scholarly journals CD8 T cell-mediated killing of orexinergic neurons induces a narcolepsy-like phenotype in mice

2016 ◽  
Vol 113 (39) ◽  
pp. 10956-10961 ◽  
Author(s):  
Raphaël Bernard-Valnet ◽  
Lidia Yshii ◽  
Clémence Quériault ◽  
Xuan-Hung Nguyen ◽  
Sébastien Arthaud ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Clinical Manifestations ◽  
Neuronal Loss ◽  
Human Leukocyte ◽  
T Cell Infiltration ◽  
Cytolytic Granule ◽  
Tight Association ◽  
Genetic And Environmental Factors ◽  
Self Antigen

Narcolepsy with cataplexy is a rare and severe sleep disorder caused by the destruction of orexinergic neurons in the lateral hypothalamus. The genetic and environmental factors associated with narcolepsy, together with serologic data, collectively point to an autoimmune origin. The current animal models of narcolepsy, based on either disruption of the orexinergic neurotransmission or neurons, do not allow study of the potential autoimmune etiology. Here, we sought to generate a mouse model that allows deciphering of the immune mechanisms leading to orexin+ neuron loss and narcolepsy development. We generated mice expressing the hemagglutinin (HA) as a “neo-self-antigen” specifically in hypothalamic orexin+ neurons (called Orex-HA), which were transferred with effector neo-self-antigen–specific T cells to assess whether an autoimmune process could be at play in narcolepsy. Given the tight association of narcolepsy with the human leukocyte antigen (HLA) HLA-DQB1*06:02 allele, we first tested the pathogenic contribution of CD4 Th1 cells. Although these T cells readily infiltrated the hypothalamus and triggered local inflammation, they did not elicit the loss of orexin+ neurons or clinical manifestations of narcolepsy. In contrast, the transfer of cytotoxic CD8 T cells (CTLs) led to both T-cell infiltration and specific destruction of orexin+ neurons. This phenotype was further aggravated upon repeated injections of CTLs. In situ, CTLs interacted directly with MHC class I-expressing orexin+ neurons, resulting in cytolytic granule polarization toward neurons. Finally, drastic neuronal loss caused manifestations mimicking human narcolepsy, such as cataplexy and sleep attacks. This work demonstrates the potential role of CTLs as final effectors of the immunopathological process in narcolepsy.

scholarly journals Regulation of the immune tolerance system determines the susceptibility to HLA-mediated abacavir-induced skin toxicity

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Takeshi Susukida ◽  
Saki Kuwahara ◽  
Binbin Song ◽  
Akira Kazaoka ◽  
Shigeki Aoki ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Tolerance ◽  
Human Leukocyte ◽  
Skin Toxicity ◽  
Effector Memory ◽  
T Cell Infiltration ◽  
Cytolytic Granule ◽  
Life Threatening ◽  
Programmed Death 1

AbstractIdiosyncratic drug toxicity (IDT) associated with specific human leukocyte antigen (HLA) allotype is a rare and unpredictable life-threatening adverse drug reaction for which prospective mechanistic studies in humans are difficult. Here, we show the importance of immune tolerance for IDT onset and determine whether it is susceptible to a common IDT, HLA-B*57:01-mediated abacavir (ABC)-induced hypersensitivity (AHS), using CD4+ T cell-depleted programmed death-1 receptor (PD-1)-deficient HLA-B*57:01 transgenic mice (B*57:01-Tg/PD-1−/−). Although AHS is not observed in B*57:01-Tg mice, ABC treatment increases the proportion of cytokine- and cytolytic granule-secreting effector memory CD8+ T cells in CD4+ T cell-depleted B*57:01-Tg/PD-1−/− mice, thereby inducing skin toxicity with CD8+ T cell infiltration, mimicking AHS. Our results demonstrate that individual differences in the immune tolerance system, including PD-1highCD8+ T cells and regulatory CD4+ T cells, may affect the susceptibility of humans to HLA-mediated IDT in humans.

