RESUMO
Clinical trials have identified ARID1A mutations as enriched among patients who respond favorably to immune checkpoint blockade (ICB) in several solid tumor types independent of microsatellite instability. We show that ARID1A loss in murine models is sufficient to induce anti-tumor immune phenotypes observed in ARID1A mutant human cancers, including increased CD8+ T cell infiltration and cytolytic activity. ARID1A-deficient cancers upregulated an interferon (IFN) gene expression signature, the ARID1A-IFN signature, associated with increased R-loops and cytosolic single-stranded DNA (ssDNA). Overexpression of the R-loop resolving enzyme, RNASEH2B, or cytosolic DNase, TREX1, in ARID1A-deficient cells prevented cytosolic ssDNA accumulation and ARID1A-IFN gene upregulation. Further, the ARID1A-IFN signature and anti-tumor immunity were driven by STING-dependent type I IFN signaling, which was required for improved responsiveness of ARID1A mutant tumors to ICB treatment. These findings define a molecular mechanism underlying anti-tumor immunity in ARID1A mutant cancers.
Assuntos
Linfócitos T CD8-Positivos , Proteínas de Ligação a DNA , Interferon Tipo I , Proteínas de Membrana , Neoplasias , Transdução de Sinais , Fatores de Transcrição , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Exodesoxirribonucleases/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Interferon Tipo I/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Mutação , Neoplasias/imunologia , Neoplasias/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Masculino , Quimiocinas/genética , Quimiocinas/metabolismoRESUMO
Overcoming immune-mediated resistance to PD-1 blockade remains a major clinical challenge. Enhanced efficacy has been demonstrated in melanoma patients with combined nivolumab (anti-PD-1) and relatlimab (anti-LAG-3) treatment, the first in its class to be FDA approved. However, how these two inhibitory receptors synergize to hinder anti-tumor immunity remains unknown. Here, we show that CD8+ T cells deficient in both PD-1 and LAG-3, in contrast to CD8+ T cells lacking either receptor, mediate enhanced tumor clearance and long-term survival in mouse models of melanoma. PD-1- and LAG-3-deficient CD8+ T cells were transcriptionally distinct, with broad TCR clonality and enrichment of effector-like and interferon-responsive genes, resulting in enhanced IFN-γ release indicative of functionality. LAG-3 and PD-1 combined to drive T cell exhaustion, playing a dominant role in modulating TOX expression. Mechanistically, autocrine, cell-intrinsic IFN-γ signaling was required for PD-1- and LAG-3-deficient CD8+ T cells to enhance anti-tumor immunity, providing insight into how combinatorial targeting of LAG-3 and PD-1 enhances efficacy.
Assuntos
Antígenos CD , Linfócitos T CD8-Positivos , Interferon gama , Proteína do Gene 3 de Ativação de Linfócitos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1 , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Animais , Interferon gama/metabolismo , Camundongos , Antígenos CD/metabolismo , Comunicação Autócrina , Humanos , Melanoma/imunologia , Melanoma/tratamento farmacológico , Feminino , Linhagem Celular Tumoral , Melanoma Experimental/imunologia , Exaustão das Células TRESUMO
Chimeric antigen receptor (CAR) T cell therapy effectively treats human cancer, but the loss of the antigen recognized by the CAR poses a major obstacle. We found that in vivo vaccine boosting of CAR T cells triggers the engagement of the endogenous immune system to circumvent antigen-negative tumor escape. Vaccine-boosted CAR T promoted dendritic cell (DC) recruitment to tumors, increased tumor antigen uptake by DCs, and elicited the priming of endogenous anti-tumor T cells. This process was accompanied by shifts in CAR T metabolism toward oxidative phosphorylation (OXPHOS) and was critically dependent on CAR-T-derived IFN-γ. Antigen spreading (AS) induced by vaccine-boosted CAR T enabled a proportion of complete responses even when the initial tumor was 50% CAR antigen negative, and heterogeneous tumor control was further enhanced by the genetic amplification of CAR T IFN-γ expression. Thus, CAR-T-cell-derived IFN-γ plays a critical role in promoting AS, and vaccine boosting provides a clinically translatable strategy to drive such responses against solid tumors.
