RESUMO
Respiratory infections cause significant morbidity and mortality, yet it is unclear why some individuals succumb to severe disease. In patients hospitalized with avian A(H7N9) influenza, we investigated early drivers underpinning fatal disease. Transcriptomics strongly linked oleoyl-acyl-carrier-protein (ACP) hydrolase (OLAH), an enzyme mediating fatty acid production, with fatal A(H7N9) early after hospital admission, persisting until death. Recovered patients had low OLAH expression throughout hospitalization. High OLAH levels were also detected in patients hospitalized with life-threatening seasonal influenza, COVID-19, respiratory syncytial virus (RSV), and multisystem inflammatory syndrome in children (MIS-C) but not during mild disease. In olah-/- mice, lethal influenza infection led to survival and mild disease as well as reduced lung viral loads, tissue damage, infection-driven pulmonary cell infiltration, and inflammation. This was underpinned by differential lipid droplet dynamics as well as reduced viral replication and virus-induced inflammation in macrophages. Supplementation of oleic acid, the main product of OLAH, increased influenza replication in macrophages and their inflammatory potential. Our findings define how the expression of OLAH drives life-threatening viral disease.
RESUMO
SARS-CoV-2 mRNA vaccines induce robust anti-spike (S) antibody and CD4+ T cell responses. It is not yet clear whether vaccine-induced follicular helper CD4+ T (TFH) cell responses contribute to this outstanding immunogenicity. Using fine-needle aspiration of draining axillary lymph nodes from individuals who received the BNT162b2 mRNA vaccine, we evaluated the T cell receptor sequences and phenotype of lymph node TFH. Mining of the responding TFH T cell receptor repertoire revealed a strikingly immunodominant HLA-DPB1∗04-restricted response to S167-180 in individuals with this allele, which is among the most common HLA alleles in humans. Paired blood and lymph node specimens show that while circulating S-specific TFH cells peak one week after the second immunization, S-specific TFH persist at nearly constant frequencies for at least six months. Collectively, our results underscore the key role that robust TFH cell responses play in establishing long-term immunity by this efficacious human vaccine.
Assuntos
COVID-19/imunologia , COVID-19/virologia , Imunidade/imunologia , SARS-CoV-2/imunologia , Células T Auxiliares Foliculares/imunologia , Vacinação , Vacinas Sintéticas/imunologia , Vacinas de mRNA/imunologia , Adulto , Linfócitos B/imunologia , Vacina BNT162/imunologia , COVID-19/sangue , Células Clonais , Estudos de Coortes , Citocinas/metabolismo , Feminino , Centro Germinativo/imunologia , Cadeias beta de HLA-DP/imunologia , Humanos , Epitopos Imunodominantes/imunologia , Células Jurkat , Linfonodos/metabolismo , Masculino , Pessoa de Meia-Idade , Peptídeos/química , Peptídeos/metabolismo , Multimerização Proteica , Receptores de Antígenos de Linfócitos T/metabolismoRESUMO
CD8+ T cells provide robust antiviral immunity, but how epitope-specific T cells evolve across the human lifespan is unclear. Here we defined CD8+ T cell immunity directed at the prominent influenza epitope HLA-A*02:01-M158-66 (A2/M158) across four age groups at phenotypic, transcriptomic, clonal and functional levels. We identify a linear differentiation trajectory from newborns to children then adults, followed by divergence and a clonal reset in older adults. Gene profiles in older adults closely resemble those of newborns and children, despite being clonally distinct. Only child-derived and adult-derived A2/M158+CD8+ T cells had the potential to differentiate into highly cytotoxic epitope-specific CD8+ T cells, which was linked to highly functional public T cell receptor (TCR)αß signatures. Suboptimal TCRαß signatures in older adults led to less proliferation, polyfunctionality, avidity and recognition of peptide mutants, although displayed no signs of exhaustion. These data suggest that priming T cells at different stages of life might greatly affect CD8+ T cell responses toward viral infections.
