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Wang L, Yang S, Zhu G, Li J, Meng G, Chen X, Zhang M, Wang S, Li X, Pan Y, Huang Y, Wang L, Wu Y. Immunopeptidome mining reveals a novel ERS-induced target in T1D. Cell Mol Immunol 2024; 21:604-619. [PMID: 38689020 PMCID: PMC11143349 DOI: 10.1038/s41423-024-01150-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 03/03/2024] [Indexed: 05/02/2024] Open
Abstract
Autoreactive CD8+ T cells play a key role in type 1 diabetes (T1D), but the antigen spectrum that activates autoreactive CD8+ T cells remains unclear. Endoplasmic reticulum stress (ERS) has been implicated in β-cell autoantigen generation. Here, we analyzed the major histocompatibility complex class I (MHC-I)-associated immunopeptidome (MIP) of islet β-cells under steady and ERS conditions and found that ERS reshaped the MIP of β-cells and promoted the MHC-I presentation of a panel of conventional self-peptides. Among them, OTUB258-66 showed immunodominance, and the corresponding autoreactive CD8+ T cells were diabetogenic in nonobese diabetic (NOD) mice. High glucose intake upregulated pancreatic OTUB2 expression and amplified the OTUB258-66-specific CD8+ T-cell response in NOD mice. Repeated OTUB258-66 administration significantly reduced the incidence of T1D in NOD mice. Interestingly, peripheral blood mononuclear cells (PBMCs) from patients with T1D, but not from healthy controls, showed a positive IFN-γ response to human OTUB2 peptides. This study provides not only a new explanation for the role of ERS in promoting β-cell-targeted autoimmunity but also a potential target for the prevention and treatment of T1D. The data are available via ProteomeXchange with the identifier PXD041227.
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Affiliation(s)
- Lina Wang
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
- Key Laboratory of Immune Microenvironment and Inflammatory Disease Research in Universities of Shandong Province, School of Basic Medical Sciences, Shandong Second Medical University, Weifang, 261053, China
- Department of Immunology, Medical College of Qingdao University, Qingdao, 266071, China
| | - Shushu Yang
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Gaohui Zhu
- Department of Endocrinology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China
| | - Jie Li
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Gang Meng
- Department of Pathology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Xiaoling Chen
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Mengjun Zhang
- Department of Pharmaceutical Analysis, College of Pharmacy, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Shufeng Wang
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Xiangqian Li
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Yu Pan
- Department of Endocrinology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China
| | - Yi Huang
- National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Li Wang
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
| | - Yuzhang Wu
- Department of Immunology, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
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Yan YS, Feng C, Yu DQ, Tian S, Zhou Y, Huang YT, Cai YT, Chen J, Zhu MM, Jin M. Long-term outcomes and potential mechanisms of offspring exposed to intrauterine hyperglycemia. Front Nutr 2023; 10:1067282. [PMID: 37255932 PMCID: PMC10226394 DOI: 10.3389/fnut.2023.1067282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 04/06/2023] [Indexed: 06/01/2023] Open
Abstract
Diabetes mellitus during pregnancy, which can be classified into pregestational diabetes and gestational diabetes, has become much more prevalent worldwide. Maternal diabetes fosters an intrauterine abnormal environment for fetus, which not only influences pregnancy outcomes, but also leads to fetal anomaly and development of diseases in later life, such as metabolic and cardiovascular diseases, neuropsychiatric outcomes, reproduction malformation, and immune dysfunction. The underlying mechanisms are comprehensive and ambiguous, which mainly focus on microbiota, inflammation, reactive oxygen species, cell viability, and epigenetics. This review concluded with the influence of intrauterine hyperglycemia on fetal structure development and organ function on later life and outlined potential mechanisms that underpin the development of diseases in adulthood. Maternal diabetes leaves an effect that continues generations after generations through gametes, thus more attention should be paid to the prevention and treatment of diabetes to rescue the pathological attacks of maternal diabetes from the offspring.