Assuntos
Vacinas Anticâncer , Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Neoplasias/terapia , Linfócitos T , Imunoterapia Adotiva , Receptores de Antígenos de Linfócitos T/metabolismoRESUMO
Patients with autoinflammatory diseases present with noninfectious fever flares and systemic and/or disease-specific organ inflammation. Their excessive proinflammatory cytokine and chemokine responses can be life threatening and lead to organ damage over time. Studying such patients has revealed genetic defects that have helped unravel key innate immune pathways, including excessive IL-1 signaling, constitutive NF-κB activation, and, more recently, chronic type I IFN signaling. Discoveries of monogenic defects that lead to activation of proinflammatory cytokines have inspired the use of anticytokine-directed treatment approaches that have been life changing for many patients and have led to the approval of IL-1-blocking agents for a number of autoinflammatory conditions. In this review, we describe the genetically characterized autoinflammatory diseases, we summarize our understanding of the molecular pathways that drive clinical phenotypes and that continue to inspire the search for novel treatment targets, and we provide a conceptual framework for classification.
Assuntos
Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Predisposição Genética para Doença , Inflamação/genética , Inflamação/imunologia , Animais , Doenças Autoimunes/metabolismo , Autoimunidade , Modelos Animais de Doenças , Humanos , Imunidade Inata , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/metabolismo , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Interferons/metabolismo , Interleucina-1/metabolismo , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , NF-kappa B/metabolismo , Transdução de SinaisRESUMO
Severe coronavirus disease 2019 (COVID-19) is characterized by overproduction of immune mediators, but the role of interferons (IFNs) of the type I (IFN-I) or type III (IFN-III) families remains debated. We scrutinized the production of IFNs along the respiratory tract of COVID-19 patients and found that high levels of IFN-III, and to a lesser extent IFN-I, characterize the upper airways of patients with high viral burden but reduced disease risk or severity. Production of specific IFN-III, but not IFN-I, members denotes patients with a mild pathology and efficiently drives the transcription of genes that protect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In contrast, compared to subjects with other infectious or noninfectious lung pathologies, IFNs are overrepresented in the lower airways of patients with severe COVID-19 that exhibit gene pathways associated with increased apoptosis and decreased proliferation. Our data demonstrate a dynamic production of IFNs in SARS-CoV-2-infected patients and show IFNs play opposing roles at distinct anatomical sites.
Assuntos
COVID-19/patologia , Interferons/metabolismo , Sistema Respiratório/virologia , Índice de Gravidade de Doença , Fatores Etários , Envelhecimento/patologia , COVID-19/genética , COVID-19/imunologia , Células Epiteliais/patologia , Células Epiteliais/virologia , Regulação da Expressão Gênica , Humanos , Interferons/genética , Leucócitos/patologia , Leucócitos/virologia , Pulmão/patologia , Pulmão/virologia , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/virologia , Carga ViralRESUMO
COVID-19 is characterized by excessive production of pro-inflammatory cytokines and acute lung damage associated with patient mortality. While multiple inflammatory cytokines are produced by innate immune cells during SARS-CoV-2 infection, we found that only the combination of TNF-α and IFN-γ induced inflammatory cell death characterized by inflammatory cell death, PANoptosis. Mechanistically, TNF-α and IFN-γ co-treatment activated the JAK/STAT1/IRF1 axis, inducing nitric oxide production and driving caspase-8/FADD-mediated PANoptosis. TNF-α and IFN-γ caused a lethal cytokine shock in mice that mirrors the tissue damage and inflammation of COVID-19, and inhibiting PANoptosis protected mice from this pathology and death. Furthermore, treating with neutralizing antibodies against TNF-α and IFN-γ protected mice from mortality during SARS-CoV-2 infection, sepsis, hemophagocytic lymphohistiocytosis, and cytokine shock. Collectively, our findings suggest that blocking the cytokine-mediated inflammatory cell death signaling pathway identified here may benefit patients with COVID-19 or other infectious and autoinflammatory diseases by limiting tissue damage/inflammation.
