunity β cell apoptosis protection Unknown function

10 Human Chromosome 6 Class II Class III Class I DP DQ DR B C A Allele: Haplotype: DRB1*0401 DRB1*0401 DQB1*0302 Genotype: DRB1*0401 DQB1*0302 DRB1*0301 DQB1*0201

11 T cell Recognition of Antigen on an APC Antigen Endocytosis CD4 + T cell APC T Cell Receptor MHC II Peptide Trimolecular Complex

12 The Trimolecular Complex AA Peptide Side Chains TCR MHC PEPTIDE INS B:9-23 MHC Peptide

13 Insulin Approach 1: Using small drug-like molecules to prevent diabetes Insulin Side Chains HLA

14 Screening Small Drug-like Molecules with a Supercomputer Michels, et al. Journal of Immunology, 2011.

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16 Methyldopa (Aldomet) Clinically wellestablished drug used to treat hypertension & pregnancy induced hypertension for the last 50 years. Pregnancy class B. Blocks DQ8 antigen presentation. methyldopa

17 Methyldopa Blocks Insulin Presentation 250 T cell response in IL-2 (pg/ml) Background Insulin Methyldopa Concentration (Molar)

18 Methyldopa Blocks Insulin Presentation in Mice T Drug a t DQ8 Mice Splenocytes or Blood Culture with insulin & T cell Readout DQ8 Presentation (arbitrary units) Control Methyldopa 165uM 82.5uM Insulin Concentration

19 Phase 1b Clinical Trial: Methyldopa in Recent Onset Type 1 Diabetes Inclusion Criteria: Ages Type 1 diabetes < 2 years duration HLA-DQ8 present Residual insulin production (C-peptide > 0.1ng/mL) Open label, single-center, n=20 participants Phase 1b dose escalation study (NCT ): Baseline 500mg BID 500mg TID 1000mg TID Stop Therapy, Follow up Primary Outcome: Antigen Presentation Assay weeks Drug t Culture with antigen + DQ8 DR4 Readout for each T cell HLA-DQ8 T1D Patients Blood Engineered T cells

20 Targeting Specific MHC Class II Peptide Presentation Autoimmune Response Autoreactive T cell No activation DQ2 X APC Normal Immune Response Memory T cell Activation

21 Second Approach Why do people not develop type 1 diabetes? How do protective HLA alleles provide protection from diabetes?

22 Approach 2: Insulin vaccine to prevent diabetes Goal:

23 Insulin Stadinski, et al. PNAS Michels, et al. J Clinical Immun 2013.

24 Back to the Hotdog Stand Non-Diabetic Diabetic

25 A novel insulin B chain peptide H S 9 L E V 9 B:9-23 B:9-23 (B22E) A L Y 16 L V C E G β57ser 23 G R E p9e α76arg IA g7 -GAD

26 New-Onset T1D patients respond to the insulin peptide IFN-γ Elispots /10 6 PBMCs

27 Non-diabetic Controls respond to the insulin peptide IFN-γ Elispots /10 6 PBMCs IL10 Elispots /10 6 PBMCs IL10 Elispots /10 6 PBMCs

28 Foxp3 Novel Insulin B chain peptide induces protective responses in mice & humans Native Peptide Novel Peptide CD25

29 Develop a vaccine to return the insulin immune response back to normal Goal:

30 Summary The trimolecular complex plays a pivotal role in T1D development. TCR MHC PEPTIDE HLA-DQ8 confers genetic risk for T1D and is remarkably amenable to small molecule targeting. Understanding the molecular basis for insulin specific T cell activation may lead to safe & specific prevention therapies for T1D.

31 Acknowledgements Barbara Davis Center: Michels Lab: Kristen McDaniel Stephanie Case Carol Kiekhaefer Aimon Alkanani Peter Gottlieb Lisa Fitzgerald-Miller Maki Nakayama Melanie Stumpf National Jewish Health: John Kappler Shaodong Dai Fran Crawford University of Florida: David Ostrov Mark Atkinson Clive Wasserfall Funding Agencies: Howard Davidson Tomasz Sosinowski Anita Hohenstein Marian Rewers Liping Yu Janet Snell-Bergeon Li Zhang JDRF

32 HALT-DM