scholarly journals Reduction and Functional Exhaustion of T Cells in Patients with Coronavirus Disease 2019 (COVID-19)

2020 ◽  
Author(s):  
Bo Diao ◽  
Chenhui Wang ◽  
Yingjun Tan ◽  
Xiewan Chen ◽  
Ying Liu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Critical Role ◽  
T Cell Subsets ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Cell Counts ◽  
Tnf Α ◽  
Functional Exhaustion ◽  
Routine Physical Examination

SummaryBACKGROUNDThe outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed great threat to human health, which has been declared a public health emergency of international concern (PHEIC) by the WHO. T cells play a critical role in antiviral immunity but their numbers and functional state in COVID-19 patients remain largely unclear.METHODSWe retrospectively reviewed the counts of total T cells, CD4+, CD8+ T cell subsets, and serum cytokine concentration from inpatient data of 522 patients with laboratory-confirmed COVID-19, admitted into two hospitals in Wuhan from December 2019 to January 2020, and 40 healthy controls, who came to the hospitals for routine physical examination. In addition, the expression of T cell exhaustion markers PD-1 and Tim-3 were measured by flow cytometry in the peripheral blood of 14 COVID-19 cases.RESULTSThe number of total T cells, CD4+ and CD8+ T cells were dramatically reduced in COVID-19 patients, especially among elderly patients (⩾60 years of age) and in patients requiring Intensive Care Unit (ICU) care. Counts of total T cells, CD8+T cells or CD4+T cells lower than 800/μL, 300/μL, or 400/μL, respectively, are negatively correlated with patient survival. Statistical analysis demonstrated that T cell numbers are negatively correlated to serum IL-6, IL-10 and TNF-α concentration, with patients in decline period showing reduced IL-6, IL-10 and TNF-α concentrations and restored T cell counts. Finally, T cells from COVID-19 patients have significantly higher levels of the exhausted marker PD-1 as compared to health controls. Moreover, increasing PD-1 and Tim-3 expression on T cells could be seen as patients progressed from prodromal to overtly symptomatic stages, further indicative of T cell exhaustion.CONCLUSIONST cell counts are reduced significantly in COVID-19 patients, and the surviving T cells appear functionally exhausted. Non-ICU patients, with total T cells, CD8+T cells CD4+T cells counts lower than 800/μL, 300/μL, and 400/μL, respectively, may still require aggressive intervention even in the immediate absence of more severe symptoms due to a high risk for further deterioration in condition.

scholarly journals 644 Tumor-mediated suppressive signaling and hypoxia supports altered chromatin landscapes that limit the transcriptional and functional potential of terminal T cell exhaustion

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A673-A673
Author(s):  
Rhodes Ford ◽  
Natalie Rittenhouse ◽  
Nicole Scharping ◽  
Paolo Vignali ◽  
Greg Delgoffe ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
Tumor Microenvironment ◽  
Histone Modifications ◽  
Cd8 T Cells ◽  
Tumor Hypoxia ◽  
T Cell Subsets ◽  
T Cell Exhaustion ◽  
Cell Exhaustion

