scholarly journals Autoimmunity to hypocretin and molecular mimicry to flu antigens in Type 1 narcolepsy

2018 ◽  
Author(s):  
Guo Luo ◽  
Aditya Ambati ◽  
Ling Lin ◽  
Mélodie Bonvalet ◽  
Markku Partinen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Influenza A ◽  
Molecular Mimicry ◽  
Neuronal Loss ◽  
Human Leukocyte ◽  
Cell Receptor ◽  
Blood Monocytes ◽  
Genetic Components

AbstractType 1 narcolepsy (T1N) is caused by hypocretin (HCRT) neuronal loss. Association with the Human Leukocyte Antigen (HLA)-DQB1*06:02/DQA1*01:02 (98% vs 25%) heterodimer (DQ0602), T cell receptor (TCR) and other immune loci suggest autoimmunity but autoantigen(s) are unknown. Onset is seasonal and associated with influenza A, notably pandemic 2009 H1N1 (pH1N1). An extensive unbiased DQ0602 binding peptide screen was performed encompassing peptides derived from Pandemrix® X-179-A pH1N1 influenza-A vaccine, a known T1N trigger, other H1N1 strains, and potential human autoantigens HCRT and RFX4, identifying 109 binders. The presence of cognate tetramer-peptide specific CD4+ T cells was studied in 35 narcolepsy cases and 22 DQ0602 controls after expansion of antigen-specific cells in Peripheral Blood Monocytes Cell (PBMC) cultures. Higher reactivity to influenza epitopes pHA273-287 (pH1N1 specific) and PR8 (H1N1 pre 2009)-specific NP17-31 were observed in T1N. Extensive reactivity to C-amidated but not native version of HCRT54-66 and HCRT86-97, which are two highly homologous peptides (HCRTNH2) was observed with higher frequencies of specific T cells in T1N. TCRα/β CDR3 sequences found in pHA273-287, NP17-31 and HCRTNH2 tetramer positive CD4+ cells were also retrieved in single INFγ-secreting CD4+ sorted cells stimulated with Pandemrix®, confirming immunodominance and functional significance in DQ0602-mediated responses and molecular mimicry. TCRα/β CDR3 motifs of HCRT54-66 and HCRT86-97 tetramers were extensively shared. Particularly notable was sharing across subjects of an CDR3α, CAVETDSWGKLQF (in association with various CDR3β that used TRAJ24, a chain modulated by Single Nucleotide Polymorphism (SNPs) rs1154155 and rs1483979 associated with T1N. Sharing of CDR3β CASSQETQGRNYGYTF (in association with various CDR3α was also observed with HCRTNH2 and pHA273-287-tetramers across subjects. This segment uses TRBV4-2, a segment modulated by narcolepsy-associated SNP rs1008599. Higher HCRTNH2 positive CD4+ T cell numbers in T1N together with sharing of J24 CAVETDSWGKLQF in HCRTNH2 autoimmune responses, indicates causal DQ0602-mediated CD4+ autoreactivity to HCRT in T1N. Our results provide evidence for autoimmunity and molecular mimicry with flu antigens modulated by genetic components in the pathophysiology of T1N.

scholarly journals Autoimmunity to hypocretin and molecular mimicry to flu in type 1 narcolepsy

2018 ◽  
Vol 115 (52) ◽  
pp. E12323-E12332 ◽  
Author(s):  
Guo Luo ◽  
Aditya Ambati ◽  
Ling Lin ◽  
Mélodie Bonvalet ◽  
Markku Partinen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell Receptors ◽  
Influenza A ◽  
Molecular Mimicry ◽  
Neuronal Loss ◽  
Genetic Components ◽  
2009 H1n1 ◽  
A Chain ◽  
Immune Loci