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Affiliation(s)
- Yi-Shang Yan
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Chun Feng
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Dan-Qing Yu
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Shen Tian
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yin Zhou
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yi-Ting Huang
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yi-Ting Cai
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jian Chen
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
| | - Miao-Miao Zhu
- Department of Operating Theatre, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Min Jin
- Department of Reproductive Medicine, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, School of Medicine, Zhejiang University, Hangzhou, China
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3
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Jung S, Lee JS. Single-Cell Genomics for Investigating Pathogenesis of Inflammatory Diseases. Mol Cells 2023; 46:120-129. [PMID: 36859476 PMCID: PMC9982059 DOI: 10.14348/molcells.2023.0002] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 03/03/2023] Open
Abstract
Recent technical advances have enabled unbiased transcriptomic and epigenetic analysis of each cell, known as "single-cell analysis". Single-cell analysis has a variety of technical approaches to investigate the state of each cell, including mRNA levels (transcriptome), the immune repertoire (immune repertoire analysis), cell surface proteins (surface proteome analysis), chromatin accessibility (epigenome), and accordance with genome variants (eQTLs; expression quantitative trait loci). As an effective tool for investigating robust immune responses in coronavirus disease 2019 (COVID-19), many researchers performed single-cell analysis to capture the diverse, unbiased immune cell activation and differentiation. Despite challenges elucidating the complicated immune microenvironments of chronic inflammatory diseases using existing experimental methods, it is now possible to capture the simultaneous immune features of different cell types across inflamed tissues using various single-cell tools. In this review, we introduce patient-based and experimental mouse model research utilizing single-cell analyses in the field of chronic inflammatory diseases, as well as multi-organ atlas targeting immune cells.
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Affiliation(s)
- Seyoung Jung
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jeong Seok Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
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Ju Y, Janga SR, Klinngam W, MacKay JA, Hawley D, Zoukhri D, Edman MC, Hamm-Alvarez SF. NOD and NOR mice exhibit comparable development of lacrimal gland secretory dysfunction but NOD mice have more severe autoimmune dacryoadenitis. Exp Eye Res 2018; 176:243-251. [PMID: 30201519 PMCID: PMC6215720 DOI: 10.1016/j.exer.2018.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/03/2018] [Accepted: 09/04/2018] [Indexed: 12/16/2022]
Abstract
The male Non-Obese Diabetic (NOD) mouse is an established model of autoimmune dacryoadenitis characteristic of Sjögren's Syndrome (SS), but development of diabetes may complicate studies. The Non-Obese Diabetes Resistant (NOR) mouse is a MHC-II matched diabetes-resistant alternative, but development of autoimmune dacryoadenitis is not well-characterized. We compare features of SS in male NOD and NOR mice at 12 and 20 weeks. Stimulated tear secretion was decreased in 12 week NOD relative to BALB/c mice (p < 0.05), while by 20 weeks both NOD and NOR showed decreased stimulated tear secretion relative to BALB/c mice (p < 0.001). Tear CTSS activity was elevated in NOD and NOR relative to BALB/c mice (p < 0.05) at 12 and 20 weeks. While NOD and NOR lacrimal glands (LG) showed increased LG lymphocytic infiltration at 12 and 20 weeks relative to BALB/c mouse LG (p < 0.05), the percentage in NOD was higher relative to NOR at each age (p < 0.05). Gene expression of CTSS, MHC II and IFN-γ in LG were significantly increased in NOD but not NOR relative to BALB/c at 12 and 20 weeks. Redistribution of the secretory effector, Rab3D in acinar cells was observed at both time points in NOD and NOR, but thinning of myoepithelial cells at 12 weeks in NOD and NOR mice was restored by 20 weeks in NOR mice. NOD and NOR mice share features of SS-like autoimmune dacryoadenitis, suggesting common disease etiology. Other findings suggest more pronounced lymphocytic infiltration in NOD mouse LG including increased pro-inflammatory factors that may be unique to this model.
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Affiliation(s)
- Yaping Ju
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Srikanth Reddy Janga
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Wannita Klinngam
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - J Andrew MacKay
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Dillon Hawley
- Department of Comprehensive Care, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Driss Zoukhri
- Department of Comprehensive Care, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Maria C Edman
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Sarah F Hamm-Alvarez
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States; Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States.
