ICOS-deficient Treg cells can prevent spontaneous autoimmunity but are impaired in controlling acute inflammation
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA768404 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:ICOS is induced in activated T cells and its main role is to boost differentiation and function of effector T cells. ICOS is also constitutively expressed in a subpopulation of Foxp3+ regulatory T cells under steady-state condition. Studies using ICOS germline knockout mice or ICOS-blocking reagents suggested that ICOS has supportive roles in regulatory T (Treg) cell homeostasis, migration, and function. To avoid any compounding effects that may arise from ICOS-deficient non-Treg cells, we generated a conditional knockout system in which ICOS expression is selectively abrogated in Foxp3-expressing cells (ICOS FC mice). Compared to Foxp3-Cre control mice, ICOS FC mice showed a minor numerical deficit of steady-state Treg cells but did not show any signs of spontaneous autoimmunity, indicating that tissue-protective Treg populations do not heavily rely on ICOS costimulation. However, ICOS FC mice showed more severe inflammation in oxazolone-induced contact hypersensitivity, a model of atopic dermatitis. This correlated with elevated numbers of inflammatory T cells expressing IFN-γ and/or TNF-α in ICOS FC mice compared with the control group. In contrast, elimination of ICOS in all T cell compartments negated the differences, confirming that ICOS has a dual positive role in effector and Treg cells. Single-cell transcriptome analysis suggested that ICOS-deficient Treg cells fail to mature into T-bet+CXCR3+ “Th1-Treg” cells in the draining lymph node. Our results suggest that regimens that preferentially stimulate ICOS pathways in Treg cells might be beneficial for the treatment of Th1-driven inflammation.
2022-07-08 | GSE185254 | GEO
Project description:Interaction of ICOS - ICOS ligand is required for the germinal center formation, T-cell immune responses, and development of autoimmune diseases. Human ICOS deficiency with the identical ICOS mutation has been identified in nine patients worldwide. In vitro studies showed T-cell defect of the patients was mild, and in vivo autoimmunity was uncommon and mild. Here we report in-depth analysis of T-cell function in two siblings with novel ICOS deficiency. While the brother displayed mild skin infections, psoriasis-like skin region, and defective immunoglobulin class switching, the sister had more severe symptoms, which included immunodeficiency, rheumatoid arthritis, inflammatory bowel disease, interstitial pneumonitis, and psoriasis. Despite of normal CD3/CD28-induced proliferation and IL-2 production in vitro, peripheral blood T-cells from both patients demonstrated decreased percentage of CD4 central and effector memory T-cells and impaired production of Th1, Th2, and Th17 cytokines upon CD3/CD28 costimulation or upon PMA/ionophore stimulation. The defective polarization into effector cells were associated with impaired induction of T-bet, GATA3 and MAF and RORC. Reduced CTLA-4+CD45RO+ FoxP3+ regulatory T-cells and diminished induction of inhibitory cell surface molecules including CTLA-4 were also observed in the patients. Further analysis of the gene expression and immune functions of the patients demonstrated increased induction of RANKL, lack of IFN-g response, and loss of Itch expression upon activation in the female case with autoimmunity. Our study suggests extensive T-cell dysfunction and loss of balance between effector cells and regulatory cells in the ICOS-deficient patients may account for their immunodeficiency and/or autoimmune disorder.
2008-09-26 | GSE12875 | GEO
Project description:The role of ICOS in anti-tumor T cell responses and overall tumor progression has been controversial. Here, we compared tumor progression in mice lacking ICOS only in Treg cells or in all T cells. We found that Treg-specific ICOS knockout reduces the overall tumor burden compared to Cre control mice with increased T effector/Treg ratios in the tumor. In contrast, there was no difference in the tumor burden in mice lacking ICOS in all the T cell compartments. This suggests a dual role of ICOS costimulation in promoting pro- and anti-tumor T cell responses. Consistent with reduced tumor burden, we found that Treg-specific deletion of ICOS leads to an increase of CD8+ CTLs that express high levels of granzyme B and perforin. Moreover, single-cell transcriptome analysis revealed an increase of Ly108hiEomeshi CD8+ T cell subset at the cost of Ly108hiT-bethi subset in Treg-specific knockout mice. These results suggest that ICOS-expressing Treg cells suppress CTL maturation process at the level of Eomes upregulation, a critical step known to drive perforin expression and cytotoxicity. Collectively, our data imply that cancer immunotherapies using ICOS agonist antibodies would work better in Treg-low tumors or when they are combined with regimens that deplete tumor-infiltrating Treg cells.