Type 1 narcolepsy (T1N) is caused by hypocretin/orexin (HCRT) neuronal loss. Association with the HLA DQB1*06:02/DQA1*01:02 (98% vs. 25%) heterodimer (DQ0602), T cell receptors (TCR) and other immune loci suggest autoimmunity but autoantigens are unknown. Onset is seasonal and associated with influenza A, notably pandemic 2009 H1N1 (pH1N1) infection and vaccination (Pandemrix). Peptides derived from HCRT and influenza A, including pH1N1, were screened for DQ0602 binding and presence of cognate DQ0602 tetramer-peptide–specific CD4+ T cells tested in 35 T1N cases and 22 DQ0602 controls. Higher reactivity to influenza pHA273–287 (pH1N1 specific), PR8 (H1N1 pre-2009 and H2N2)-specific NP17–31 and C-amidated but not native version of HCRT54–66 and HCRT86–97 (HCRTNH2) were observed in T1N. Single-cell TCR sequencing revealed sharing of CDR3β TRBV4-2-CASSQETQGRNYGYTF in HCRTNH2 and pHA273–287-tetramers, suggesting molecular mimicry. This public CDR3β uses TRBV4-2, a segment modulated by T1N-associated SNP rs1008599, suggesting causality. TCR-α/β CDR3 motifs of HCRT54–66-NH2 and HCRT86–97-NH2 tetramers were extensively shared: notably public CDR3α, TRAV2-CAVETDSWGKLQF-TRAJ24, that uses TRAJ24, a chain modulated by T1N-associated SNPs rs1154155 and rs1483979. TCR-α/β CDR3 sequences found in pHA273–287, NP17–31, and HCRTNH2 tetramer-positive CD4+ cells were also retrieved in single INF-γ–secreting CD4+ sorted cells stimulated with Pandemrix, independently confirming these results. Our results provide evidence for autoimmunity and molecular mimicry with flu antigens modulated by genetic components in the pathophysiology of T1N.

scholarly journals Heightened self-reactivity associated with selective survival, but not expansion, of naïve virus-specific CD8+ T cells in aged mice

2016 ◽  
Vol 113 (5) ◽  
pp. 1333-1338 ◽  
Author(s):  
Kylie M. Quinn ◽  
Sophie G. Zaloumis ◽  
Tania Cukalac ◽  
Wan-Ting Kan ◽  
Xavier Y. X. Sng ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Influenza A ◽  
Cytotoxic T Lymphocyte ◽  
Clonal Diversity ◽  
Cell Receptor ◽  
Advanced Age ◽  
Age Related ◽  
Self Recognition ◽  
Underlying Mechanisms

In advanced age, decreased CD8+ cytotoxic T-lymphocyte (CTL) responses to novel pathogens and cancer is paralleled by a decline in the number and function of naïve CTL precursors (CTLp). Although the age-related fall in CD8+ T-cell numbers is well established, neither the underlying mechanisms nor the extent of variation for different epitope specificities have been defined. Furthermore, naïve CD8+ T cells expressing high levels of CD44 accumulate with age, but it is unknown whether this accumulation reflects their preferential survival or an age-dependent driver of CD8+ T-cell proliferation. Here, we track the number and phenotype of four influenza A virus (IAV)-specific CTLp populations in naïve C57BL/6 (B6) mice during aging, and compare T-cell receptor (TCR) clonal diversity for the CD44hi and CD44lo subsets of one such population. We show differential onset of decline for several IAV-specific CD8+ T-cell populations with advanced age that parallel age-associated changes in the B6 immunodominance hierarchy, suggestive of distinct impacts of aging on different epitope-specific populations. Despite finding no evidence of clonal expansions in an aged, epitope-specific TCR repertoire, nonrandom alterations in TCR usage were observed, along with elevated CD5 and CD8 coreceptor expression. Collectively, these data demonstrate that naïve CD8+ T cells expressing markers of heightened self-recognition are selectively retained, but not clonally expanded, during aging.

scholarly journals In Vivo Selection of T-Cell Receptor Junctional Region Sequences by HLA-A2 Human T-Cell Lymphotropic Virus Type 1 Tax11-19 Peptide Complexes

2001 ◽  
Vol 75 (2) ◽  
pp. 1065-1071 ◽  
Author(s):  
Mineki Saito ◽  
Graham P. Taylor ◽  
Akiko Saito ◽  
Yoshitaka Furukawa ◽  
Koichiro Usuku ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Virus Type ◽  
Cell Receptor ◽  
Antigen Specificity ◽  
Human T Cell ◽  
Cdr3 Region

ABSTRACT Using HLA-peptide tetrameric complexes, we isolated human T-cell lymphotrophic virus type 1 Tax peptide-specific CD8+ T cells ex vivo. Antigen-specific amino acid motifs were identified in the T-cell receptor Vβ CDR3 region of clonally expanded CD8+ T cells. This result directly confirms the importance of the CDR3 region in determining the antigen specificity in vivo.

scholarly journals Recent advances in T-cell engineering for use in immunotherapy

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 2344 ◽  
Author(s):  
Preeti Sharma ◽  
David M. Kranz
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Complex Molecule ◽  
Major Histocompatibility Complex Molecule ◽  
Human Leukocyte ◽  
Cell Receptor ◽  
Single Chain ◽  
Cell Therapies ◽  
Recent Advances

