Spatial regulation of CD8+ T cells at the HLA-E-NKG2A axis drives HIV persistence in Lymph Node B Cell Follicles
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1263523 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:B cell follicles (BCF) in the lymph node are a major sanctuary for HIV reservoirs. Immune regulatory mechanisms hindering cytolytic CD8+ responses at these sites, are poorly characterized, likely enabling HIV persistence. Spatial transcriptomics and high- dimensional histocytometry were used to define CD8+ T cell function and immune regulation in LN follicles of people Living with HIV (PLWH), at various stages of ART- treatment. Histocytometry demonstrated that CD8+ T cells infiltrating BCF mostly lacked granzyme B expression, coinciding with reduced chromatin access at cytolytic gene loci in dissociated lymph node cells. Spatial transcriptomics confirmed the immune regulatory microenvironment of HIV-infected BCF, particularly exhibiting upregulation of HLA-E. Additional FACS analysis identified a subset of LN CD8+ T cells expressing the NKG2A-interacting partner of HLA-E, with reduced granzyme B expression. These findings reveal regulation of follicular CD8+ T cells at the HLA-E- NKG2A axis as a key mechanism for HIV immune evasion.
2025-08-26 | GSE297327 | GEO
Project description:New targets that enhance anti-tumor immunity must be identified to improve the efficacy of cancer immunotherapy. Here we show that loss of endoplasmic reticulum aminopeptidase (ERAP) family proteins improves anti-tumor immunity and synergizes with immune checkpoint blockade. Mechanistically, we show that loss of ERAP inactivates the HLA-E/NKG2A checkpoint, which normally restrains tumor killing by both CD8+ T cells and NK cells. The inhibitory activity of HLA-E is dependent on its presentation of a restricted set of invariant epitopes which form the binding surface for the NKG2A/CD94 receptor complex. Using genetic screening, in vivo models, cell-based assays, and immunopeptidomics, we show that loss of ERAP activity prevents the processing of these invariant peptides and alters the presented peptidome of both HLA-E and classical MHC-I. HLA-E neo-peptides presented after ERAP deletion are unable to bind the NKG2A/CD94 receptor, rendering tumor cells highly susceptible to killing by NKG2A+ cytotoxic T and NK cells. Thus, loss of ERAP phenocopies the loss or inhibition of the HLA-E/NKG2A pathway and represents an attractive therapeutic approach to inhibit this critical checkpoint. More broadly, this work identifies ERAP1/2 as druggable intracellular enzymes that could be targeted using small molecules to inactivate a cell-surface inhibitory pathway and represents a novel approach to therapeutic modulation of immune responses.
2024-11-21 | PXD052031 | Pride
Project description:Tingible body macrophages (TBMs) exist in lymph node B cell follicles and are responsible for clearing apoptotic B cells. Our data suggests that TBMs are of Cd169-lineage. We isolated cells from Cd169Cre/+.Tdtomatofl/fl reporter mice and transcriptionally profiled them to identify putative TBMs and chacterise their development and function relative to other LN cells of the Cd169 lineage.
2023-02-16 | GSE214060 | GEO
Project description:Checkpoint blockage has revolutionized cancer treatment. NKG2A is an inhibitory receptor expressed by cytotoxic lymphocytes, including NK cells. In contrast to other checkpoint inhibitory antibodies, anti-NKG2A antibodies have shown only limited success. Here, we designed a Cas9-based strategy to delete KLRC1 from human NK cells. Electroporation of KLRC1-targeting Cas9-RNP efficiently eliminated NKG2A expression from primary human NK cells. NKG2A-deficient NK cells showed normal proliferation, only minor transcriptional changes related to enhanced NK cell activation and maintained their phenotype and licensing status. Genetic deletion of NKG2A fully bypassed HLA-E inhibition and further enhanced NK cell activity against various tumor cell lines, thereby outperforming anti-NKG2A antibodies. In combination with antibody-coating of tumor cells to induce antibody-dependent cellular cytotoxicity, genetic deletion of NKG2A independently promoted cytotoxicity. Thus, Cas9-mediated targeting of NKG2A is an effective way to target this important inhibitory checkpoint. This technique is easily amenable to adoptive cell therapy in the clinical setting, where NKG2A deletion will promote anti-tumor responses and may help NK cells to better infiltrate and persist in an inhibitory tumor microenvironment.