Assuntos
COVID-19/imunologia , COVID-19/patologia , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/patologia , Interferon gama/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Morte Celular , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/imunologia , Inflamação/patologia , Linfo-Histiocitose Hemofagocítica/induzido quimicamente , Masculino , Camundongos , Camundongos Transgênicos , Células THP-1RESUMO
Cytoplasmic accumulation of TDP-43 is a disease hallmark for many cases of amyotrophic lateral sclerosis (ALS), associated with a neuroinflammatory cytokine profile related to upregulation of nuclear factor κB (NF-κB) and type I interferon (IFN) pathways. Here we show that this inflammation is driven by the cytoplasmic DNA sensor cyclic guanosine monophosphate (GMP)-AMP synthase (cGAS) when TDP-43 invades mitochondria and releases DNA via the permeability transition pore. Pharmacologic inhibition or genetic deletion of cGAS and its downstream signaling partner STING prevents upregulation of NF-κB and type I IFN induced by TDP-43 in induced pluripotent stem cell (iPSC)-derived motor neurons and in TDP-43 mutant mice. Finally, we document elevated levels of the specific cGAS signaling metabolite cGAMP in spinal cord samples from patients, which may be a biomarker of mtDNA release and cGAS/STING activation in ALS. Our results identify mtDNA release and cGAS/STING activation as critical determinants of TDP-43-associated pathology and demonstrate the potential for targeting this pathway in ALS.
Assuntos
Esclerose Lateral Amiotrófica/metabolismo , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Membrana/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Nucleotidiltransferases/metabolismo , Alarminas/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Citoplasma/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Inflamação/metabolismo , Interferon Tipo I/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Degeneração Neural/patologia , Fosfotransferases (Aceptor do Grupo Álcool) , Subunidades Proteicas/metabolismo , Transdução de SinaisRESUMO
A greater understanding of hematopoietic stem cell (HSC) regulation is required for dissecting protective versus detrimental immunity to pathogens that cause chronic infections such as Mycobacterium tuberculosis (Mtb). We have shown that systemic administration of Bacille Calmette-Guérin (BCG) or ß-glucan reprograms HSCs in the bone marrow (BM) via a type II interferon (IFN-II) or interleukin-1 (IL1) response, respectively, which confers protective trained immunity against Mtb. Here, we demonstrate that, unlike BCG or ß-glucan, Mtb reprograms HSCs via an IFN-I response that suppresses myelopoiesis and impairs development of protective trained immunity to Mtb. Mechanistically, IFN-I signaling dysregulates iron metabolism, depolarizes mitochondrial membrane potential, and induces cell death specifically in myeloid progenitors. Additionally, activation of the IFN-I/iron axis in HSCs impairs trained immunity to Mtb infection. These results identify an unanticipated immune evasion strategy of Mtb in the BM that controls the magnitude and intrinsic anti-microbial capacity of innate immunity to infection.
Assuntos
Células-Tronco Hematopoéticas/microbiologia , Imunidade , Mycobacterium tuberculosis/fisiologia , Mielopoese , Animais , Células da Medula Óssea/metabolismo , Proliferação de Células , Suscetibilidade a Doenças , Homeostase , Interferon Tipo I/metabolismo , Ferro/metabolismo , Cinética , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , Necrose , Transdução de Sinais , Transcrição Gênica , Tuberculose/imunologia , Tuberculose/microbiologia , Tuberculose/patologiaRESUMO
The COVID-19 pandemic has led to extensive morbidity and mortality throughout the world. Clinical features that drive SARS-CoV-2 pathogenesis in humans include inflammation and thrombosis, but the mechanistic details underlying these processes remain to be determined. In this study, we demonstrate endothelial disruption and vascular thrombosis in histopathologic sections of lungs from both humans and rhesus macaques infected with SARS-CoV-2. To define key molecular pathways associated with SARS-CoV-2 pathogenesis in macaques, we performed transcriptomic analyses of bronchoalveolar lavage and peripheral blood and proteomic analyses of serum. We observed macrophage infiltrates in lung and upregulation of macrophage, complement, platelet activation, thrombosis, and proinflammatory markers, including C-reactive protein, MX1, IL-6, IL-1, IL-8, TNFα, and NF-κB. These results suggest a model in which critical interactions between inflammatory and thrombosis pathways lead to SARS-CoV-2-induced vascular disease. Our findings suggest potential therapeutic targets for COVID-19.