2024-07-18 | GSE226471 | GEO
Project description:Fine-mapping and functional studies implicate rs117701653, a common non-coding variant in the CD28/CTLA4/ICOS locus, as a contributor to risk for rheumatoid arthritis and type 1 diabetes. Using DNA pulldown, mass spectrometry, genome editing and eQTL analysis, we establish that the disease-associated allele reduces affinity for the inhibitory chromosomal regulator SMCHD1 to drive expression of inducible T-cell costimulator (ICOS), enhancing memory CD4+ T cell ICOS expression in individuals bearing the risk allele. Higher ICOS expression is paralleled by an increase in circulating T peripheral helper (Tph) cells, and in rheumatoid arthritis patients, of blood and joint fluid Tph cells and circulating plasmablasts, suggesting a causal link. Indeed, ICOS ligation accelerates T cell differentiation into CXCR5-PD-1high Tph cells producing IL-21 and CXCL13, as does carriage of the rs117701653 risk allele. Thus, mechanistic dissection of a causal non-coding variant in human autoimmunity discloses a new pathway through which ICOS regulates Tph abundance.
2023-07-01 | GSE235868 | GEO
Project description:ICOS (Inducible Costimulator) is a T cell costimulatory molecule. We found that the cloned T-cell hybridoma 6-13-64 consists of two populations, ICOS expressing and non-expressing. The aim of this study is to screen for candidate genes that regulate ICOS gene expression by transcriptional profiling and comparison of the ICOS-positive and ICOS-negative subpopulations isolated from the 6-13-64 T-cell hybridoma. One-condition experiment, ICOS(-) vs. ICOS(+) cells. Independently grown and harvested. One replicate per array.
2012-03-31 | E-GEOD-20922 | biostudies-arrayexpress
Project description:ICOS (Inducible Costimulator) is a T cell costimulatory molecule. We found that the cloned T-cell hybridoma 6-13-64 consists of two populations, ICOS expressing and non-expressing. The aim of this study is to screen for candidate genes that regulate ICOS gene expression by transcriptional profiling and comparison of the ICOS-positive and ICOS-negative subpopulations isolated from the 6-13-64 T-cell hybridoma.
2012-04-01 | GSE20922 | GEO
Project description:Inducible co-stimulator (ICOS) interaction with its ligand (ICOSL) is involved in several T cell effector functions. While blockade of ICOS:ICOSL interaction in chronic graft versus host disease (GVHD) seems benefi cial, results for acute GVHD remain controversial. To further elucidate its role in acute GVHD, C57BL / 6 mice were lethally irradiated and reconstituted with allogeneic spleen cells in the absence or presence of ICOSL-blocking mAb. Mice reconstituted with allogeneic spleen cells experienced severe GVHD and died untreated within 6 – 9 days after transplantation. Mice treated with an anti-ICOSL mAb starting from day 3 after transplantation gained weight again and survived for at least additional 12 days, although the treatment was already stopped at day 11 after transplantation. In contrast, the anti-ICOSL treatment starting from day 0 did not prevent GVHD. The diff erence between therapeutic (day 3) and prophylactic (day 0) anti-ICOSL treatment was independent of CD25 + CD4 + regulatory T cells since their depletion did not abrogate the therapeutic eff ect of ICOSL blockade. Microarray analysis revealed IFN- γ and chemokine up-regulation in spleen cells of prophylactically treated mice, emphasizing kinetic dependence of acute GVHD modulation via blockade of ICOS:ICOSL interaction.