2021-09-01 | GSE178566 | GEO
Project description:In this study we focussed our investigations on ECM remodelling by FRCs during lymph node (LN) expansion, and the interconnection between the cellular and ECM components of the conduit network. We demonstrate a loss of ECM components of the conduit during acute LN expansion
2021-05-11 | PXD015816 | Pride
Project description:The comprehensive characterization and quantification of the HIV tissue reservoirs is required to design appropriate therapeutic intervention(s) to achieve a cure. While pioneering studies demonstrated that HIV replication and spreading mainly occur in lymphoid tissues, the identification of specific cell subsets harboring replication competent virus in lymphoid tissues has long been neglected. In this context, we and others have recently shown that gut memory CD4 T cells, lymph node T follicular helper (Tfh) cells and tissue macrophages represent major HIV/SIV tissue reservoirs. Notably, Tfh cell differentiation is a multi-stage process that requires long-lasting interactions with lymph node (LN) dendritic cells (DCs) and pre-germinal center B cells in a specific cytokine/chemokine microenvironment. Lymph node DCs are endowed with an exceptional T-cell stimulatory potential and can either migrate from the periphery to the draining lymph node (migratory DCs) or locate in the LN for their entire life span (resident DCs). On the basis of these unique properties, long-term persistence of LN DCs infected with replication competent virus may represent the initial trigger of viral rebound post ART interruption and may therefore represent a major obstacle to HIV cure. We demonstrate that LN migratory DCs are infected with replication competent virus and persist despite suppressive ART. In addition, we identified the mechanisms associated with i) LN DC susceptibility to HIV infection and ii) long term persistence of HIV-infected LN DCs i.e. proliferation of infected cells in tissue sanctuaries.
2023-09-13 | GSE196066 | GEO
Project description:A key mechanism of tumor resistance to immune cells is mediated by expression of peptide-loaded HLA-E in tumor cells, which suppresses natural killer (NK) cell activity via ligation of the NK inhibitory receptor CD94/NKG2A. To bypass HLA-E inhibition, we developed a way to generate highly functional NK cells lacking NKG2A. Constructs containing a single-chain variable fragment derived from an anti-NKG2A antibody were linked to endoplasmic reticulum-retention domains. After retroviral transduction in human peripheral blood NK cells, these NKG2A Protein Expression Blockers (PEBLs) abrogated NKG2A expression. The resulting NKG2Anull NK cells had higher cytotoxicity against HLA-E-expressing tumor cells.
2019-05-17 | GSE127081 | GEO
Project description:We studied the heterogeneity among human KIR/NKG2A+CD8+ T cells. First, we found that KIRs and NKG2A are expressed on human CD8+ T cells in a mutually exclusive manner. Therefore, we compared KIR+CD8+ and NKG2A+CD8+ T cells in regards to TCR overlap and transcriptomic profiles and demonstrated that KIR+CD8+ and NKG2A+CD8+ T cells are distinct innate-like populations.
2023-02-23 | GSE185567 | GEO
Project description:The goal of this project is todetermine if natural killer (NK) cells could be able to control HIV replication and reduce or eliminate viral reservoirs leading to HIV cure or a functional cure. Despite thirty years of work and significant progress, HIV infection continues to be an incurable disease. Antiretroviral therapy (ART) has significantly decreased the morbidity and mortality, but lifelong treatment is merely suppressive and does not cure HIV/AIDS. This is because of the existence of a reservoir of viral DNA+ (vDNA+) in cells of the lymphoid tissues with an intact provirus that is thought capable of initiating new rounds of HIV replication (i.e. latency). In addition to this inducible reservoir data suggest ongoing low-level virus replication and persistence in lymphatic tissues of some patients that is related to suboptimal drug levels in these tissues. Strategies are needed that can address both issues. NK cells are innate immune effectors that recognize virally infected targets through a cadre of activating and inhibitory receptors but become dysfunctional in HIV infected people. Strikingly, African green monkeys (AGM) and sooty mangabeys mount a strong control of viral replication in lymph node follicles shortly after the viremia peak that lasts throughout infection. Several mechanisms have been proposed to be implicated in the strong control of viral replication in natural host’s lymph nodes, such as NK cell-mediated control. Indeed, we have recently shown that NK cells could migrate into the b cells follicles in a CXCR5 dependent manner and thus participate to the elimination of viral replication. Thus the purpose of this study is too compare at the transcriptomic level different subset of NK cell isolated from blood and peripheral lymph node of chronically infected AGM to identify a transcriptomic signature which could be linked to an efficient control of SIV replication. This results could then provide a new aproche which could be exploited to generate functional NK cells against HIV in infected patients.
2020-12-21 | GSE140600 | GEO