Similar Datasets
Project description:Chronic viral infections and tumours are associated with CD8+ T cell exhaustion, which is characterized by high expression of inhibitory receptors such as programmed cell death protein 1 (PD-1) and impaired effector function. Understanding the molecular regulation of T cell exhaustion is critical for the development of new immunotherapies. Chronically activated T cells are maintained by precursors of exhausted T (TPEX) cells that express the transcription factor TCF1, self-renew and give rise to TCF-1– exhausted effector T (TEX) cells; this process is currently, however, poorly understood. Here, we reveal that TPEX cells are heterogenous and contain a population of CD62L+ stem-like exhausted T cells that selectively preserve long-term self-renewal capacity and multipotency of antigen-specific T cells during chronic infection. Furthermore, we show that the transcription factor c-Myb is essential for the development of CD62L+ TPEX cells, self-renewal of TPEX cells and the induction of key features of T cell exhaustion. Consequently, Myb-deficient CD8+ T cells show uninhibited cytokine production resulting in fatal immunopathology in response to chronic but not acute LCMV infection and fail to be maintained long-term. Finally, we show that c-Myb-dependent CD62L+ TPEX cells exclusively mediate T cell proliferation during PD-1 checkpoint inhibition and show enhanced antiviral properties, making them attractive targets for new immunotherapeutic strategies. Thus, our findings identify CD62L+ TPEX cells as central to the maintenance of exhausted T cell responses and reveal c-Myb as a key transcriptional orchestrator that combines two central aspects of T cell exhaustion, limitation of T cell function and long-term maintenance during chronic infection.
2022-08-22 | GSE203575 | GEO
Project description:Chronic viral infections and tumours are associated with CD8+ T cell exhaustion, which is characterized by high expression of inhibitory receptors such as programmed cell death protein 1 (PD-1) and impaired effector function. Understanding the molecular regulation of T cell exhaustion is critical for the development of new immunotherapies. Chronically activated T cells are maintained by precursors of exhausted T (TPEX) cells that express the transcription factor TCF1, self-renew and give rise to TCF-1– exhausted effector T (TEX) cells; this process is currently, however, poorly understood. Here, we reveal that TPEX cells are heterogenous and contain a population of CD62L+ stem-like exhausted T cells that selectively preserve long-term self-renewal capacity and multipotency of antigen-specific T cells during chronic infection. Furthermore, we show that the transcription factor c-Myb is essential for the development of CD62L+ TPEX cells, self-renewal of TPEX cells and the induction of key features of T cell exhaustion. Consequently, Myb-deficient CD8+ T cells show uninhibited cytokine production resulting in fatal immunopathology in response to chronic but not acute LCMV infection and fail to be maintained long-term. Finally, we show that c-Myb-dependent CD62L+ TPEX cells exclusively mediate T cell proliferation during PD-1 checkpoint inhibition and show enhanced antiviral properties, making them attractive targets for new immunotherapeutic strategies. Thus, our findings identify CD62L+ TPEX cells as central to the maintenance of exhausted T cell responses and reveal c-Myb as a key transcriptional orchestrator that combines two central aspects of T cell exhaustion, limitation of T cell function and long-term maintenance during chronic infection.
2022-08-22 | GSE199839 | GEO
Project description:c-Myb instructs both stemness and functional exhaustion of CD8+ T cells during chronic infection
| PRJNA846703 | ENA
Project description:c-Myb instructs both stemness and functional exhaustion of CD8+ T cells during chronic infection [bulkRNA-seq]
| PRJNA841475 | ENA
Project description:c-Myb instructs both stemness and functional exhaustion of CD8+ T cells during chronic infection [scRNA-seq]
| PRJNA821678 | ENA
Project description:T cell exhaustion often occurs during chronic infection and prevents optimal viral control. The molecular pathways involved in T cell exhaustion remain poorly understood. Here we show that exhausted CD8+ T cells are subject to complex layers of negative regulation resulting from the coexpression of multiple inhibitory receptors. Exhausted CD8+ T cells expressed up to seven inhibitory receptors. Coexpression of multiple distinct inhibitory receptors was associated with greater T cell exhaustion and more severe infection. Regulation of T cell exhaustion by various inhibitory pathways was nonredundant, as blockade of the T cell inhibitory receptors PD-1 and LAG-3 simultaneously and synergistically improved T cell responses and diminished viral load in vivo. Thus, CD8+ T cell responses during chronic viral infections are regulated by complex patterns of coexpressed inhibitory receptors.
