247-OR: ADA Presidents’ Select Abstract: Detection of T-Cells Reactive to Hybrid Insulin Peptides in Subjects at Risk for Type 1 Diabetes

Type 1 diabetes in children is heralded by a preclinical phase defined by circulating autoantibodies to pancreatic islet antigens. How islet autoimmunity is initiated and then progresses to clinical diabetes remains poorly understood. Only one study has reported gene expression in specific immune cells of at-risk children, associated with progression to islet autoimmunity. We analysed gene expression by RNAseq in CD4+ and CD8+ T cells, NK cells and B cells, and chromatin accessibility by ATACseq in CD4+ T cells, in five genetically at-risk children with islet autoantibodies who progressed to diabetes over a median of 3 years (‘Progressors’) compared to five children matched for sex, age and HLA-DR who had not progressed (‘Non-progressors). In Progressors, differentially expressed genes (DEGs) were largely confined to CD4+ T cells and enriched for cytotoxicity-related genes/pathways. Several top-ranked DEGs were validated in a semi-independent cohort of 13 Progressors and 11 Non-progressors. Flow cytometry confirmed progression was associated with expansion of CD4+ cells with a cytotoxic phenotype. By ATAC-seq, progression was associated with reconfiguration of regulatory chromatin regions in CD4+ T cells, some linked to differentially expressed cytotoxicity-related genes. Our findings suggest that cytotoxic CD4+ T cells play a role in promoting progression to type 1 diabetes.

Download Full-text

Cytotoxicity-related Gene Expression and Chromatin Accessibility Define a Subset of CD4+ T Cells that Mark Progression to Type 1 Diabetes

10.2337/figshare.17185898 ◽

2022 ◽

Author(s):

Naiara G. Bediaga ◽

Alexandra L. Garnham ◽

Gaetano Naselli ◽

Esther Bandala-Sanchez ◽

Natalie L. Stone ◽

...

Keyword(s):

Gene Expression ◽

At Risk ◽

T Cells ◽

Type 1 Diabetes ◽

Chromatin Accessibility ◽

Differentially Expressed ◽

Islet Autoimmunity ◽

Preclinical Phase ◽

At Risk Children

Type 1 diabetes in children is heralded by a preclinical phase defined by circulating autoantibodies to pancreatic islet antigens. How islet autoimmunity is initiated and then progresses to clinical diabetes remains poorly understood. Only one study has reported gene expression in specific immune cells of at-risk children, associated with progression to islet autoimmunity. We analysed gene expression by RNAseq in CD4+ and CD8+ T cells, NK cells and B cells, and chromatin accessibility by ATACseq in CD4+ T cells, in five genetically at-risk children with islet autoantibodies who progressed to diabetes over a median of 3 years (‘Progressors’) compared to five children matched for sex, age and HLA-DR who had not progressed (‘Non-progressors). In Progressors, differentially expressed genes (DEGs) were largely confined to CD4+ T cells and enriched for cytotoxicity-related genes/pathways. Several top-ranked DEGs were validated in a semi-independent cohort of 13 Progressors and 11 Non-progressors. Flow cytometry confirmed progression was associated with expansion of CD4+ cells with a cytotoxic phenotype. By ATAC-seq, progression was associated with reconfiguration of regulatory chromatin regions in CD4+ cells, some linked to differentially expressed cytotoxicity-related genes. Our findings suggest that cytotoxic CD4+ T cells play a role in promoting progression to type 1 diabetes.

Download Full-text

Circulating β cell‐specific CD8 + T cells restricted by high‐risk HLA class I molecules show antigen experience in children with and at risk of type 1 diabetes

Clinical & Experimental Immunology ◽

10.1111/cei.13391 ◽

2019 ◽

Vol 199 (3) ◽

pp. 263-277 ◽

Cited By ~ 5

Author(s):

L. Yeo ◽

I. Pujol‐Autonell ◽

R. Baptista ◽

M. Eichmann ◽

D. Kronenberg‐Versteeg ◽

...

Keyword(s):

At Risk ◽

T Cells ◽

Type 1 Diabetes ◽

High Risk ◽

Cd8 T Cells ◽

Hla Class I ◽

Class I ◽

Β Cell ◽

Hla Class I Molecules

Download Full-text

Myeloid - derived suppressor cells in Type 1 diabetes are an expanded population exhibiting diverse T-cell suppressor mechanisms

PLoS ONE ◽

10.1371/journal.pone.0242092 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0242092

Author(s):

Anna Grohová ◽

Klára Dáňová ◽

Irena Adkins ◽

Zdeněk Šumník ◽

Lenka Petruželková ◽

...