Assuntos
COVID-19/complicações , COVID-19/imunologia , SARS-CoV-2/genética , Trombose/complicações , Doenças Vasculares/complicações , Idoso de 80 Anos ou mais , Animais , Lavagem Broncoalveolar , Proteína C-Reativa/análise , COVID-19/sangue , COVID-19/patologia , Ativação do Complemento , Citocinas/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/imunologia , Inflamação/virologia , Pulmão/patologia , Macaca mulatta , Macrófagos/imunologia , Masculino , Ativação Plaquetária , Trombose/sangue , Trombose/patologia , Transcriptoma , Doenças Vasculares/sangue , Doenças Vasculares/patologiaRESUMO
Inborn errors of human interferon gamma (IFN-γ) immunity underlie mycobacterial disease. We report a patient with mycobacterial disease due to inherited deficiency of the transcription factor T-bet. The patient has extremely low counts of circulating Mycobacterium-reactive natural killer (NK), invariant NKT (iNKT), mucosal-associated invariant T (MAIT), and Vδ2+ γδ T lymphocytes, and of Mycobacterium-non reactive classic TH1 lymphocytes, with the residual populations of these cells also producing abnormally small amounts of IFN-γ. Other lymphocyte subsets develop normally but produce low levels of IFN-γ, with the exception of CD8+ αß T and non-classic CD4+ αß TH1∗ lymphocytes, which produce IFN-γ normally in response to mycobacterial antigens. Human T-bet deficiency thus underlies mycobacterial disease by preventing the development of innate (NK) and innate-like adaptive lymphocytes (iNKT, MAIT, and Vδ2+ γδ T cells) and IFN-γ production by them, with mycobacterium-specific, IFN-γ-producing, purely adaptive CD8+ αß T, and CD4+ αß TH1∗ cells unable to compensate for this deficit.
Assuntos
Imunidade Adaptativa , Imunidade Inata , Interferon gama/imunologia , Mycobacterium/imunologia , Proteínas com Domínio T/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Linhagem da Célula , Pré-Escolar , Cromatina/metabolismo , Ilhas de CpG/genética , Metilação de DNA/genética , Células Dendríticas/metabolismo , Epigênese Genética , Feminino , Homozigoto , Humanos , Mutação INDEL/genética , Lactente , Interferon gama/metabolismo , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Mutação com Perda de Função/genética , Masculino , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/microbiologia , Linhagem , Proteínas com Domínio T/química , Proteínas com Domínio T/deficiência , Proteínas com Domínio T/genética , Linfócitos T Auxiliares-Indutores/imunologia , Transcriptoma/genéticaRESUMO
Memory B cells (MBCs) are key providers of long-lived immunity against infectious disease, yet in chronic viral infection, they do not produce effective protection. How chronic viral infection disrupts MBC development and whether such changes are reversible remain unknown. Through single-cell (sc)ATAC-seq and scRNA-seq during acute versus chronic lymphocytic choriomeningitis viral infection, we identified a memory subset enriched for interferon (IFN)-stimulated genes (ISGs) during chronic infection that was distinct from the T-bet+ subset normally associated with chronic infection. Blockade of IFNAR-1 early in infection transformed the chromatin landscape of chronic MBCs, decreasing accessibility at ISG-inducing transcription factor binding motifs and inducing phenotypic changes in the dominating MBC subset, with a decrease in the ISG subset and an increase in CD11c+CD80+ cells. However, timing was critical, with MBCs resistant to intervention at 4 weeks post-infection. Together, our research identifies a key mechanism to instruct MBC identity during viral infection.
