Project Abstracts - CMAI

Mark Wallet, PhD, co-Investigator, University of Florida
Todd Brusko, PhD, co-Investigator, University of Florida
Jing Chen, PhD, co-Investigator, University of Florida
Naohiro Terada, MD, PhD, co-Investigator, University of Florida
Alexei Savinov, MD, co-Investigator, Sanford Research/USD

Start Date: September 30, 2014
End Date: June 30, 2019

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Abstract

The development of Type 1 Diabetes (T1D) relies on complex interrelationships between cells of the immune system [e.g., Dendritic Cells (DC), CD8+ T Cells] and genes imparting susceptibility or resistance to the disease that underlie the autoimmune destruction of insulin producing pancreatic β cells.  While a broad body of evidence certainly exists to support this notion (and we ourselves believe it true), the exact mechanism by which autoimmune β cell destruction is facilitated remains unclear.  In addition, the relative contributions of each facet ([i.e., cells, genes) play in the process remain, to a large extent, unknown.  Mechanistic studies of T1D-associated susceptibility alleles are complicated by polygenic inheritance such that no two individuals are truly alike.  Hence, studies are severely hampered by a lack of power in populations, and the inability to isolate the functional impact of a variant to a specific cell type.  Here we present a solution that focuses on individual alleles using an innovative isogenic model that takes advantage of cutting edge technologies. We have created an experimental platform to study how specific genetic risk variants precipitate immune dysregulation leading to cytotoxic CD8+ T lymphocyte (CTL) activation and β cell destruction. We hypothesize that genetically regulated defects in PTPN22 promote; i) immunogenic DC, ii) TH1 responses, iii) pancreatic vascular inflammation and CTL homing, and iv) pathogenic CTL activity towards β cells coupled with reduced activation induced CTL death: each of these tenants form an aim of this grant. Further, we posit that defects reach full potential when immune cells and endothelial cells are excessively sensitive to activation by endogenous or exogenous factors that stimulate inflammation, thus linking environment and immunogenetics in T1D.

Here we will utilize a novel experimental pipeline where PTPN22R (T1D resistant), PTPN22W (T1D susceptible) or PTPN22 deletion (PTPN22-/-) alleles are carried by isogenic human immune and endothelial cells engineered from induced pluripotent cells. The induced pluripotent cell system allows exquisite control of T1D disease alleles, where the susceptible allele can be replaced by the resistant allele (and vice versa) providing a constant genetic background upon which effects of a single risk allotype can be studied without complicating epistatic effects, in a manner analogous to studies in genetically modified mice. This system proposed here will provide an unprecedented capacity to interrogate molecular and cellular interactions under isogenic conditions to provide mechanistic understanding of how PTPN22 allotypes regulate individual steps of T1D pathogenesis and how those steps interrelate to bring upon T1D onset.  Importantly, this study will also lay the groundwork for future investigations of single or multiple T1D susceptibility genes using this innovative strategy.