Assuntos
Linfócitos T CD8-Positivos , Longevidade , Recém-Nascido , Humanos , Idoso , Epitopos de Linfócito T/genética , Linfócitos T Citotóxicos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T/genéticaRESUMO
High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4+ and CD8+ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacina BNT162 , COVID-19/prevenção & controle , Linfócitos T CD8-Positivos , Austrália/epidemiologia , SARS-CoV-2 , Imunoglobulina G , Anticorpos Neutralizantes , Imunidade , Anticorpos Antivirais , VacinaçãoRESUMO
Influenza A virus (IAV) is a lytic RNA virus that triggers receptor-interacting serine/threonine-protein kinase 3 (RIPK3)-mediated pathways of apoptosis and mixed lineage kinase domain-like pseudokinase (MLKL)-dependent necroptosis in infected cells. ZBP1 initiates RIPK3-driven cell death by sensing IAV RNA and activating RIPK3. Here, we show that replicating IAV generates Z-RNAs, which activate ZBP1 in the nucleus of infected cells. ZBP1 then initiates RIPK3-mediated MLKL activation in the nucleus, resulting in nuclear envelope disruption, leakage of DNA into the cytosol, and eventual necroptosis. Cell death induced by nuclear MLKL was a potent activator of neutrophils, a cell type known to drive inflammatory pathology in virulent IAV disease. Consequently, MLKL-deficient mice manifest reduced nuclear disruption of lung epithelia, decreased neutrophil recruitment into infected lungs, and increased survival following a lethal dose of IAV. These results implicate Z-RNA as a new pathogen-associated molecular pattern and describe a ZBP1-initiated nucleus-to-plasma membrane "inside-out" death pathway with potentially pathogenic consequences in severe cases of influenza.
Assuntos
Vírus da Influenza A/genética , Necroptose/genética , Proteínas de Ligação a RNA/metabolismo , Animais , Apoptose/genética , Morte Celular/genética , Linhagem Celular Tumoral , Feminino , Vírus da Influenza A/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Necrose/metabolismo , Fosforilação , Proteínas Quinases/metabolismo , RNA/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , Proteínas de Ligação a RNA/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologiaRESUMO
Although mRNA vaccine efficacy against severe coronavirus disease 2019 remains high, variant emergence has prompted booster immunizations. However, the effects of repeated exposures to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens on memory T cells are poorly understood. Here, we utilize major histocompatibility complex multimers with single-cell RNA sequencing to profile SARS-CoV-2-responsive T cells ex vivo from humans with one, two or three antigen exposures, including vaccination, primary infection and breakthrough infection. Exposure order determined the distribution between spike-specific and non-spike-specific responses, with vaccination after infection leading to expansion of spike-specific T cells and differentiation to CCR7-CD45RA+ effectors. In contrast, individuals after breakthrough infection mount vigorous non-spike-specific responses. Analysis of over 4,000 epitope-specific T cell antigen receptor (TCR) sequences demonstrates that all exposures elicit diverse repertoires characterized by shared TCR motifs, confirmed by monoclonal TCR characterization, with no evidence for repertoire narrowing from repeated exposure. Our findings suggest that breakthrough infections diversify the T cell memory repertoire and current vaccination protocols continue to expand and differentiate spike-specific memory.
Assuntos
COVID-19 , SARS-CoV-2 , Linfócitos T CD8-Positivos , Humanos , Fenótipo , Receptores de Antígenos de Linfócitos T/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas , Vacinas de mRNARESUMO
The pool of beta cell-specific CD8+ T cells in type 1 diabetes (T1D) sustains an autoreactive potential despite having access to a constant source of antigen. To investigate the long-lived nature of these cells, we established a DNA methylation-based T cell 'multipotency index' and found that beta cell-specific CD8+ T cells retained a stem-like epigenetic multipotency score. Single-cell assay for transposase-accessible chromatin using sequencing confirmed the coexistence of naive and effector-associated epigenetic programs in individual beta cell-specific CD8+ T cells. Assessment of beta cell-specific CD8+ T cell anatomical distribution and the establishment of stem-associated epigenetic programs revealed that self-reactive CD8+ T cells isolated from murine lymphoid tissue retained developmentally plastic phenotypic and epigenetic profiles relative to the same cells isolated from the pancreas. Collectively, these data provide new insight into the longevity of beta cell-specific CD8+ T cell responses and document the use of this methylation-based multipotency index for investigating human and mouse CD8+ T cell differentiation.