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 AB0345 Th9 CELLS AND THEIR ASSOCIATED CYTOKINES: THE PROBABLE PLAYERS IN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) AND TYPE 1 DIABETES MELLITUS (T1DM)

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1197.2-1198
Author(s):  
N. Mohannad ◽  
M. Moaaz ◽  
R. Mohamed Shehata
Keyword(s):  
T Cells ◽  
T Cell ◽  
Disease Activity ◽  
Clinical Manifestations ◽  
Moderate Activity ◽  
Healthy Controls ◽  
Group I ◽  
Pancreatic Islets Of Langerhans ◽  
Th9 Cells ◽  
Significant Difference

Background:SLE is an autoimmune disease (AID) of unknown origin. Several factors can contribute to immune dysfunction in SLE.Interleukin 9 (IL9) is a newly emerging T cell-derived factor preferentially expressed by CD4+T cells: T helper 9 (Th9)IL9 targets different cell lineages, and can contribute to the development of allergic & AIDsWhether abnormal expression and secretion of IL9 are present in SLE patients (pts) still unidentified. It is also unclear whether IL9 exerts main proinflammatory or anti-inflammatory activities in SLE. T1DM is characterized by inflammation of the pancreatic islets of Langerhans. Insulitis progresses over time and β cells become destroyed then clinical DM is established. T1DM is regarded as a T cell-driven AIDObjectives:Evaluation of the expression of CD4+ IL9+ T cells & the level of IL9 in SLE pts compared to both healthy subjects & pts with another AID: T1DM.Also, to evaluate the correlation of these expressions with clinical features, laboratory parameters and SLE activityMethods:The study included: Group I 25 SLE pts fulfilling SLICC classification criteria divided into 2 subgroups (gps) according to SLE disease activity index (SLEDAI) IA: 20 pts with mild to moderate activity (<12) IB:5 pts with severe activity (>12) recruited from rheumatology clinic or internal medicine ward (Rheumatology unit), Main University Hospital, Alexandria. Group II 15 healthy individuals as a first control gp. Group III 15 pts with T1DM fulfilling the American Diabetes Association criteria as a second control gp. All pts were subjected to history taking, clinical examination,laboratory investigations: CBC,LFT,KFT,ESR,CRP,ANA,Anti-dsDNA,Th9 cell expression detection by flowcytometry and serum IL9 by ELISAResults:There was no statistical difference between all gps as regards age & sex but a significant increased ESR in SLE compared to controls & T1DM p< 0.001 p=0.001Th9 expression was highly increased in SLE pts, range 0.13-4.54% & mean ±SD=1.50 ± 1.47% than both control gps. In healthy controls Th9 ranged between 0.0-1.29% with mean 0.37 ±0.52%, while in T1DM pts ranged between 0.03 to 2.13% with mean of 0.67 ± 0.59%. A high significant difference was found between SLE pts and controls p=0.001, an insignificant rise was seen in SLE pts compared to T1DM pts p=0.157. A high significant increase in Th9 was found in severe SLE: mean of 3.74 ±1.15% than in pts with mild to moderate SLE: mean 0.94±0.88% p=<0.001IL9 level was highly increased in SLE pts: mean of 42.83± 23.98 pg/ml than both control gps. In healthy controls the mean was 8.54±13.27, while in T1DM with mean of 29.17±16.09 pg/ml. A high significant difference was found between SLE pts and normal controls p<0.001 but an insignificant rise with T1DM p=0.294. A high significant increase in IL9 in pts with severe ds compared to mild to moderate pts p<0.001.A significant direct correlation between Th9 & IL9 and SLEDAI/105 A significant direct correlation between damage index and Th9 p=0.040 but not IL9 p=0.053In SLE no significant relation between Th9 or IL9 & clinical manifestations or disease duration. A direct correlations between Th9 & ESR p=0.046 and CRP p=0.025,a significant correlation between IL9 and CRP p=0.033, no correlations between Th9&IL9 level and anti-dsDNA p=0.593& 0.4 Significant direct correlation between Th9 and IL9 in T1DM pts, still no correlation with glycemic profile. IL9 levels were significantly increased in SLE with elevated CRP p=0.033 & the % of Th9 cells were increased with elevated ESR and CRP p=0.025, 0.046Conclusion:In SLE pts; IL9 level and Th9 cells expression were significantly elevated compared to healthy controls. IL9 levels and the percentages of Th9 directly correlated with the SLE disease activity. IL9 levels also were significantly increased in T1DM pts compared to controls,but they were less expressed than in SLE. This suggests an important role of IL9 in the pathogenesis AIDs as SLEReferences:[1]Tahernia L et al. Cytokines in SLE: their role in pathogenesis of disease and possible therapeutic opportunities. Rheum Res 2017Disclosure of Interests:None declared

scholarly journals Decreased inflammatory cytokine production of antigen-specific CD4+ T cells in NMDA receptor encephalitis

2021 ◽  
Author(s):  
Le-Minh Dao ◽  
Marie-Luise Machule ◽  
Petra Bacher ◽  
Julius Hoffmann ◽  
Lam-Thanh Ly ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Autoimmune Encephalitis ◽  
Active Immunization ◽  
Inflammatory Cytokine Production ◽  
T Cell Infiltration ◽  
Nmda Receptor Encephalitis ◽  
Nmdar Encephalitis ◽  
Disease Specific