| S-EPMC2605166 | biostudies-literature
Project description:Inhibitory receptors play a crucial role in regulating CD8 T-cell function during chronic viral infection. T-cell Ig- and mucin-domain-containing molecule-3 (Tim-3) is well known to negatively regulate T-cell responses, but its role in CD8 T-cell exhaustion during chronic infection in vivo remains unclear. In this study, we document coregulation of CD8 T cell exhaustion by Tim-3 and PD-1 during chronic lymphocytic choriomeningitis virus infection. Whereas Tim-3 was only transiently expressed by CD8 T cells after acute infection, virus-specific CD8 T cells retained high Tim-3 expression throughout chronic infection. The majority (approximately 65% to 80%) of lymphocytic choriomeningitis virus-specific CD8 T cells in lymphoid and nonlymphoid organs coexpressed Tim-3 and PD-1. This coexpression of Tim-3 and PD-1 was associated with more severe CD8 T-cell exhaustion in terms of proliferation and secretion of effector cytokines such as IFN-gamma, TNF-alpha, and IL-2. Interestingly, CD8 T cells expressing both inhibitory receptors also produced the suppressive cytokine IL-10. Most importantly, combined blockade of Tim-3 and PD-1 pathways in vivo synergistically improved CD8 T cell responses and viral control in chronically infected mice. Taken together, our study defines a parameter for determining the severity of CD8 T cell dysfunction and for identifying virus-specific CD8 T cells that produce IL-10, and shows that targeting both PD-1 and Tim-3 is an effective immune strategy for treating chronic viral infections.
| S-EPMC2930455 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2024-03-06 | GSE234309 | GEO
Project description:BackgroundA functional cure for chronic HBV could be achieved by boosting HBV-specific immunity. In vitro studies show that immunotherapy could be an effective strategy. However, these studies include strategies to enrich HBV-specific CD8 T cells, which could alter the expression of the anti-PD-1/anti-PD-L1 antibody targets. Our aim was to determine the efficacy of PD-L1 blockade ex vivo.MethodsHBV-specific CD8 T cells were characterized ex vivo by flow cytometry for the simultaneous analysis of six immune populations and 14 activating and inhibitory receptors. Ex vivo functionality was quantified by ELISpot and by combining peptide pool stimulation, dextramers and intracellular flow cytometry staining.ResultsThe functionality of HBV-specific CD8 T cells is associated with a higher frequency of cells with low exhaustion phenotype (LAG3-TIM3-PD-1+), independently of the clinical parameters. The accumulation of HBV-specific CD8 T cells with a functionally exhausted phenotype (LAG3+TIM3+PD-1+) is associated with lack of ex vivo functionality. PD-L1 blockade enhanced the HBV-specific CD8 T cell response only in patients with lower exhaustion levels, while response to PD-L1 blockade was abrogated in patients with higher frequencies of exhausted HBV-specific CD8 T cells.ConclusionHigher levels of functionally exhausted HBV-specific CD8 T cells are associated with a lack of response that cannot be restored by blocking the PD-1:PD-L1 axis. This suggests that the clinical effectiveness of blocking the PD-1:PD-L1 axis as a monotherapy may be restricted. Combination strategies, potentially including the combination of anti-LAG-3 with other anti-iR antibodies, will likely be required to elicit a functional cure for patients with high levels of functionally exhausted HBV-specific CD8 T cells.
| S-EPMC8473828 | biostudies-literature
Project description:Prolonged exposure of CD8+ T cells to antigenic stimulation, as in chronic viral infections, leads to a state of diminished function termed exhaustion. We now demonstrate that even during exhaustion there is a subset of functional CD8+ T cells defined by surface expression of SIRPα, a protein not previously reported on lymphocytes. On SIRPα+ CD8+ T cells, expression of co-inhibitory receptors is counterbalanced by expression of co-stimulatory receptors and it is only SIRPα+ cells that actively proliferate, transcribe IFNγ and show cytolytic activity. Furthermore, target cells that express the ligand for SIRPα, CD47, are more susceptible to CD8+ T cell-killing in vivo. SIRPα+ CD8+ T cells are evident in mice infected with Friend retrovirus, LCMV Clone 13, and in patients with chronic HCV infections. Furthermore, therapeutic blockade of PD-L1 to reinvigorate CD8+ T cells during chronic infection expands the cytotoxic subset of SIRPα+ CD8+ T cells.
| S-EPMC6377614 | biostudies-literature