Adoptive T-cell therapies have shown exceptional promise in the treatment of cancer, especially B-cell malignancies. Two distinct strategies have been used to redirect the activity of ex vivo engineered T cells. In one case, the well-known ability of the T-cell receptor (TCR) to recognize a specific peptide bound to a major histocompatibility complex molecule has been exploited by introducing a TCR against a cancer-associated peptide/human leukocyte antigen complex. In the other strategy, synthetic constructs called chimeric antigen receptors (CARs) that contain antibody variable domains (single-chain fragments variable) and signaling domains have been introduced into T cells. Whereas many reviews have described these two approaches, this review focuses on a few recent advances of significant interest. The early success of CARs has been followed by questions about optimal configurations of these synthetic constructs, especially for efficacy against solid tumors. Among the many features that are important, the dimensions and stoichiometries of CAR/antigen complexes at the synapse have recently begun to be appreciated. In TCR-mediated approaches, recent evidence that mutated peptides (neoantigens) serve as targets for endogenous T-cell responses suggests that these neoantigens may also provide new opportunities for adoptive T-cell therapies with TCRs.

scholarly journals Proinsulin-Reactive CD4 T Cells in the Islets of Type 1 Diabetes Organ Donors

2021 ◽  
Vol 12 ◽  
Author(s):  
Laurie G. Landry ◽  
Amanda M. Anderson ◽  
Holger A. Russ ◽  
Liping Yu ◽  
Sally C. Kent ◽  
...  
Keyword(s):  
T Cells ◽  
Type 1 Diabetes ◽  
T Cell ◽  
Cd4 T Cells ◽  
Pancreatic Beta Cells ◽  
Hot Spot ◽  
Cell Receptor ◽  
Organ Donors ◽  
Hla Dq

Proinsulin is an abundant protein that is selectively expressed by pancreatic beta cells and has been a focus for development of antigen-specific immunotherapies for type 1 diabetes (T1D). In this study, we sought to comprehensively evaluate reactivity to preproinsulin by CD4 T cells originally isolated from pancreatic islets of organ donors having T1D. We analyzed 187 T cell receptor (TCR) clonotypes expressed by CD4 T cells obtained from six T1D donors and determined their response to 99 truncated preproinsulin peptide pools, in the presence of autologous B cells. We identified 14 TCR clonotypes from four out of the six donors that responded to preproinsulin peptides. Epitopes were found across all of proinsulin (insulin B-chain, C-peptide, and A-chain) including four hot spot regions containing peptides commonly targeted by TCR clonotypes derived from multiple T1D donors. Of importance, these hot spots overlap with peptide regions to which CD4 T cell responses have previously been detected in the peripheral blood of T1D patients. The 14 TCR clonotypes recognized proinsulin peptides presented by various HLA class II molecules, but there was a trend for dominant restriction with HLA-DQ, especially T1D risk alleles DQ8, DQ2, and DQ8-trans. The characteristics of the tri-molecular complex including proinsulin peptide, HLA-DQ molecule, and TCR derived from CD4 T cells in islets, provides an essential basis for developing antigen-specific biomarkers as well as immunotherapies.

scholarly journals Self-reactive human CD4 T cell clones form unusual immunological synapses

2012 ◽  
Vol 209 (2) ◽  
pp. 335-352 ◽  
Author(s):  
David A. Schubert ◽  
Susana Gordo ◽  
Joseph J. Sabatino ◽  
Santosh Vardhana ◽  
Etienne Gagnon ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Receptor ◽  
Tcr Signaling ◽  
T Cell Clones ◽  
Cell Clones ◽  
Immunological Synapses ◽  
High Degree ◽  
Self Antigen

Recognition of self–peptide-MHC (pMHC) complexes by CD4 T cells plays an important role in the pathogenesis of many autoimmune diseases. We analyzed formation of immunological synapses (IS) in self-reactive T cell clones from patients with multiple sclerosis and type 1 diabetes. All self-reactive T cells contained a large number of phosphorylated T cell receptor (TCR) microclusters, indicative of active TCR signaling. However, they showed little or no visible pMHC accumulation or transport of TCR–pMHC complexes into a central supramolecular activation cluster (cSMAC). In contrast, influenza-specific T cells accumulated large quantities of pMHC complexes in microclusters and a cSMAC, even when presented with 100-fold lower pMHC densities. The self-reactive T cells also maintained a high degree of motility, again in sharp contrast to virus-specific T cells. 2D affinity measurements of three of these self-reactive T cell clones demonstrated a normal off-rate but a slow on-rate of TCR binding to pMHC. These unusual IS features may facilitate escape from negative selection by self-reactive T cells encountering very small amounts of self-antigen in the thymus. However, these same features may enable acquisition of effector functions by self-reactive T cells encountering large amounts of self-antigen in the target organ of the autoimmune disease.

scholarly journals T-cell-receptor signalling in inositol 1,4,5-trisphosphate receptor (IP3R) type-1-deficient mice: is IP3R type 1 essential for T-cell-receptor signalling?