Assuntos
Epigênese Genética , Interferon Tipo I , Coriomeningite Linfocítica , Vírus da Coriomeningite Linfocítica , Células B de Memória , Animais , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Camundongos , Vírus da Coriomeningite Linfocítica/imunologia , Células B de Memória/imunologia , Camundongos Endogâmicos C57BL , Receptor de Interferon alfa e beta/genética , Memória Imunológica/imunologia , Doença Crônica , Subpopulações de Linfócitos B/imunologia , Análise de Célula ÚnicaRESUMO
As a critical step during innate response, the cytoplasmic ß subunit (IFN-γR2) of interferon-γ receptor (IFN-γR) is induced and translocates to plasma membrane to join α subunit to form functional IFN-γR to mediate IFN-γ signaling. However, the mechanism driving membrane translocation and its significance remain largely unknown. We found, unexpectedly, that mice deficient in E-selectin, an endothelial cell-specific adhesion molecule, displayed impaired innate activation of macrophages upon Listeria monocytogenes infection yet had increased circulating IFN-γ. Inflammatory macrophages from E-selectin-deficient mice had less surface IFN-γR2 and impaired IFN-γ signaling. BTK elicited by extrinsic E-selectin engagement phosphorylates cytoplasmic IFN-γR2, facilitating EFhd2 binding and promoting IFN-γR2 trafficking from Golgi to cell membrane. Our findings demonstrate that membrane translocation of cytoplasmic IFN-γR2 is required to activate macrophage innate response against intracellular bacterial infection, identifying the assembly of functional cytokine receptors on cell membrane as an important layer in innate activation and cytokine signaling.
Assuntos
Selectina E/metabolismo , Imunidade Inata , Receptores de Interferon/metabolismo , Animais , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Membrana Celular/metabolismo , Selectina E/deficiência , Selectina E/genética , Complexo de Golgi/metabolismo , Interferon gama/sangue , Interferon gama/metabolismo , Listeria/patogenicidade , Ativação de Macrófagos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Transporte Proteico , Células RAW 264.7 , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Transdução de Sinais , Receptor de Interferon gamaRESUMO
Innate immune memory is an emerging area of research. However, innate immune memory at major mucosal sites remains poorly understood. Here, we show that respiratory viral infection induces long-lasting memory alveolar macrophages (AMs). Memory AMs are programed to express high MHC II, a defense-ready gene signature, and increased glycolytic metabolism, and produce, upon re-stimulation, neutrophil chemokines. Using a multitude of approaches, we reveal that the priming, but not maintenance, of memory AMs requires the help from effector CD8 T cells. T cells jump-start this process via IFN-γ production. We further find that formation and maintenance of memory AMs are independent of monocytes or bone marrow progenitors. Finally, we demonstrate that memory AMs are poised for robust trained immunity against bacterial infection in the lung via rapid induction of chemokines and neutrophilia. Our study thus establishes a new paradigm of immunological memory formation whereby adaptive T-lymphocytes render innate memory of mucosal-associated macrophages.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunidade Inata , Pulmão/imunologia , Macrófagos Alveolares/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Linfócitos T CD8-Positivos/citologia , Memória Imunológica , Pulmão/citologia , Macrófagos Alveolares/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Monócitos/citologia , Monócitos/imunologia , Mucosa Respiratória/citologia , Mucosa Respiratória/imunologia , Linfócitos T Auxiliares-Indutores/citologiaRESUMO
Tumor-infiltrating CD8 T cells were found to frequently express the inhibitory receptor NKG2A, particularly in immune-reactive environments and after therapeutic cancer vaccination. High-dimensional cluster analysis demonstrated that NKG2A marks a unique immune effector subset preferentially co-expressing the tissue-resident CD103 molecule, but not immune checkpoint inhibitors. To examine whether NKG2A represented an adaptive resistance mechanism to cancer vaccination, we blocked the receptor with an antibody and knocked out its ligand Qa-1b, the conserved ortholog of HLA-E, in four mouse tumor models. The impact of therapeutic vaccines was greatly potentiated by disruption of the NKG2A/Qa-1b axis even in a PD-1 refractory mouse model. NKG2A blockade therapy operated through CD8 T cells, but not NK cells. These findings indicate that NKG2A-blocking antibodies might improve clinical responses to therapeutic cancer vaccines.