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5
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De Riva A, Wållberg M, Ronchi F, Coulson R, Sage A, Thorne L, Goodfellow I, McCoy KD, Azuma M, Cooke A, Busch R. Regulation of type 1 diabetes development and B-cell activation in nonobese diabetic mice by early life exposure to a diabetogenic environment. PLoS One 2017; 12:e0181964. [PMID: 28771521 PMCID: PMC5542673 DOI: 10.1371/journal.pone.0181964] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 07/10/2017] [Indexed: 12/12/2022] Open
Abstract
Microbes, including viruses, influence type 1 diabetes (T1D) development, but many such influences remain undefined. Previous work on underlying immune mechanisms has focussed on cytokines and T cells. Here, we compared two nonobese diabetic (NOD) mouse colonies, NODlow and NODhigh, differing markedly in their cumulative T1D incidence (22% vs. 90% by 30 weeks in females). NODhigh mice harbored more complex intestinal microbiota, including several pathobionts; both colonies harbored segmented filamentous bacteria (SFB), thought to suppress T1D. Young NODhigh females had increased B-cell activation in their mesenteric lymph nodes. These phenotypes were transmissible. Co-housing of NODlow with NODhigh mice after weaning did not change T1D development, but T1D incidence was increased in female offspring of co-housed NODlow mice, which were exposed to the NODhigh environment both before and after weaning. These offspring also acquired microbiota and B-cell activation approaching those of NODhigh mice. In NODlow females, the low rate of T1D was unaffected by cyclophosphamide but increased by PD-L1 blockade. Thus, environmental exposures that are innocuous later in life may promote T1D progression if acquired early during immune development, possibly by altering B-cell activation and/or PD-L1 function. Moreover, T1D suppression in NOD mice by SFB may depend on the presence of other microbial influences. The complexity of microbial immune regulation revealed in this murine model may also be relevant to the environmental regulation of human T1D.
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Affiliation(s)
- Alessandra De Riva
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Maja Wållberg
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Francesca Ronchi
- Maurice Müller Laboratories (DKF), Universitätsklinik für Viszerale Chirurgie und Medizin Inselspital, University of Bern, Bern, Switzerland
| | - Richard Coulson
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Andrew Sage
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Lucy Thorne
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Ian Goodfellow
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Kathy D. McCoy
- Maurice Müller Laboratories (DKF), Universitätsklinik für Viszerale Chirurgie und Medizin Inselspital, University of Bern, Bern, Switzerland
| | - Miyuki Azuma
- Department of Molecular Immunology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan
| | - Anne Cooke
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Robert Busch
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
- Department of Life Sciences, University of Roehampton, London, United Kingdom
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6
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Prevosto C, Usmani MF, McDonald S, Gumienny AM, Key T, Goodman RS, Gaston JSH, Deery MJ, Busch R. Allele-Independent Turnover of Human Leukocyte Antigen (HLA) Class Ia Molecules. PLoS One 2016; 11:e0161011. [PMID: 27529174 PMCID: PMC4987023 DOI: 10.1371/journal.pone.0161011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 07/28/2016] [Indexed: 11/29/2022] Open
Abstract
Major histocompatibility complex class I (MHCI) glycoproteins present cytosolic peptides to CD8+ T cells and regulate NK cell activity. Their heavy chains (HC) are expressed from up to three MHC gene loci (human leukocyte antigen [HLA]-A, -B, and -C in humans), whose extensive polymorphism maps predominantly to the antigen-binding groove, diversifying the bound peptide repertoire. Codominant expression of MHCI alleles is thus functionally critical, but how it is regulated is not fully understood. Here, we have examined the effect of polymorphism on the turnover rates of MHCI molecules in cell lines with functional MHCI peptide loading pathways and in monocyte-derived dendritic cells (MoDCs). Proteins were labeled biosynthetically with heavy water (2H2O), folded MHCI molecules immunoprecipitated, and tryptic digests analysed by mass spectrometry. MHCI-derived peptides were assigned to specific alleles and isotypes, and turnover rates quantified by 2H incorporation, after correcting for cell growth. MHCI turnover half-lives ranged from undetectable to a few hours, depending on cell type, activation state, donor, and MHCI isotype. However, in all settings, the turnover half-lives of alleles of the same isotype were similar. Thus, MHCI protein turnover rates appear to be allele-independent in normal human cells. We propose that this is an important feature enabling the normal function and codominant expression of MHCI alleles.