BackgroundCD8+ T cells are a fundamental component of the anti-tumor response; however, tumor-infiltrating CD8+ T cells (TIL) are rendered dysfunctional by the tumor microenvironment. CD8+ TIL display an exhausted phenotype with decreased cytokine expression and increased expression of co-inhibitory receptors (IRs), such as PD-1 and Tim-3. The acquisition of IRs mark the progression of dysfunctional TIL from progenitors (PD-1Low) to terminally exhausted (PD-1+Tim-3+). How the chromatin landscape changes during this progression has not been described.MethodsUsing a low-input ChIP-based assay called Cleavage Under Targets and Release Using Nuclease (CUT&RUN), we have profiled the histone modifications at the chromatin of tumor-infiltrating CD8+ T cell subsets to better understand the relationship between the epigenome and the transcriptome as TIL progress towards terminal exhaustion.ResultsWe have identified two epigenetic characteristics unique to terminally exhausted cells. First, we have identified a unique set of genes, characterized by active histone modifications that do not have correlated gene expression. These regions are enriched for AP-1 transcription factor motifs, yet most AP-1 family factors are actively downregulated in terminally exhausted cells, suggesting signals that promote downregulation of AP-1 expression negatively impacts gene expression. We have shown that inducing expression of AP-1 factors with a 41BB agonist correlates with increased expression of these anticorrelated genes. We have also found a substantial increase in the number of genes that exhibit bivalent chromatin marks, defined by the presence of both active (H3K4me3) and repressive (H3K27me3) chromatin modifications that inhibit gene expression. These bivalent genes in terminally exhausted T cells are not associated with plasticity and represent aberrant hypermethylation in response to tumor hypoxia, which is necessary and sufficient to promote downregulation of bivalent genes.ConclusionsOur study defines for the first time the roles of costimulation and the tumor microenvironment in driving epigenetic features of terminally exhausted tumor-infiltrating T cells. These results suggest that terminally exhausted T cells have genes that are primed for expression, given the right signals and are the basis for future work that will elucidate that factors that drive progression towards terminal T cell exhaustion at the epigenetic level and identify novel therapeutic targets to restore effector function of tumor T cells and mediate tumor clearance.

scholarly journals Critical Role for Alpha/Beta and Gamma Interferons in Persistence of Lymphocytic Choriomeningitis Virus by Clonal Exhaustion of Cytotoxic T Cells

2001 ◽  
Vol 75 (18) ◽  
pp. 8407-8423 ◽  
Author(s):  
Rong Ou ◽  
Shenghua Zhou ◽  
Lei Huang ◽  
Demetrius Moskophidis
Keyword(s):  
T Cells ◽  
T Cell ◽  
Critical Role ◽  
Lymphocytic Choriomeningitis ◽  
Lymphocytic Choriomeningitis Virus ◽  
Interferon Response ◽  
Type I ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Alpha Beta

ABSTRACT Under conditions of high antigenic load during infection with invasive lymphocytic choriomeningitis virus (LCMV) strains, virus can persist by selective clonal exhaustion of antigen-specific CD8+ T cells. In this work we studied the down-regulation of the virus-specific CD8+-T-cell response during a persistent infection of adult mice, with particular emphasis on the contribution of the interferon response in promoting host defense. Studies were conducted by infecting mice deficient in receptors for type I (alpha/beta interferon [IFN-α/β]), type II (IFN-γ), and both type I and II IFNs with LCMV isolates that vary in their capacity to induce T-cell exhaustion. The main conclusions of this study are as follows. (i) IFNs play a critical role in LCMV infection by reducing viral loads in the initial stages of infection and thus modifying both the extent of CD8+-T-cell exhaustion and the course of infection. The importance of IFNs in this context varies with the biological properties of the LCMV strain. (ii) An inverse correlation exists between antigen persistence and responsiveness of virus-specific CD8+ T cells. This results in distinct programs of activation or tolerance (functional unresponsiveness and/or physical elimination of antigen-specific cells) during acute and chronic virus infections, respectively. (iii) A successful immune response associated with definitive viral clearance requires an appropriate balance between cellular and humoral components of the immune system. We discuss the role of IFNs in influencing virus-specific T cells that determine the outcome of persistent infections.