Assuntos
Linfócitos T CD8-Positivos/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Células-Tronco Pluripotentes/fisiologia , Adolescente , Adulto , Animais , Autoantígenos/imunologia , Plasticidade Celular , Células Cultivadas , Metilação de DNA , Epigênese Genética , Feminino , Citometria de Fluxo , Humanos , Memória Imunológica , Masculino , Camundongos , Análise de Célula Única , Adulto JovemRESUMO
Influenza A, B and C viruses (IAV, IBV and ICV, respectively) circulate globally and infect humans, with IAV and IBV causing the most severe disease. CD8+ T cells confer cross-protection against IAV strains, however the responses of CD8+ T cells to IBV and ICV are understudied. We investigated the breadth of CD8+ T cell cross-recognition and provide evidence of CD8+ T cell cross-reactivity across IAV, IBV and ICV. We identified immunodominant CD8+ T cell epitopes from IBVs that were protective in mice and found memory CD8+ T cells directed against universal and influenza-virus-type-specific epitopes in the blood and lungs of healthy humans. Lung-derived CD8+ T cells displayed tissue-resident memory phenotypes. Notably, CD38+Ki67+CD8+ effector T cells directed against novel epitopes were readily detected in IAV- or IBV-infected pediatric and adult subjects. Our study introduces a new paradigm whereby CD8+ T cells confer unprecedented cross-reactivity across all influenza viruses, a key finding for the design of universal vaccines.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Reações Cruzadas/imunologia , Gammainfluenzavirus/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Influenza Humana/imunologia , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/virologia , Criança , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Vírus da Influenza A/fisiologia , Vírus da Influenza B/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Gammainfluenzavirus/fisiologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto JovemRESUMO
As the establishment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell memory in children remains largely unexplored, we recruited convalescent COVID-19 children and adults to define their circulating memory SARS-CoV-2-specific CD4+ and CD8+ T cells prior to vaccination. We analyzed epitope-specific T cells directly ex vivo using seven HLA class I and class II tetramers presenting SARS-CoV-2 epitopes, together with Spike-specific B cells. Unvaccinated children who seroconverted had comparable Spike-specific but lower ORF1a- and N-specific memory T cell responses compared with adults. This agreed with our TCR sequencing data showing reduced clonal expansion in children. A strong stem cell memory phenotype and common T cell receptor motifs were detected within tetramer-specific T cells in seroconverted children. Conversely, children who did not seroconvert had tetramer-specific T cells of predominantly naive phenotypes and diverse TCRαß repertoires. Our study demonstrates the generation of SARS-CoV-2-specific T cell memory with common TCRαß motifs in unvaccinated seroconverted children after their first virus encounter.
Assuntos
COVID-19 , SARS-CoV-2 , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Humanos , Memória Imunológica , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Glicoproteína da Espícula de CoronavírusRESUMO
Hepatocellular carcinoma (HCC) often develops following chronic hepatitis B virus (HBV) infection and responds poorly to immune checkpoint blockade. Here, we examined the antigen specificities of HCC-infiltrating T cells and their relevance to tumor control. Using highly multiplexed peptide-MHC tetramer staining of unexpanded cells from blood, liver, and tumor tissues from 46 HCC patients, we detected 91 different antigen-specific CD8+ T cell populations targeting HBV, neoantigen, tumor-associated, and disease-unrelated antigens. Parallel high-dimensional analysis delineated five distinct antigen-specific tissue-resident memory T (Trm) cell populations. Intratumoral and intrahepatic HBV-specific T cells were enriched for two Trm cell subsets that were PD-1loTOXlo, despite being clonally expanded. High frequencies of intratumoral terminally exhausted T cells were uncommon. Patients with tumor-infiltrating HBV-specific CD8+ Trm cells exhibited longer-term relapse-free survival. Thus, non-terminally exhausted HBV-specific CD8+ Trm cells show hallmarks of active involvement and effective antitumor response, implying that these cells could be harnessed for therapeutic purposes.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/imunologia , Memória Imunológica/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Antígenos de Neoplasias/imunologia , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/prevenção & controle , Receptor de Morte Celular Programada 1/metabolismo , Células Tumorais CultivadasRESUMO
To better understand primary and recall T cell responses during coronavirus disease 2019 (COVID-19), it is important to examine unmanipulated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cells. By using peptide-human leukocyte antigen (HLA) tetramers for direct ex vivo analysis, we characterized CD8+ T cells specific for SARS-CoV-2 epitopes in COVID-19 patients and unexposed individuals. Unlike CD8+ T cells directed toward subdominant epitopes (B7/N257, A2/S269, and A24/S1,208) CD8+ T cells specific for the immunodominant B7/N105 epitope were detected at high frequencies in pre-pandemic samples and at increased frequencies during acute COVID-19 and convalescence. SARS-CoV-2-specific CD8+ T cells in pre-pandemic samples from children, adults, and elderly individuals predominantly displayed a naive phenotype, indicating a lack of previous cross-reactive exposures. T cell receptor (TCR) analyses revealed diverse TCRαß repertoires and promiscuous αß-TCR pairing within B7/N105+CD8+ T cells. Our study demonstrates high naive precursor frequency and TCRαß diversity within immunodominant B7/N105-specific CD8+ T cells and provides insight into SARS-CoV-2-specific T cell origins and subsequent responses.
Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Epitopos Imunodominantes/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Motivos de Aminoácidos , Linfócitos T CD4-Positivos , Criança , Convalescença , Proteínas do Nucleocapsídeo de Coronavírus/química , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Epitopos Imunodominantes/química , Masculino , Pessoa de Meia-Idade , Fenótipo , Fosfoproteínas/química , Fosfoproteínas/imunologia , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T alfa-beta/química , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
Severe influenza A virus (IAV) infections can result in hyper-inflammation, lung injury and acute respiratory distress syndrome1-5 (ARDS), for which there are no effective pharmacological therapies. Necroptosis is an attractive entry point for therapeutic intervention in ARDS and related inflammatory conditions because it drives pathogenic lung inflammation and lethality during severe IAV infection6-8 and can potentially be targeted by receptor interacting protein kinase 3 (RIPK3) inhibitors. Here we show that a newly developed RIPK3 inhibitor, UH15-38, potently and selectively blocked IAV-triggered necroptosis in alveolar epithelial cells in vivo. UH15-38 ameliorated lung inflammation and prevented mortality following infection with laboratory-adapted and pandemic strains of IAV, without compromising antiviral adaptive immune responses or impeding viral clearance. UH15-38 displayed robust therapeutic efficacy even when administered late in the course of infection, suggesting that RIPK3 blockade may provide clinical benefit in patients with IAV-driven ARDS and other hyper-inflammatory pathologies.
Assuntos
Lesão Pulmonar , Necroptose , Infecções por Orthomyxoviridae , Inibidores de Proteínas Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Animais , Feminino , Humanos , Masculino , Camundongos , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/virologia , Células Epiteliais Alveolares/metabolismo , Vírus da Influenza A/classificação , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Lesão Pulmonar/complicações , Lesão Pulmonar/patologia , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/virologia , Camundongos Endogâmicos C57BL , Necroptose/efeitos dos fármacos , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/virologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/prevenção & controle , Síndrome do Desconforto Respiratório/virologiaRESUMO
Activated CD8+ T lymphocytes differentiate into heterogeneous subsets. Using super-resolution imaging, we found that prior to the first division, dynein-dependent vesicular transport polarized active TORC1 toward the microtubule-organizing center (MTOC) at the proximal pole. This active TORC1 was physically associated with active eIF4F, required for the translation of c-myc mRNA. As a consequence, c-myc-translating polysomes polarized toward the cellular pole proximal to the immune synapse, resulting in localized c-myc translation. Upon division, the TORC1-eIF4A complex preferentially sorted to the proximal daughter cell, facilitating asymmetric c-Myc synthesis. Transient disruption of eIF4A activity at first division skewed long-term cell fate trajectories to memory-like function. Using a genetic barcoding approach, we found that first-division sister cells often displayed differences in transcriptional profiles that largely correlated with c-Myc and TORC1 target genes. Our findings provide mechanistic insights as to how distinct T cell fate trajectories can be established during the first division.
Assuntos
Linfócitos T CD8-Positivos , Fator de Iniciação 4F em Eucariotos , Diferenciação Celular , Ativação Linfocitária , Alvo Mecanístico do Complexo 1 de Rapamicina/genéticaRESUMO
Cell death pathways regulate various homeostatic processes. Autoimmune lymphoproliferative syndrome (ALPS) in humans and lymphoproliferative (LPR) disease in mice result from abrogated CD95-induced apoptosis. Because caspase-8 mediates CD95 signaling, we applied genetic approaches to dissect the roles of caspase-8 in cell death and inflammation. Here, we describe oligomerization-deficient Caspase-8F122GL123G/F122GL123G and non-cleavable Caspase-8D387A/D387A mutant mice with defective caspase-8-mediated apoptosis. Although neither mouse developed LPR disease, removal of the necroptosis effector Mlkl from Caspase-8D387A/D387A mice revealed an inflammatory role of caspase-8. Ablation of one allele of Fasl, Fadd, or Ripk1 prevented the pathology of Casp8D387A/D387AMlkl-/- animals. Removing both Fadd alleles from these mice resulted in early lethality prior to post-natal day 15 (P15), which was prevented by co-ablation of either Ripk1 or Caspase-1. Our results suggest an in vivo role of the inflammatory RIPK1-caspase-8-FADD (FADDosome) complex and reveal a FADD-independent inflammatory role of caspase-8 that involves activation of an inflammasome.