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Affiliation(s)
- Claudia Prevosto
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - M. Farooq Usmani
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Sarah McDonald
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | | | - Tim Key
- Tissue Typing Laboratory, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Reyna S. Goodman
- Tissue Typing Laboratory, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - J. S. Hill Gaston
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Michael J. Deery
- Cambridge Centre for Proteomics, University of Cambridge, Cambridge, United Kingdom
| | - Robert Busch
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
- Department of Life Sciences, University of Roehampton, London, United Kingdom
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Bannard O, McGowan SJ, Ersching J, Ishido S, Victora GD, Shin JS, Cyster JG. Ubiquitin-mediated fluctuations in MHC class II facilitate efficient germinal center B cell responses. J Exp Med 2016; 213:993-1009. [PMID: 27162138 PMCID: PMC4886361 DOI: 10.1084/jem.20151682] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Accepted: 04/04/2016] [Indexed: 01/21/2023] Open
Abstract
Antibody affinity maturation occurs in germinal centers (GCs) through iterative rounds of somatic hypermutation and selection. Selection involves B cells competing for T cell help based on the amount of antigen they capture and present on their MHC class II (MHCII) proteins. How GC B cells are able to rapidly and repeatedly transition between mutating their B cell receptor genes and then being selected shortly after is not known. We report that MHCII surface levels and degradation are dynamically regulated in GC B cells. Through ectopic expression of a photoconvertible MHCII-mKikGR chimeric gene, we found that individual GC B cells differed in the rates of MHCII protein turnover. Fluctuations in surface MHCII levels were dependent on ubiquitination and the E3 ligase March1. Increases in March1 expression in centroblasts correlated with decreases in surface MHCII levels, whereas CD83 expression in centrocytes helped to stabilize MHCII at that stage. Defects in MHCII ubiquitination caused GC B cells to accumulate greater amounts of a specific peptide-MHCII (pMHCII), suggesting that MHCII turnover facilitates the replacement of old complexes. We propose that pMHCII complexes are periodically targeted for degradation in centroblasts to favor the presentation of recently acquired antigens, thereby promoting the fidelity and efficiency of selection.
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Affiliation(s)
- Oliver Bannard
- Medical Research Council Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, OX3 9DS Oxford, England, UK Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143 Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
| | - Simon J McGowan
- Computational Biology Research Group, Weatherall Institute of Molecular Medicine, University of Oxford, OX3 9DS Oxford, England, UK
| | - Jonatan Ersching
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142
| | - Satoshi Ishido
- Laboratory of Integrative Infection Immunity, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | | | - Jeoung-Sook Shin
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
| | - Jason G Cyster
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143 Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
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Abstract
The non-obese diabetic (NOD) mouse is a polygenic model for type 1 diabetes that is characterized by insulitis, a leukocytic infiltration of the pancreatic islets. During ~35 years since the original inbred strain was developed in Japan, NOD substrains have been established at different laboratories around the world. Although environmental differences among NOD colonies capable of impacting diabetes incidence have been recognized, differences arising from genetic divergence have not been analyzed previously. We use both mouse diversity array and whole-exome capture sequencing platforms to identify genetic differences distinguishing five NOD substrains. We describe 64 single-nucleotide polymorphisms, and two short indels that differ in coding regions of the five NOD substrains. A 100-kb deletion on Chromosome 3 distinguishes NOD/ShiLtJ and NOD/ShiLtDvs from three other substrains, whereas a 111-kb deletion in the Icam2 gene on Chromosome 11 is unique to the NOD/ShiLtDvs genome. The extent of genetic divergence for NOD substrains is compared with similar studies for C57BL6 and BALB/c substrains. As mutations are fixed to homozygosity by continued inbreeding, significant differences in substrain phenotypes are to be expected. These results emphasize the importance of using embryo freezing methods to minimize genetic drift within substrains and of applying appropriate genetic nomenclature to permit substrain recognition when one is used.
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9
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De Riva A, Busch R. MHC Class II Protein Turnover In vivo and Its Relevance for Autoimmunity in Non-Obese Diabetic Mice. Front Immunol 2013; 4:399. [PMID: 24324466 PMCID: PMC3839011 DOI: 10.3389/fimmu.2013.00399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 11/08/2013] [Indexed: 11/19/2022] Open
Abstract
Major histocompatibility complex class II (MHCII) proteins are loaded with endosomal peptides and reside at the surface of antigen-presenting cells (APCs) for a time before being degraded. In vitro, MHCII protein levels and turnover are affected by peptide loading and by rates of ubiquitin-dependent internalization from the cell surface, which is in turn affected by APC type and activation state. Prior work suggested that fast turnover of disease-associated MHCII alleles may contribute to autoimmunity. We recently developed novel stable isotope tracer techniques to test this hypothesis in vivo. In non-obese diabetic (NOD) mice, a model of type 1 diabetes (T1D), MHCII turnover was affected by APC type, but unaffected by disease-associated structural polymorphism. Differences in MHCII turnover were observed between NOD colonies with high and low T1D incidence, but fast turnover was dispensable for autoimmunity. Moreover, NOD mice with gene knockouts of peptide loading cofactors do not develop T1D. Thus, fast turnover does not appear pathogenic, and conventional antigen presentation is critical for autoimmunity in NOD mice. However, shared environmental factors may underpin colony differences in MHCII protein turnover, immune regulation, and pathogenesis.
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Affiliation(s)
| | - Robert Busch
- Department of Medicine, University of Cambridge, Cambridge, UK
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