PD-1+ T Cell Subsets in Follicular Lymphoma Tumor Microenvironment and Their Implications for Prognosis and Therapy

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2648-2648
Author(s):  
Fuliang Chu ◽  
Wencai Ma ◽  
Tomohide Yamazaki ◽  
Myriam Foglietta ◽  
Durga Nattama ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
T Cells ◽  
T Cell ◽  
Follicular Lymphoma ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
T Cell Subsets ◽  
Prognostic Impact ◽  
T Cell Exhaustion ◽  
Cell Exhaustion

Abstract Abstract 2648 Background: Programmed death (PD)-1, a coinhibitory receptor expressed by effector T cells (Teffs) is highly expressed on intratumoral T cells (mean 61%, range 34–86% for CD4+ T cells and mean 44%, range 31–69% for CD8+ T cells) in follicular lymphoma (FL), a finding associated with impaired ability to recognize autologous tumor (Nattamai et al, ASH 2007). Hence, PD-1 expression would be expected to confer an unfavorable prognosis in FL. However, correlation of PD-1 with clinical outcome in FL has been inconsistent with two studies showing favorable (Carreras et al, J Clin Oncol 2009; Wahlin et al, Clin Cancer Res 2010) and one study showing unfavorable (Richendollar et al, Hum Pathol 2011) outcome. While differences in method of analysis and type of treatment may explain the disparate results, a more complex model may be necessary to understand the prognostic impact of PD-1 in FL as PD-1 is expressed not only on antitumor Teffs but also on protumor follicular helper T cells (Tfh) and regulatory T cells (Tregs). Methods: To determine the nature of PD-1+ T cells in FL we performed comprehensive genomic and immunologic studies. By flow cytometry, we observed that the intratumoral CD4+ T cells in FL may be categorized into 3 subsets based on PD-1 expression - PD-1 high (PD-1hi), intermediate (PD-1int), and low (PD-1lo). The intratumoral CD8+ T cells consisted of PD-1int and PD-1lo subsets. The 3 CD4+ T cell subsets were FACSorted from FL tumors (n=3) and whole genome gene expression profiling (GEP) was performed. T cell subsets sorted similarly from tonsils served as controls for reactive follicular hyperplasia (FH) (n=3). Differentially expressed genes in GEP studies were confirmed at the mRNA level by real-time PCR (n=5) and at the protein level by flow cytometry when antibodies were available (n=5–10). Results: Our results suggested that CD4+PD-1hi T cells are Tfh cells (CXCR5hiBcl6hi ICOShiCD40LhiSAPhiPRDM1loIL-4hiIL-21hi); the CD4+PD-1int T cells consisted of a mixture of activated Teffs (CD45RO+CD45RA−) including Th1 (Tbet+IFNg+), Th2 (IL-10+), and Th17 cells (RORc+IL-17+), and Tregs (Foxp3+CD25hiCD127lo); and the CD4+PD-1lo T cells consisted of a mixture of activated Teffs (CD45RO+CD45RA− but IFNg−IL-4−IL-10−IL-17−), Tregs, and naïve T cells (CD45RO−CD45RA+CCR7+). Although these subsets were present in both FL and FH, there were important differences. IL-4 expression was significantly higher in Tfh in FL vs. FH and may play a role in the pathogenesis of FL. IL-17 expression was low and expression of coinhibitory molecules BTLA and CD200 was high in CD4+PD-1int T cells in FL vs. FH. BTLA and CD200 were also increased in CD8+PD-1int T cells in FL vs. FH. However, other coinhibitory molecules (LAG-3, Tim-3, CD160, CTLA-4, CD244, KLRG1) were not significantly different between FL and FH. CD4+PD-1int T cells also had higher expression of BATF, a transcription factor associated with T cell exhaustion in FL vs. FH. Together, these results suggest that the CD4+PD-1int T cells in FL may be in a state of T cell exhaustion whereas the CD4+PD-1int T cells in FH may represent recently activated Teffs. Consistent with this, blocking PD-1 with anti-PD-1 blocking antibody significantly enhanced proliferation and the production of Th1 (IFNg, TNFa) but not Th2 (IL-4, IL-5, IL-10, IL-13) cytokines by intratumoral CD4+ and CD8+ T cells in response to stimulation with autologous FL tumor cells (n=3). As expected, Tregs were increased in number in FL vs. FH and were present in the PD-1int and PD-1lo T cell subsets. We found 74% (range 40–97%) of FL Tregs expressed PD-1. Among the CD4+PD-1lo and CD8+PD-1lo T cells, there were more activated Teffs and fewer naïve T cells in FL vs. FH. Conclusions: Our results suggest that the PD-1+ T cells in FL are comprised of a mixture of antitumor Teffs and protumor Tfh and Tregs. The prognostic impact of PD-1+ T cells in FL may dependent on the relative frequency of these subsets as ligation of PD-1 may produce favorable (inhibition of protumor Tfh and Tregs) or unfavorable (inhibition of antitumor Teffs) outcomes by inhibiting or promoting tumor growth, respectively. Conversely, our results imply that agents that block PD-1/PD-ligand pathway may have the opposite effect on these T cell subsets and enumeration of the intratumoral PD-1+ T cell subsets may serve as biomarker to predict response to these agents in FL and possibly other B-cell malignancies. Disclosures: Dong: GSK: Consultancy; Genentech: Honoraria; Tempero: Consultancy; Ono: Consultancy; AnaptysBio: Consultancy. Neelapu:Cure Tech Ltd: Research Funding.