1998 ◽  
Vol 333 (3) ◽  
pp. 615-619 ◽  
Author(s):  
Junji HIROTA ◽  
Masashi BABA ◽  
Mineo MATSUMOTO ◽  
Teiichi FURUICHI ◽  
Kiyoshi TAKATSU ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Line ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
Cell Phenotype ◽  
Receptor Signalling ◽  
Inositol 1,4,5 Trisphosphate ◽  
Trisphosphate Receptor

Stimulation of T-cells via the T-cell receptor (TCR) complex is accompanied by an increase in intracellular Ca2+ concentration ([Ca2+]i). Recently, it was reported that a stable transformant of the human T-cell line, Jurkat, expressing an antisense cDNA construct of inositol 1,4,5-trisphosphate receptor (IP3R) type 1 (IP3R1), failed to demonstrate increased [Ca2+]i or interleukin-2 production after TCR stimulation and was also resistant to apoptotic stimuli. This cell line lacked IP3R1 expression, but expressed the type-2 and -3 receptors, IP3R2 and IP3R3 respectively [Jayaraman, Ondriasova, Ondrias, Harnick and Marks (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 6007–6011, and Jayaraman and Marks (1997) Mol. Cell. Biol. 17, 3005–3012]. The authors concluded that IP3R1 is essential for TCR signalling and suggested that Ca2+ release via IP3R1 is a critical mediator of apoptosis. To establish whether a loss of IP3R1 function in T-cells occurred in vivo and in vitro, we investigated Ca2+ signalling after TCR stimulation and the properties of T-cells using IP3R1-deficient (IP3R1-/-) mice. As IP3R1-/- mice die at weaning, we transplanted bone marrow cells of IP3R1-/- mice into irradiated wild-type mice. Western blot analysis showed that the recipient IP3R1-containing (IP3R1+/+) lymphocytes were replaced by the donor IP3R1-/- lymphocytes after transplantation and that expression of IP3R2 and IP3R3 was unaltered. In contrast with the previous reports, T-cells lacking IP3R1 were able to mobilize Ca2+ from intracellular Ca2+ stores after stimulation via the TCR. We observed no significant differences between IP3R1+/+ and IP3R1-/- T-cells in terms of the number of thymocytes and splenocytes, the proportion of the T-cell phenotype, proliferative response to anti-CD3 monoclonal antibody (mAb) stimulation and cell viability. Therefore IP3R1 is not essential for T-cell development and function.

scholarly journals Unique Clinical and Pathological Features in HLA-DRB1*0401–restricted MBP 111–129–specific Humanized TCR Transgenic Mice

2004 ◽  
Vol 200 (2) ◽  
pp. 223-234 ◽  
Author(s):  
Jacqueline A. Quandt ◽  
Mirza Baig ◽  
Karen Yao ◽  
Kazuyuki Kawamura ◽  
Jaebong Huh ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cranial Nerve ◽  
Cell Clone ◽  
Human Leukocyte ◽  
Cell Receptor ◽  
Nerve Roots ◽  
Pathogenic Potential ◽  
Abnormal Gait ◽  
T Cell Clone

Amino acid residues 111–129 represent an immunodominant epitope of myelin basic protein (MBP) in humans with human leukocyte antigen (HLA)-DRB1*0401 allele(s). The MBP 111–129–specific T cell clone MS2-3C8 was repeatedly isolated from a patient with multiple sclerosis (MS), suggesting an involvement of MS2-3C8 T cells in the pathogenesis. To address the pathogenic potential of the MS2-3C8 T cell clone, we generated transgenic (Tg) mice expressing its T cell receptor and restriction element, HLA-DRB1*0401, to examine the pathogenic characteristics of MS2-3C8 Tg T cells by adoptive transfer into HLA-DRB1*0401 Tg mice. In addition to the ascending paralysis typical of experimental autoimmune encephalomyelitis, mice displayed dysphagia due to restriction in jaw and tongue movements and abnormal gait. In accordance with the clinical phenotype, infiltrates of MS2-3C8 Tg T cells and inflammatory lesions were predominantly located in the brainstem and the cranial nerve roots in addition to the spinal cord and spinal nerve roots. Together, these data suggest a pathogenic role of MBP-specific T cells in inflammatory demyelination within the brainstem and cranial nerve roots during the progression of MS. This notion may help to explain the clinical and pathological heterogeneity of MS.