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer , Imunidade Celular , Subfamília C de Receptores Semelhantes a Lectina de Células NK , Proteínas de Neoplasias , Neoplasias Experimentais , Vacinação , Animais , Anticorpos Antineoplásicos/imunologia , Antígenos CD/imunologia , Linfócitos T CD8-Positivos/patologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Cadeias alfa de Integrinas/imunologia , Camundongos , Subfamília C de Receptores Semelhantes a Lectina de Células NK/antagonistas & inibidores , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/imunologia , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Antígenos HLA-ERESUMO
Interferon-γ (IFN-γ) is a key cytokine in response to viral or intracellular bacterial infection in mammals. While a number of enhancers are described to promote IFN-γ responses, to the best of our knowledge, no silencers for the Ifng gene have been identified. By examining H3K4me1 histone modification in naive CD4+ T cells within Ifng locus, we identified a silencer (CNS-28) that restrains Ifng expression. Mechanistically, CNS-28 maintains Ifng silence by diminishing enhancer-promoter interactions within Ifng locus in a GATA3-dependent but T-bet-independent manner. Functionally, CNS-28 restrains Ifng transcription in NK cells, CD4+ cells, and CD8+ T cells during both innate and adaptive immune responses. Moreover, CNS-28 deficiency resulted in repressed type 2 responses due to elevated IFN-γ expression, shifting Th1 and Th2 paradigm. Thus, CNS-28 activity ensures immune cell quiescence by cooperating with other regulatory cis elements within the Ifng gene locus to minimize autoimmunity.
Assuntos
Linfócitos T CD8-Positivos , Interferon gama , Animais , Interferon gama/genética , Interferon gama/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Sequências Reguladoras de Ácido Nucleico , Homeostase , Células Th1 , MamíferosRESUMO
Arginase 1 (Arg1), the enzyme catalyzing the conversion of arginine to ornithine, is a hallmark of IL-10-producing immunoregulatory M2 macrophages. However, its expression in T cells is disputed. Here, we demonstrate that induction of Arg1 expression is a key feature of lung CD4+ T cells during mouse in vivo influenza infection. Conditional ablation of Arg1 in CD4+ T cells accelerated both virus-specific T helper 1 (Th1) effector responses and its resolution, resulting in efficient viral clearance and reduced lung pathology. Using unbiased transcriptomics and metabolomics, we found that Arg1-deficiency was distinct from Arg2-deficiency and caused altered glutamine metabolism. Rebalancing this perturbed glutamine flux normalized the cellular Th1 response. CD4+ T cells from rare ARG1-deficient patients or CRISPR-Cas9-mediated ARG1-deletion in healthy donor cells phenocopied the murine cellular phenotype. Collectively, CD4+ T cell-intrinsic Arg1 functions as an unexpected rheostat regulating the kinetics of the mammalian Th1 lifecycle with implications for Th1-associated tissue pathologies.
Assuntos
Arginase , Influenza Humana , Animais , Humanos , Camundongos , Arginase/genética , Arginase/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Glutamina , Cinética , Pulmão/metabolismo , MamíferosRESUMO
Down syndrome (DS) is typically caused by triplication of chromosome 21. Phenotypically, DS presents with developmental, neurocognitive, and immune features. Epidemiologically, individuals with DS have less frequent viral infection, but when present, these infections lead to more severe disease. The potent antiviral cytokine type I Interferon (IFN-I) receptor subunits IFNAR1 and IFNAR2 are located on chromosome 21. While increased IFNAR1/2 expression initially caused hypersensitivity to IFN-I, it triggered excessive negative feedback. This led to a hypo-response to subsequent IFN-I stimuli and an ensuing viral susceptibility in DS compared to control cells. Upregulation of IFNAR2 expression phenocopied the DS IFN-I dynamics independent of trisomy 21. CD14+ monocytes from individuals with DS exhibited markers of prior IFN-I exposure and had muted responsiveness to ex vivo IFN-I stimulation. Our findings unveil oscillations of hyper- and hypo-response to IFN-I in DS, predisposing individuals to both lower incidence of viral disease and increased infection-related morbidity and mortality.