scholarly journals Distinct Immune Profiles of Exhausted Effector and Memory CD8+ T Cells in Individuals With Filarial Lymphedema

2021 ◽  
Vol 11 ◽  
Author(s):  
Sacha Horn ◽  
Dennis Borrero-Wolff ◽  
Manuel Ritter ◽  
Kathrin Arndts ◽  
Anna Wiszniewsky ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Viral Infections ◽  
Wuchereria Bancrofti ◽  
T Cell Subsets ◽  
T Cell Exhaustion ◽  
Memory Cd8 T Cells ◽  
Cell Exhaustion ◽  
And Control ◽  
Control Management

CD8+ T cells are crucial for the clearance of viral infections, and current research begins to highlight their importance in parasitic diseases too. In-depth research about characteristics of CD8+ T-cell subsets and exhaustion remains uncertain, especially during filariasis, a chronic helminth infection. Lymphatic filariasis, elicited by Wuchereria bancrofti, remains a serious health problem in endemic areas in Ghana, especially in those suffering from morbidity due to lymphedema (LE). In this observational study, the characteristics and profiles of CD8+ T cells were compared between asymptomatic Wuchereria bancrofti-infected individuals, uninfected endemic normals, and those with LE (grades 2–6). Focusing on exhausted memory (CD8+exmem: CD8+ T-betdimEomeshi) and effector (CD8+exeff: CD8+T-bethiEomesdim) CD8+ T-cell subsets, advanced flow cytometry revealed that LE individuals presented reduced frequencies of IFN-γ+CD8+exmem T cells expressing Tim-3 or LAG-3 which negatively correlated to the presence of LE. Moreover, the LE cohort further showed significantly higher frequencies of IL-10+CD8+exeff T cells expressing either Tim-3, LAG-3, CD39, KLRG-1, or PD-1, all associated markers of exhaustion, and that these frequencies positively correlated with the presence of LE. In summary, this study shows that distinct exhausted CD8+ T-cell subsets are prominent in individuals suffering from LE, suggesting that enhanced inflammation and constant immune activation might drive exhaustion of CD8+ T cells. Since T-cell exhaustion is known to be associated with insufficient control of persisting antigen, the data presented here reveals that these CD8+ T-cell exhaustion patterns in filarial LE should be taken into consideration for prevention and control management of LE.

scholarly journals 518 Epigenetic dysfunction of terminally exhausted tumor infiltrating T cells

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A554-A554
Author(s):  
Rhodes Ford ◽  
Paolo Vignali ◽  
Natalie Rittenhouse ◽  
Nicole Scharping ◽  
Andrew Frisch ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Transcription Factors ◽  
T Cell ◽  
Regulation Of Gene Expression ◽  
Tumor Hypoxia ◽  
T Cell Subsets ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Drive Gene