AbstractAnti-N-methyl-D-aspartate-receptor (NMDAR) encephalitis is the most common autoimmune encephalitis with psychosis, amnesia, seizures and dyskinesias. The disease is mediated by pathogenic autoantibodies against the NR1 subunit that disrupt NMDAR function. Antibody infusion into mouse brains can recapitulate encephalitis symptoms, while active immunization resulted also in strong T cell infiltration into the hippocampus. However, whether T cells react against NMDAR and their specific contribution to disease development are poorly understood. Here we characterized the ex vivo frequency and phenotype of circulating CD4+ T helper (TH) cells reactive to NR1 protein using antigen-reactive T cell enrichment (ARTE) in 24 patients with NMDAR encephalitis, 13 patients with LGI1 encephalitis and 51 matched controls. Unexpectedly, patients with NMDAR encephalitis had lower frequencies of CD154-expressing NR1-reactive TH cells than healthy controls and produced significantly less inflammatory cytokines. No difference was seen in T cells reactive to the synaptic target LGI1 (Leucine-rich glioma-inactivated 1), ubiquitous Candida antigens or neoantigens, suggesting that the findings are disease-specific and not related to therapeutic immunosuppression. Also, patients with LGI1 encephalitis showed unaltered numbers of LGI1 antigen-reactive T cells. The data reveal disease-specific functional alterations of circulating NMDAR-reactive TH cells in patients with NMDAR encephalitis and challenge the idea that increased pro-inflammatory NMDAR-reactive T cells contribute to disease pathogenesis.

scholarly journals 49 In situ phenotypic analysis of T cells in the tumor microenvironment of a pre-clinical model of non-small cell lung cancer (NSCLC) by tissue sectioning and whole-mount immunofluorescence imaging

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A52-A52
Author(s):  
Elen Torres ◽  
Stefani Spranger
Keyword(s):  
T Cells ◽  
Spatial Distribution ◽  
T Cell ◽  
Spatial Location ◽  
Cell Infiltration ◽  
Cell Populations ◽  
Tumor Bearing ◽  
T Cell Infiltration ◽  
Volume Imaging ◽  
Whole Mount

BackgroundUnderstanding the interactions between tumor and immune cells is critical for improving current immunotherapies. Pre-clinical and clinical evidence has shown that failed T cell infiltration into lung cancer lesions might be associated with low responsiveness towards checkpoint blockade.1 For this reason, it is necessary to characterize not only the phenotype of T cells in tumor-bearing lungs but also their spatial location in the tumor microenvironment (TME). Multiplex immunofluorescence staining allows the simultaneous use of several cell markers to study the state and the spatial location of cell populations in the tissue of interest. Although this technique is usually applied to thin tissue sections (5 to 12 µm), the analysis of large tissue volumes may provide a better understanding of the spatial distribution of cells in relation to the TME. Here, we analyzed the number and spatial distribution of cytotoxic T cells and other immune cells in the TME of tumor-bearing lungs, using both 12 µm sections and whole-mount preparations imaged by confocal microscopy.MethodsLung tumors were induced in C57BL/6 mice by tail vein injection of a cancer cell line derived from KrasG12D/+ and Tp53-/- mice. Lung tissue with a diverse degree of T cell infiltration was collected after 21 days post tumor induction. Tissue was fixed in 4% PFA, followed by snap-frozen for sectioning. Whole-mount preparations were processed according to Weizhe Li et al. (2019) 2 for tissue clearing and multiplex volume imaging. T cells were labeled with CD8 and FOXP3 antibodies to identify cytotoxic or regulatory T cells, respectively. Tumor cells were labeled with a pan-Keratin antibody. Images were acquired using a Leica SP8 confocal microscope. FIJI3 and IMARIS were used for image processing.ResultsWe identified both cytotoxic and regulatory T cell populations in the TME using thin sections and whole-mount. However, using whole-mount after tissue clearing allowed us to better evaluate the spatial distribution of the T cell populations in relation to the tumor structure. Furthermore, tissue clearance facilitates the imaging of larger volumes using multiplex immunofluorescence.ConclusionsAnalysis of large lung tissue volumes provides a better understanding of the location of immune cell populations in relation to the TME and allows to study heterogeneous immune infiltration on a per-lesion base. This valuable information will improve the characterization of the TME and the definition of cancer-immune phenotypes in NSCLC.ReferencesTeng MW, et al., Classifying cancers based on T-cell infiltration and PD-L1. Cancer Res 2015;75(11): p. 2139–45.Li W, Germain RN, and Gerner MY. High-dimensional cell-level analysis of tissues with Ce3D multiplex volume imaging. Nat Protoc 2019;14(6): p. 1708–1733.Schindelin J, et al, Fiji: an open-source platform for biological-image analysis. Nat Methods 2012;9(7): p. 676–82.