Assuntos
Caspase 8/genética , Suscetibilidade a Doenças , Proteína de Domínio de Morte Associada a Fas/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Necroptose/genética , Animais , Apoptose/genética , Biomarcadores , Caspase 8/química , Caspase 8/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Imunofluorescência , Regulação da Expressão Gênica , Inflamassomos/metabolismo , Inflamação/mortalidade , Inflamação/patologia , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Mortalidade , Fenótipo , Multimerização ProteicaRESUMO
Cell therapies have yielded durable clinical benefits for patients with cancer, but the risks associated with the development of therapies from manipulated human cells are understudied. For example, we lack a comprehensive understanding of the mechanisms of toxicities observed in patients receiving T cell therapies, including recent reports of encephalitis caused by reactivation of human herpesvirus 6 (HHV-6)1. Here, through petabase-scale viral genomics mining, we examine the landscape of human latent viral reactivation and demonstrate that HHV-6B can become reactivated in cultures of human CD4+ T cells. Using single-cell sequencing, we identify a rare population of HHV-6 'super-expressors' (about 1 in 300-10,000 cells) that possess high viral transcriptional activity, among research-grade allogeneic chimeric antigen receptor (CAR) T cells. By analysing single-cell sequencing data from patients receiving cell therapy products that are approved by the US Food and Drug Administration2 or are in clinical studies3-5, we identify the presence of HHV-6-super-expressor CAR T cells in patients in vivo. Together, the findings of our study demonstrate the utility of comprehensive genomics analyses in implicating cell therapy products as a potential source contributing to the lytic HHV-6 infection that has been reported in clinical trials1,6-8 and may influence the design and production of autologous and allogeneic cell therapies.
Assuntos
Linfócitos T CD4-Positivos , Herpesvirus Humano 6 , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Ativação Viral , Latência Viral , Humanos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Ensaios Clínicos como Assunto , Regulação Viral da Expressão Gênica , Genômica , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/isolamento & purificação , Herpesvirus Humano 6/fisiologia , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Encefalite Infecciosa/complicações , Encefalite Infecciosa/virologia , Receptores de Antígenos Quiméricos/imunologia , Infecções por Roseolovirus/complicações , Infecções por Roseolovirus/virologia , Análise da Expressão Gênica de Célula Única , Carga ViralRESUMO
Only a small proportion of patients with cancer show lasting responses to immune checkpoint blockade (ICB)-based monotherapies. The RNA-editing enzyme ADAR1 is an emerging determinant of resistance to ICB therapy and prevents ICB responsiveness by repressing immunogenic double-stranded RNAs (dsRNAs), such as those arising from the dysregulated expression of endogenous retroviral elements (EREs)1-4. These dsRNAs trigger an interferon-dependent antitumour response by activating A-form dsRNA (A-RNA)-sensing proteins such as MDA-5 and PKR5. Here we show that ADAR1 also prevents the accrual of endogenous Z-form dsRNA elements (Z-RNAs), which were enriched in the 3' untranslated regions of interferon-stimulated mRNAs. Depletion or mutation of ADAR1 resulted in Z-RNA accumulation and activation of the Z-RNA sensor ZBP1, which culminated in RIPK3-mediated necroptosis. As no clinically viable ADAR1 inhibitors currently exist, we searched for a compound that can override the requirement for ADAR1 inhibition and directly activate ZBP1. We identified a small molecule, the curaxin CBL0137, which potently activates ZBP1 by triggering Z-DNA formation in cells. CBL0137 induced ZBP1-dependent necroptosis in cancer-associated fibroblasts and reversed ICB unresponsiveness in mouse models of melanoma. Collectively, these results demonstrate that ADAR1 represses endogenous Z-RNAs and identifies ZBP1-mediated necroptosis as a new determinant of tumour immunogenicity masked by ADAR1. Therapeutic activation of ZBP1-induced necroptosis provides a readily translatable avenue for rekindling the immune responsiveness of ICB-resistant human cancers.