BackgroundTumor-infiltrating CD8+ T cells have been characterized by their exhausted phenotype with decreased cytokine expression and increased expression of co-inhibitory receptors, such as PD-1 and Tim-3. These receptors mark the progression towards exhaustion from a progenitor stage (PD-1Low) to a terminally exhausted stage (PD-1+Tim-3+). While the epigenetics of tumor-infiltrating T cells are unique compared to naïve, effector, and memory populations, how the chromatin landscape changes during this progression has not been described.MethodsUsing a low-input ChIP-based assay called Cleavage Under Targets and Release Using Nuclease (CUT&RUN), we profiled the histone modifications at the chromatin of tumor-infiltrating CD8+ T cell subsets to better understand the relationship between the epigenome and the transcriptome as TIL progress towards terminal exhaustion.ResultsWe have identified two epigenetic characteristics unique to terminally exhausted cells. First, we found a substantial increase in the number of genes that exhibit bivalent chromatin marks, defined by the presence of both activating (H3K4me3) and repressive (H3K27me3) epigenetic modifications that inhibit gene expression. In contrast to stem cells which exhibit bivalency, bivalent genes in terminally exhausted T cells are not associated with plasticity and represent aberrant hypermethylation in response to tumor hypoxia. Secondly, we have also identified a unique set of enhancers, characterized by H3K27ac that do not drive gene expression. These enhancers are enriched for AP-1 transcription factors, whereas enhancers that correlate with gene transcription are enriched for nuclear receptor (NR) transcription factors. Intriguingly, while most AP-1 and NR transcription factors are not expressed in terminally exhausted cells, we found that Batf, an inhibitory AP-1 family member, and Nr4a2, a NR known to promote both exhaustion and modify chromatin were specifically expressed in terminally exhausted cells. These data suggest the balance of Batf and Nr4a2 may modulate the enhancer landscape to promote terminal exhaustion, while hypoxia simultaneously promotes hypermethylation and gene repression.ConclusionsOur study defines for the first time the features of epigenetic dysfunction in tumor-mediated T cell exhaustion and deepens our understanding of the epigenetic regulation of gene expression. These observations are the bases for future work that will elucidate that factors that drive progression towards terminal T cell exhaustion at the epigenetic level and identify novel therapeutic targets to restore effector function of tumor T cells and mediate tumor clearance.

scholarly journals Filarial Lymphedema Patients Are Characterized by Exhausted CD4+ T Cells

2022 ◽  
Vol 11 ◽  
Author(s):  
Sacha Horn ◽  
Manuel Ritter ◽  
Kathrin Arndts ◽  
Dennis Borrero-Wolff ◽  
Anna Wiszniewsky ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Expression Patterns ◽  
Wuchereria Bancrofti ◽  
T Cell Subsets ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Management Measures ◽  
Disability Adjusted Life ◽  
Life Years

Worldwide, more than 200 million people are infected with filariae which can cause severe symptoms leading to reduced quality of life and contribute to disability-adjusted life years (DALYs). In particular, lymphatic filariasis (LF) caused by Wuchereria bancrofti can lead to lymphedema (LE) and consequently presents a serious health problem. To understand why only a fraction of the infected individuals develop pathology, it is essential to understand how filariae regulate host immunity. The central role of T cells for immunity against filariae has been shown in several studies. However, there is little knowledge about T cell exhaustion, which causes T cell dysfunction and impaired immune responses, in this group of individuals. Recently, we showed that LE patients from Ghana harbor distinct patterns of exhausted effector and memory CD8+ T cell subsets. Based on these findings, we now characterized CD4+ T cell subsets from the same Ghanaian patient cohort by analyzing distinct markers within a 13-colour flow cytometry panel. We revealed that LE patients had increased frequencies of CD4+ T cells expressing exhaustion-associated receptors such as KLRG-1, TIM-3 and PD-1 compared to healthy endemic normal and W. bancrofti-infected individuals. Moreover, CD4+ T cells in LE patients were characterized by distinct co-expression patterns of inhibitory receptors. Collectively with the previous findings on CD8+ T cell exhaustion patterns, the data shown here demonstrates that filarial LE patients harbor distinct subsets of exhausted T cells. Thus, T cell exhaustion patterns in LE patients need attention especially in regards to susceptibility of concomitant infections and should be taken into consideration for LE management measures.