2009-09-14 | GSE17995 | GEO
Project description:Regulatory T (Treg) cells are critical in preventing aberrant immune responses. Posttranscriptional control of gene expression by microRNA (miRNA) has recently emerged as an essential genetic element for Treg cell function. Here, we report that mice with Treg cell-specific ablation of miR-142 (hereafter Foxp3CremiR-142fl/fl mice) developed a fatal systemic autoimmune disorder due to a breakdown in peripheral T-cell tolerance. Foxp3CremiR-142fl/fl mice displayed a significant decrease in the abundance and suppressive capacity of Treg cells. Expression profiling of miR-142-deficient Treg cells revealed an up-regulation of multiple genes in the interferon gamma (IFNγ) signaling network. We identified several of these IFNγ-associated genes as direct miR-142-3p targets and observed excessive IFNγ production and signaling in miR-142-deficient Treg cells. Ifng ablation rescued the Treg cell homeostatic defect and alleviated development of autoimmunity in Foxp3CremiR-142fl/fl mice. Thus, our findings implicate miR-142 as an indispensable regulator of Treg cell homeostasis that exerts its function by attenuating IFNγ responses.
| S-EPMC8893712 | biostudies-literature
Project description:Regulatory T (Treg) cells expressing the transcription factor Foxp3 have a pivotal role in maintaining immunological self-tolerance; yet, excessive Treg cell activities suppress anti-tumour immune responses. Compared to the resting Treg (rTreg) cell phenotype in secondary lymphoid organs, Treg cells in non-lymphoid tissues exhibit an activated Treg (aTreg) cell phenotype. However, the function of aTreg cells and whether their generation can be manipulated are largely unexplored. Here we show that the transcription factor Foxo1, previously demonstrated to promote Treg cell suppression of lymphoproliferative diseases, has an unexpected function in inhibiting aTreg-cell-mediated immune tolerance in mice. We find that aTreg cells turned over at a slower rate than rTreg cells, but were not locally maintained in tissues. aTreg cell differentiation was associated with repression of Foxo1-dependent gene transcription, concomitant with reduced Foxo1 expression, cytoplasmic localization and enhanced phosphorylation at the Akt sites. Treg-cell-specific expression of an Akt-insensitive Foxo1 mutant prevented downregulation of lymphoid organ homing molecules, and impeded Treg cell homing to non-lymphoid organs, causing CD8(+) T-cell-mediated autoimmune diseases. Compared to Treg cells from healthy tissues, tumour-infiltrating Treg cells downregulated Foxo1 target genes more substantially. Expression of the Foxo1 mutant at a lower dose was sufficient to deplete tumour-associated Treg cells, activate effector CD8(+) T cells, and inhibit tumour growth without inflicting autoimmunity. Thus, Foxo1 inactivation is essential for the migration of aTreg cells that have a crucial function in suppressing CD8(+) T-cell responses; and the Foxo signalling pathway in Treg cells can be titrated to break tumour immune tolerance preferentially.
| S-EPMC4978705 | biostudies-literature
Project description:ICOS is a T cell costimulatory receptor critical for Tfh cell generation and function. However, the role of ICOS in Tfr cell differentiation remains unclear. Using Foxp3-Cre-mediated ICOS knockout (ICOS FC) mice, we show that ICOS deficiency in Treg-lineage cells drastically reduces the number of Tfr cells during GC reactions but has a minimal impact on conventional Treg cells. Single-cell transcriptome analysis of Foxp3+ cells at an early stage of the GC reaction suggests that ICOS normally inhibits Klf2 expression to promote follicular features including Bcl6 upregulation. Further, ICOS costimulation promotes nuclear localization of NFAT2, a known driver of CXCR5 expression. Notably, ICOS FC mice had an unaltered overall GC B cell output but showed signs of expanded autoreactive B cells along with elevated autoantibody titers. Thus, our study demonstrates that ICOS costimulation is critical for Tfr cell differentiation and highlights the importance of Tfr cells in maintaining humoral immune tolerance during GC reactions.
2023-02-02 | GSE164995 | GEO