Keyword(s):

At Risk ◽

T Cells ◽

Type 1 Diabetes ◽

Autoimmune Diseases ◽

Suppressor Cells ◽

Cell Contact ◽

Myeloid Derived Suppressor Cells ◽

Healthy Donors

Myeloid-derived suppressor cells (MDSC) represent a heterogeneous group of immature myeloid cells with immunoregulatory function in cancer and autoimmune diseases. In humans, two subsets of MDSC were determined based on the characteristic surface markers, monocytic MDSC (M-MDSC) and granulocytic MDSC (G-MDSC). Expansion of MDSC has been reported in some murine models and patients with autoimmune diseases and their immune-suppressive properties were characterized. However, the exact role of MDSC in the pathogenesis of autoimmune diseases is more complex and/or controversial. In type 1 diabetes mellitus (T1D), the increased frequency of MDSC was found in the blood of T1D patients but their suppressor capacity was diminished. In our study, we assessed the role of M-MDSC in the pathogenesis of T1D and showed for the first time the increased frequency of M-MDSC not only in the blood of T1D patients but also in their at-risk relatives compared to healthy donors. T1D patients with inadequate long term metabolic control showed an elevation of M-MDSC compared to patients with better disease control. Furthermore, we described the positive correlation between the percentage of M-MDSC and Th17 cells and IFN-γ producing T cells in T1D patients and their at-risk relatives. Finally, we found that the ability of M-MDSC to suppress autologous T cells is efficient only at the high MDSC: T cells ratio and dependent on cell-cell-contact and TGF-β production. Our data show that the engagement of MDSC in the pathogenesis of T1D is evident, yet not entirely explored and more experiments are required to clarify whether MDSC are beneficial or harmful in T1D.

Download Full-text

Mapping T Cell Responses to Native and Neo-Islet Antigen Epitopes in at Risk and Type 1 Diabetes Subjects

Frontiers in Immunology ◽

10.3389/fimmu.2021.675746 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sefina Arif ◽

Irma Pujol-Autonell ◽

Yogesh Kamra ◽

Evangeline Williams ◽

Norkhairin Yusuf ◽

...

Keyword(s):

At Risk ◽

T Cells ◽

Type 1 Diabetes ◽

T Cell ◽

Single Cell ◽

T Cell Responses ◽

Cell Reactivity ◽

Cell Responses ◽

T Cell Reactivity

AimsRecent studies highlight the potentially important role of neoepitopes in breaking immune tolerance in type 1 diabetes. T cell reactivity to these neoepitopes has been reported, but how this response compares quantitatively and phenotypically with previous reports on native epitopes is not known. Thus, an understanding of the relationship between native and neoepitopes and their role as tolerance breakers or disease drivers in type 1 diabetes is required. We set out to compare T cell reactivity and phenotype against a panel of neo- and native islet autoantigenic epitopes to examine how this relates to stages of type 1 diabetes development.MethodsFifty-four subjects comprising patients with T1D, and autoantibody-positive unaffected family members were tested against a panel of neo- and native epitopes by ELISPOT (IFN-γ, IL-10, and IL-17). A further subset of two patients was analyzed by Single Cell Immune Profiling (RNAseq and TCR α/β) after stimulation with pools of native and neoepitope peptides.ResultsT cell responses to native and neoepitopes were present in patients with type 1 diabetes and at-risk subjects, and overall, there were no significant differences in the frequency, magnitude, or phenotype between the two sets of peptide stimuli. Single cell RNAseq on responder T cells revealed a similar profile in T1D patients stimulated with either neo- or native epitopes. A pro-inflammatory gene expression profile (TNF-α, IFN-γ) was dominant in both native and neoepitope stimulated T cells. TCRs with identical clonotypes were found in T cell responding to both native and neoepitopes.Conclusion/InterpretationThese data suggest that in peripheral blood, T cell responses to both native and neoepitopes are similar in terms of frequency and phenotype in patients with type 1 diabetes and high-risk unaffected family members. Furthermore, using a combination of transcriptomic and clonotypic analyses, albeit using a limited panel of peptides, we show that neoepitopes are comparable to native epitopes currently in use for immune-monitoring studies.

Download Full-text

Cytotoxicity-related Gene Expression and Chromatin Accessibility Define a Subset of CD4+ T Cells that Mark Progression to Type 1 Diabetes

10.2337/figshare.17185898.v1 ◽

2022 ◽

Author(s):

Naiara G. Bediaga ◽

Alexandra L. Garnham ◽

Gaetano Naselli ◽

Esther Bandala-Sanchez ◽

Natalie L. Stone ◽

...

Keyword(s):

Gene Expression ◽

At Risk ◽

T Cells ◽

Type 1 Diabetes ◽

Chromatin Accessibility ◽

Differentially Expressed ◽

Islet Autoimmunity ◽

Preclinical Phase ◽

At Risk Children

Type 1 diabetes in children is heralded by a preclinical phase defined by circulating autoantibodies to pancreatic islet antigens. How islet autoimmunity is initiated and then progresses to clinical diabetes remains poorly understood. Only one study has reported gene expression in specific immune cells of at-risk children, associated with progression to islet autoimmunity. We analysed gene expression by RNAseq in CD4+ and CD8+ T cells, NK cells and B cells, and chromatin accessibility by ATACseq in CD4+ T cells, in five genetically at-risk children with islet autoantibodies who progressed to diabetes over a median of 3 years (‘Progressors’) compared to five children matched for sex, age and HLA-DR who had not progressed (‘Non-progressors). In Progressors, differentially expressed genes (DEGs) were largely confined to CD4+ T cells and enriched for cytotoxicity-related genes/pathways. Several top-ranked DEGs were validated in a semi-independent cohort of 13 Progressors and 11 Non-progressors. Flow cytometry confirmed progression was associated with expansion of CD4+ cells with a cytotoxic phenotype. By ATAC-seq, progression was associated with reconfiguration of regulatory chromatin regions in CD4+ cells, some linked to differentially expressed cytotoxicity-related genes. Our findings suggest that cytotoxic CD4+ T cells play a role in promoting progression to type 1 diabetes.

Download Full-text