scholarly journals Blimp-1–mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis

2016 ◽  
Vol 213 (9) ◽  
pp. 1799-1818 ◽  
Author(s):  
SuJin Hwang ◽  
Dustin A. Cobb ◽  
Rajarshi Bhadra ◽  
Ben Youngblood ◽  
Imtiaz A. Khan
Keyword(s):  
T Cells ◽  
T Cell ◽  
Critical Role ◽  
Cd8 T Cell ◽  
Cd4 T Cell ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Cell Dysfunction ◽  
T Cell Dysfunction

CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)–susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell–intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches.

scholarly journals Mechanisms of T-Cell Exhaustion in Pancreatic Cancer

Cancers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2274
Author(s):  
Didem Saka ◽  
Muazzez Gökalp ◽  
Betül Piyade ◽  
Nedim Can Cevik ◽  
Elif Arik Sever ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Checkpoint ◽  
Immune Checkpoint Inhibitors ◽  
Checkpoint Inhibitors ◽  
Critical Role ◽  
Single Agent ◽  
T Cell Exhaustion ◽  
Inhibitory Receptors ◽  
Cell Exhaustion

T-cell exhaustion is a phenomenon that represents the dysfunctional state of T cells in chronic infections and cancer and is closely associated with poor prognosis in many cancers. The endogenous T-cell immunity and genetically edited cell therapies (CAR-T) failed to prevent tumor immune evasion. The effector T-cell activity is perturbed by an imbalance between inhibitory and stimulatory signals causing a reprogramming in metabolism and the high levels of multiple inhibitory receptors like programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), and Lymphocyte-activation gene 3 (Lag-3). Despite the efforts to neutralize inhibitory receptors by a single agent or combinatorial immune checkpoint inhibitors to boost effector function, PDAC remains unresponsive to these therapies, suggesting that multiple molecular mechanisms play a role in stimulating the exhaustion state of tumor-infiltrating T cells. Recent studies utilizing transcriptomics, mass cytometry, and epigenomics revealed a critical role of Thymocyte selection-associated high mobility group box protein (TOX) genes and TOX-associated pathways, driving T-cell exhaustion in chronic infection and cancer. Here, we will review recently defined molecular, genetic, and cellular factors that drive T-cell exhaustion in PDAC. We will also discuss the effects of available immune checkpoint inhibitors and the latest clinical trials targeting various molecular factors mediating T-cell exhaustion in PDAC.

scholarly journals T Cell Exhaustion and Senescence in Epstein-Barr Virus-Associated Lymphoma Patients

2020 ◽  
Author(s):  
Huihui Liu ◽  
Junhui Xu ◽  
Lihong Wang ◽  
Wenjun Mao ◽  
Bingjie Wang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Peripheral Blood ◽  
Epstein Barr Virus ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Barr Virus ◽  
Cell Counts ◽  
Healthy Donors ◽  
Epstein Barr