Assuntos
Síndrome de Down , Interferon Tipo I , Humanos , Interferon Tipo I/metabolismo , Síndrome de Down/genética , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Antivirais , Suscetibilidade a Doenças , Receptores de Interferon/metabolismoRESUMO
Antibody blockade of the inhibitory CTLA-4 pathway has led to clinical benefit in a subset of patients with metastatic melanoma. Anti-CTLA-4 enhances T cell responses, including production of IFN-γ, which is a critical cytokine for host immune responses. However, the role of IFN-γ signaling in tumor cells in the setting of anti-CTLA-4 therapy remains unknown. Here, we demonstrate that patients identified as non-responders to anti-CTLA-4 (ipilimumab) have tumors with genomic defects in IFN-γ pathway genes. Furthermore, mice bearing melanoma tumors with knockdown of IFN-γ receptor 1 (IFNGR1) have impaired tumor rejection upon anti-CTLA-4 therapy. These data highlight that loss of the IFN-γ signaling pathway is associated with primary resistance to anti-CTLA-4 therapy. Our findings demonstrate the importance of tumor genomic data, especially IFN-γ related genes, as prognostic information for patients selected to receive treatment with immune checkpoint therapy.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/genética , Interferon gama/genética , Melanoma/tratamento farmacológico , Receptores de Interferon/genética , Neoplasias Cutâneas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Citocinas/imunologia , Técnicas de Silenciamento de Genes , Humanos , Ipilimumab , Melanoma/genética , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/genética , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Cutâneas/genética , Linfócitos T/imunologia , Receptor de Interferon gamaRESUMO
Longitudinal analyses of the innate immune system, including the earliest time points, are essential to understand the immunopathogenesis and clinical course of coronavirus disease (COVID-19). Here, we performed a detailed characterization of natural killer (NK) cells in 205 patients (403 samples; days 2 to 41 after symptom onset) from four independent cohorts using single-cell transcriptomics and proteomics together with functional studies. We found elevated interferon (IFN)-α plasma levels in early severe COVD-19 alongside increased NK cell expression of IFN-stimulated genes (ISGs) and genes involved in IFN-α signaling, while upregulation of tumor necrosis factor (TNF)-induced genes was observed in moderate diseases. NK cells exert anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) activity but are functionally impaired in severe COVID-19. Further, NK cell dysfunction may be relevant for the development of fibrotic lung disease in severe COVID-19, as NK cells exhibited impaired anti-fibrotic activity. Our study indicates preferential IFN-α and TNF responses in severe and moderate COVID-19, respectively, and associates a prolonged IFN-α-induced NK cell response with poorer disease outcome.
Assuntos
COVID-19/imunologia , Interferon-alfa/imunologia , Células Matadoras Naturais/imunologia , SARS-CoV-2/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Sequência de Bases , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interferon-alfa/sangue , Fibrose Pulmonar/patologia , RNA-Seq , Índice de Gravidade de Doença , Transcriptoma/genética , Reino Unido , Estados UnidosRESUMO
The emergence and spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in significant global morbidity, mortality, and societal disruption. A better understanding of virus-host interactions may potentiate therapeutic insights toward limiting this infection. Here we investigated the dynamics of the systemic response to SARS-CoV-2 in hamsters by histological analysis and transcriptional profiling. Infection resulted in consistently high levels of virus in the upper and lower respiratory tracts and sporadic occurrence in other distal tissues. A longitudinal cohort revealed a wave of inflammation, including a type I interferon (IFN-I) response, that was evident in all tissues regardless of viral presence but was insufficient to prevent disease progression. Bolstering the antiviral response with intranasal administration of recombinant IFN-I reduced viral disease, prevented transmission, and lowered inflammation in vivo. This study defines the systemic host response to SARS-CoV-2 infection and supports use of intranasal IFN-I as an effective means of early treatment.