Publications

• NADPH Oxidase 2-Derived Reactive Oxygen Species Promote CD8+ T Cell Effector Function
• Guidelines for standardizing T-cell cytometry assays to link biomarkers, mechanisms, and disease outcomes in type 1 diabetes
• Use of Induced Pluripotent Stem Cells to Build Isogenic Systems and Investigate Type 1 Diabetes
• Human islet T cells are highly reactive to preproinsulin in type 1 diabetes
• ENTPD3 Marks Mature Stem Cell Derived Beta Cells Formed by Self-Aggregation in Vitro
• Overexpression of the PTPN22 Autoimmune Risk Variant LYP-620W Fails to Restrain Human CD4(+) T Cell Activation
• Protecting Stem Cell Derived Pancreatic Beta-Like Cells From Diabetogenic T Cell Recognition
• Proinsulin-Reactive CD4 T Cells in the Islets of Type 1 Diabetes Organ Donors
• Observing Islet Function and Islet-Immune Cell Interactions in Live Pancreatic Tissue Slices
• Influence of PTPN22 Allotypes on Innate and Adaptive Immune Function in Health and Disease
• De-coding genetic risk variants in type 1 diabetes
• Towards antigen-specific Tregs for type 1 diabetes: Construction and functional assessment of pancreatic endocrine marker, HPi2-based chimeric antigen receptor
• A hypertension patient derived induced pluripotent stem cell model demonstrates a role for GPER in hypertension risk and development
• Innate inflammation drives NK cell activation to impair Treg activity
• Islet-Immune Interactions in Type 1 Diabetes: The Nexus of Beta Cell Destruction
• Standardizing T-Cell Biomarkers in Type 1 Diabetes: Challenges and Recent Advances
• Neutrophil Cytosolic Factor 1 in Dendritic Cells Promotes Autoreactive CD8(+) T Cell Activation via Cross-Presentation in Type 1 Diabetes
• Crossreactive public TCR sequences undergo positive selection in the human thymic repertoire
• Application of a Genetic Risk Score to Racially Diverse Type 1 Diabetes Populations Demonstrates the Need for Diversity in Risk-Modeling
• The Role of NOD Mice in Type 1 Diabetes Research: Lessons from the Past and Recommendations for the Future
• Mitochondrial Reactive Oxygen Species and Type 1 Diabetes
• New Pharmacogenomics Research Network: An Open Community Catalyzing Research and Translation in Precision Medicine
• The Type 1 Diabetes-Resistance Locus Idd22 Controls Trafficking of Autoreactive CTLs into the Pancreatic Islets of NOD Mice
• Avidity and Bystander Suppressive Capacity of Human Regulatory T Cells Expressing De Novo Autoreactive T-Cell Receptors in Type 1 Diabetes
• Isogenic Cellular Systems Model the Impact of Genetic Risk Variants in the Pathogenesis of Type 1 Diabetes
• A Pathologist’s Perspective on Induced Pluripotent Stem Cells
• Type I Interferon is a Catastrophic Feature of the Diabetic Islet Microenvironment
• T cells display mitochondria hyperpolarization in human type 1 diabetes
• Self-Transducible Bimodal PDX1-FOXP3 Protein Lifts Insulin Secretion and Curbs Autoimmunity, Boosting Tregs in Type 1 Diabetic Mice
• Type 1 Interferons Potentiate Human CD8(+) T-Cell Cytotoxicity Through a STAT4- and Granzyme B-Dependent Pathway
• Plasmacytoid and conventional dendritic cells cooperate in crosspriming AAV capsid-specific CD8(+) T cells
• Islet-Derived CD4 T Cells Targeting Proinsulin in Human Autoimmune Diabetes
• Interferon-γ Limits Diabetogenic CD8+ T-Cell Effector Responses in Type 1 Diabetes
• Concise Review: Induced Pluripotent Stem Cell Research in the Era of Precision Medicine
• Intestinal Epithelial Cell Regulation of Adaptive Immune Dysfunction in Human Type 1 Diabetes
• Genetic risk analysis of a patient with fulminant autoimmune type 1 diabetes mellitus secondary to combination ipilimumab and nivolumab immunotherapy
• Tissue distribution and clonal diversity of the T and B cell repertoire in type 1 diabetes
• Analysis of self-antigen specificity of islet-infiltrating T cells from human donors with type 1 diabetes
• Pancreas-enriched miRNAs are altered in the circulation of subjects with diabetes: a pilot cross-sectional study
• Loss of Peripheral Protection in Pancreatic Islets by Proteolysis-Driven Impairment of VTCN1 (B7-H4) Presentation Is Associated with the Development of Autoimmune Diabetes
• Transgenic Overexpression of Tissue-Nonspecific Alkaline Phosphatase (TNAP) in Vascular Endothelium Results in Generalized Arterial Calcification
• Distinct differences in the responses of the human pancreatic β-cell line EndoC-βH1 and human islets to proinflammatory cytokines
• Reply to Gurgul-Convey and Lenzen: Cytokines, nitric oxide, and β-cells
• Do β-cells generate peroxynitrite in response to cytokine treatment?
• How the location of superoxide generation influences the β-cell response to nitric oxide
• Metabolic abnormalities in the pathogenesis of type 1 diabetes
• Use of chemical probes to detect mitochondrial ROS by flow cytometry and spectrofluorometry