Abstract Background The Epstein-Barr Virus (EBV) is tumorigenic, and can be detected in many kinds of lymphomas. Some studies have shown a worse prognosis for patients with EBV-associated lymphoma. However, the mechanism is not fully understood. This study aimed to investigate the T cell signatures in patients with EBV-associated lymphoma. Methods Peripheral blood was collected from 17 patients with EBV-associated lymphoma and 19 healthy donors. We first examined the proportions of the lymphocyte subpopulations in peripheral blood mononuclear cells in patients with both groups by flow cytometry. Then we employed the enzyme-linked immunospot assay to evaluate the EBV antigen-specific response of the cytotoxic T cells in the two groups. Finally, to explore the mechanism of T cells dysfunction in EBV-associated lymphoma, we examined the expression of multiple inhibitory receptors representing T cell exhaustion and biomarkers representing T cell senescence on the surfaces of CD4+ T cells and CD8+ T cells. Results The ratio of peripheral CD4+ T cells and the absolute cell counts of CD4+ T cells and CD8+ T cells were significantly decreased in patients with EBV-associated lymphoma compared with those of healthy donors. The IFN-γ production upon stimulation of EBV mixed peptides were remarkably reduced in the patients. Higher expression levels of T cell exhaustion markers, PD1, LAG3, TIM3 and CTLA4 on T cells were found in the patients. The two subsects of exhausted T cells (T-bethiPD1mid and EOMEShiPD1hi) were higher in the patients. More importantly, CXCR5+CD8+T cells controlling viral replication decreased significantly in the patients. The fractions of senescent T cells increased in the patients. Conclusions In summary, our study demonstrated that the reduced EBV-specific T cells, the exhaustion and senescence of T cells together contributed to the T cell dysfunction in the patients with EBV-associated lymphoma.

scholarly journals Exhausting T Cells During HIV Infection May Improve the Prognosis of Patients with COVID-19

2021 ◽  
Vol 11 ◽  
Author(s):  
Hua-Song Lin ◽  
Xiao-Hong Lin ◽  
Jian-Wen Wang ◽  
Dan-Ning Wen ◽  
Jie Xiang ◽  
...  
Keyword(s):  
T Cells ◽  
Immune System ◽  
T Cell ◽  
Cd4 T Cell ◽  
T Cell Exhaustion ◽  
Hiv Patients ◽  
Aids Patients ◽  
Cell Exhaustion ◽  
Cell Counts ◽  
Hiv Aids

T-cell reduction is an important characteristic of coronavirus disease 2019 (COVID-19), and its immunopathology is a subject of debate. It may be due to the direct effect of the virus on T-cell exhaustion or indirectly due to T cells redistributing to the lungs. HIV/AIDS naturally served as a T-cell exhaustion disease model for recognizing how the immune system works in the course of COVID-19. In this study, we collected the clinical charts, T-lymphocyte analysis, and chest CT of HIV patients with laboratory-confirmed COVID-19 infection who were admitted to Jin Yin-tan Hospital (Wuhan, China). The median age of the 21 patients was 47 years [interquartile range (IQR) = 40–50 years] and the median CD4 T-cell count was 183 cells/μl (IQR = 96–289 cells/μl). Eleven HIV patients were in the non-AIDS stage and 10 were in the AIDS stage. Nine patients received antiretroviral treatment (ART) and 12 patients did not receive any treatment. Compared to the reported mortality rate (nearly 4%–10%) and severity rate (up to 20%–40%) among COVID-19 patients in hospital, a benign duration with 0% severity and mortality rates was shown by 21 HIV/AIDS patients. The severity rates of COVID-19 were comparable between non-AIDS (median CD4 = 287 cells/μl) and AIDS (median CD4 = 97 cells/μl) patients, despite some of the AIDS patients having baseline lung injury stimulated by HIV: 7 patients (33%) were mild (five in the non-AIDS group and two in the AIDS group) and 14 patients (67%) were moderate (six in the non-AIDS group and eight in the AIDS group). More importantly, we found that a reduction in T-cell number positively correlates with the serum levels of interleukin 6 (IL-6) and C-reactive protein (CRP), which is contrary to the reported findings on the immune response of COVID-19 patients (lower CD4 T-cell counts with higher levels of IL-6 and CRP). In HIV/AIDS, a compromised immune system with lower CD4 T-cell counts might waive the clinical symptoms and inflammatory responses, which suggests lymphocyte redistribution as an immunopathology leading to lymphopenia in COVID-19.

Sign in / Sign up

Export Citation Format

Share Document