scholarly journals Targeting transcriptional coregulator OCA-B/Pou2af1 blocks activated autoreactive T cells in the pancreas and type-1 diabetes

2020 ◽  
Author(s):  
Heejoo Kim ◽  
Jelena Perovanovic ◽  
Arvind Shakya ◽  
Zuolian Shen ◽  
Cody N. German ◽  
...  
Keyword(s):  
T Cells ◽  
Type 1 Diabetes ◽  
T Cell ◽  
Target Genes ◽  
Autoimmune Diabetes ◽  
Nod Mice ◽  
Cell Receptor ◽  
Glucose Levels ◽  
Transcriptional Coregulator

AbstractThe transcriptional coregulator OCA-B promotes expression of T cell target genes in cases of repeated antigen exposure, a necessary feature of autoimmunity. We hypothesized that T cell-specific OCA-B deletion and pharmacologic OCA-B inhibition would protect mice from autoimmune diabetes. We developed an Ocab conditional allele and backcrossed it onto a diabetes-prone NOD/ShiLtJ strain background. T cell-specific OCA-B loss protected mice from spontaneous disease. Protection was associated with large reductions in islet CD8+ T cell receptor specificities associated with diabetes pathogenesis. CD4+ clones associated with diabetes were present, but associated with anergic phenotypes. The protective effect of OCA-B loss was recapitulated using autoantigen-specific NY8.3 mice, but diminished in monoclonal models specific to artificial or neoantigens. Rationally-designed membrane-penetrating OCA-B peptide inhibitors normalized glucose levels, and reduced T cell infiltration and proinflammatory cytokine expression in newly-diabetic NOD mice. Together, the results indicate that OCA-B is a potent autoimmune regulator and a promising target for pharmacologic inhibition.~40-word summary statement for the online JEM table of contents and alertsKim and colleagues show that OCA-B in T cells is essential for the generation of type-1 diabetes. OCA-B loss leaves the pancreatic lymph nodes largely undisturbed, but associates autoreactive CD4+ T cells in the pancreas with anergy while deleting potentially autoreactive CD8+ T cells.SummaryKim et al. show that loss or inhibition of OCA-B in T cells protects mice from type-1 diabetes.

scholarly journals Inhibition of T-Cell Receptor Signal Transduction and Viral Expression by the Linker for Activation of T Cells-Interacting p12I Protein of Human T-Cell Leukemia/Lymphoma Virus Type 1

2007 ◽  
Vol 81 (17) ◽  
pp. 9088-9099 ◽  
Author(s):  
Risaku Fukumoto ◽  
Miroslav Dundr ◽  
Christophe Nicot ◽  
Anthony Adams ◽  
Valerio W. Valeri ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Virus Type ◽  
Calcium Release ◽  
Cell Receptor ◽  
Cell Leukemia ◽  
Viral Expression ◽  
Human T Cell

ABSTRACT The p12I protein of human T-cell leukemia/lymphoma virus type 1 (HTLV-1) is a small oncoprotein that increases calcium release following protein kinase C activation by phorbol myristate acetate, and importantly, this effect is linker for activation of T cells (LAT) independent. Here, we demonstrate that p12I inhibits the phosphorylation of LAT, Vav, and phospholipase C-γ1 and decreases NFAT (nuclear factor of activated T cells) activation upon engagement of the T-cell receptor (TCR) with anti-CD3 antibody. Furthermore, we demonstrate that p12I localizes to membrane lipid rafts and, upon engagement of the TCR, relocalizes to the interface between T cells and antigen-presenting cells, defined as the immunological synapse. A p12I knockout molecular clone of HTLV-1 expresses more virus upon antigen stimulation than the isogenic wild type, suggesting that, by decreasing T-cell responsiveness, p12I curtails viral expression. Thus, p12I has contrasting effects on TCR signaling: it down-regulates TCR in a LAT-dependent manner on one hand, and on the other, it increases calcium release in a LAT-independent manner. The negative regulation of T-cell activation by p12I may have evolved to minimize immune recognition of infected CD4+ T cells, to impair the function of infected cytotoxic CD8+ T cells, and to favor viral persistence in the infected host.

Sign in / Sign up

Export Citation Format

Share Document