T Cells: A Growing Universe of Roles in Neurodegenerative Diseases

2021 ◽  
pp. 107385842110249
Author(s):  
Dallin Dressman ◽  
Wassim Elyaman
Keyword(s):  
T Cells ◽  
T Cell ◽  
Neurodegenerative Diseases ◽  
Human Leukocyte ◽  
Autoimmune Response ◽  
Antigen Specificity ◽  
Risk Genes ◽  
Leukocyte Antigen ◽  
Histocompatibility Complex ◽  
The Central Nervous System

T cells play a central role in homeostasis and host defense against infectious diseases. T cell dysregulation can lead to recognizing self-antigens as foreign antigens, causing a detrimental autoimmune response. T cell involvement in multiple sclerosis (MS), long understood to be an autoimmune-mediated neurodegenerative disease, is well characterized. More recently, a role for T cells has also been identified for the neurodegenerative diseases Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS). Interestingly, several alleles and variants of human leukocyte antigen (HLA) genes have been classified as AD and PD risk genes. HLA codes for components of major histocompatibility complex (MHC) class I or class II, both of which are expressed by microglia, the innate immune cells of the central nervous system (CNS). Thus, both microglia and T cells may potentially interact in an antigen-dependent or independent fashion to shape the inflammatory cascade occurring in neurodegenerative diseases. Dissecting the antigen specificity of T cells may lead to new options for disease-modifying treatments in neurodegenerative diseases. Here, we review the current understanding of T cells in neurodegenerative diseases. We summarize the subsets of T cells, their phenotype and potential functions in animal models and in human studies of neurodegenerative diseases.

scholarly journals Dynamics and Correlates of CD8 T-Cell Counts in Africans with Primary Human Immunodeficiency Virus Type 1 Infection

2016 ◽  
Vol 90 (22) ◽  
pp. 10423-10430 ◽  
Author(s):  
Heather A. Prentice ◽  
Hailin Lu ◽  
Matthew A. Price ◽  
Anatoli Kamali ◽  
Etienne Karita ◽  
...  
Keyword(s):  
T Cells ◽  
Viral Load ◽  
T Cell ◽  
Human Leukocyte ◽  
Neutralizing Antibody ◽  
Sensitivity Analyses ◽  
Supporting Evidence ◽  
Cell Counts ◽  
Cellular And Humoral Immunity ◽  
Hiv 1

ABSTRACT In individuals with HIV-1 infection, depletion of CD4 + T cells is often accompanied by a malfunction of CD8 + T cells that are persistently activated and/or exhausted. While the dynamics and correlates of CD4 counts have been well documented, the same does not apply to CD8 counts. Here, we examined the CD8 counts in a cohort of 497 Africans with primary HIV-1 infection evaluated in monthly to quarterly follow-up visits for up to 3 years in the absence of antiretroviral therapy. Statistical models revealed that (i) CD8 counts were relatively steady in the 3- to 36-month period of infection and similar between men and women; (ii) neither geography nor heterogeneity in the HIV-1 set-point viral load could account for the roughly 10-fold range of CD8 counts in the cohort ( P > 0.25 in all tests); and (iii) factors independently associated with relatively high CD8 counts included demographics (age ≤ 40 years, adjusted P = 0.010) and several human leukocyte antigen class I (HLA-I) alleles, including HLA-A*03:01 ( P = 0.013), B*15:10 ( P = 0.007), and B*58:02 ( P < 0.001). Multiple sensitivity analyses provided supporting evidence for these novel relationships. Overall, these findings suggest that factors associated with the CD8 count have little overlap with those previously reported for other HIV-1-related outcome measures, including viral load, CD4 count, and CD4/CD8 ratio. IMPORTANCE Longitudinal data from 497 HIV-1 seroconverters allowed us to systematically evaluate the dynamics and correlates of CD8 + T-cell counts during untreated primary HIV-1 infection in eastern and southern Africans. Our findings suggest that individuals with certain HLA-I alleles, including A*03 (exclusively A*03:01), persistently maintain relatively high CD8 counts following HIV-1 infection, a finding which may offer an intriguing explanation for the recently reported, negative association of A*03 with HIV-1-specific, broadly neutralizing antibody responses. In future studies, attention to HLA-I genotyping data may benefit in-depth understanding of both cellular and humoral immunity, as well as the intrinsic balances of these types of immunity, especially in settings where there is emerging evidence of antagonism between the two arms of adaptive immunity.

Sign in / Sign up

Export Citation Format

Share Document