Assuntos
Adenosina Desaminase , Necroptose , Neoplasias , Proteínas de Ligação a RNA , Regiões 3' não Traduzidas , Adenosina Desaminase/metabolismo , Animais , Fibroblastos Associados a Câncer , Carbazóis/farmacologia , Humanos , Imunoterapia/tendências , Interferons/metabolismo , Melanoma , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , RNA de Cadeia Dupla/imunologia , Proteínas de Ligação a RNA/metabolismoRESUMO
The identification of mechanisms to promote memory T (Tmem) cells has important implications for vaccination and anti-cancer immunotherapy1-4. Using a CRISPR-based screen for negative regulators of Tmem cell generation in vivo5, here we identify multiple components of the mammalian canonical BRG1/BRM-associated factor (cBAF)6,7. Several components of the cBAF complex are essential for the differentiation of activated CD8+ T cells into T effector (Teff) cells, and their loss promotes Tmem cell formation in vivo. During the first division of activated CD8+ T cells, cBAF and MYC8 frequently co-assort asymmetrically to the two daughter cells. Daughter cells with high MYC and high cBAF display a cell fate trajectory towards Teff cells, whereas those with low MYC and low cBAF preferentially differentiate towards Tmem cells. The cBAF complex and MYC physically interact to establish the chromatin landscape in activated CD8+ T cells. Treatment of naive CD8+ T cells with a putative cBAF inhibitor during the first 48 h of activation, before the generation of chimeric antigen receptor T (CAR-T) cells, markedly improves efficacy in a mouse solid tumour model. Our results establish cBAF as a negative determinant of Tmem cell fate and suggest that manipulation of cBAF early in T cell differentiation can improve cancer immunotherapy.
Assuntos
Linfócitos T CD8-Positivos , Diferenciação Celular , DNA Helicases , Complexos Multiproteicos , Proteínas Nucleares , Proteínas Proto-Oncogênicas c-myc , Fatores de Transcrição , Animais , Linfócitos T CD8-Positivos/citologia , DNA Helicases/metabolismo , Modelos Animais de Doenças , Memória Imunológica , Imunoterapia , Células T de Memória/citologia , Camundongos , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Neoplasias , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores de Antígenos Quiméricos , Fatores de Transcrição/metabolismoRESUMO
Compared to adults, infants suffer higher rates of hospitalization, severe clinical complications, and mortality due to influenza infection. We found that γδ T cells protected neonatal mice against mortality during influenza infection. γδ T cell deficiency did not alter viral clearance or interferon-γ production. Instead, neonatal influenza infection induced the accumulation of interleukin-17A (IL-17A)-producing γδ T cells, which was associated with IL-33 production by lung epithelial cells. Neonates lacking IL-17A-expressing γδ T cells or Il33 had higher mortality upon influenza infection. γδ T cells and IL-33 promoted lung infiltration of group 2 innate lymphoid cells and regulatory T cells, resulting in increased amphiregulin secretion and tissue repair. In influenza-infected children, IL-17A, IL-33, and amphiregulin expression were correlated, and increased IL-17A levels in nasal aspirates were associated with better clinical outcomes. Our results indicate that γδ T cells are required in influenza-infected neonates to initiate protective immunity and mediate lung homeostasis.
Assuntos
Vírus da Influenza A/fisiologia , Influenza Humana/imunologia , Interleucina-17/metabolismo , Pulmão/imunologia , Infecções por Orthomyxoviridae/imunologia , Linfócitos T/imunologia , Células Th2/imunologia , Adulto , Anfirregulina/metabolismo , Animais , Células Cultivadas , Criança , Humanos , Imunidade , Recém-Nascido , Interleucina-33/metabolismo , Camundongos , Prognóstico , Receptores de Antígenos de Linfócitos T gama-delta/metabolismoRESUMO
Severe respiratory infections can result in acute respiratory distress syndrome (ARDS)1. There are no effective pharmacological therapies that have been shown to improve outcomes for patients with ARDS. Although the host inflammatory response limits spread of and eventually clears the pathogen, immunopathology is a major contributor to tissue damage and ARDS1,2. Here we demonstrate that respiratory viral infection induces distinct fibroblast activation states, which we term extracellular matrix (ECM)-synthesizing, damage-responsive and interferon-responsive states. We provide evidence that excess activity of damage-responsive lung fibroblasts drives lethal immunopathology during severe influenza virus infection. By producing ECM-remodelling enzymes-in particular the ECM protease ADAMTS4-and inflammatory cytokines, damage-responsive fibroblasts modify the lung microenvironment to promote robust immune cell infiltration at the expense of lung function. In three cohorts of human participants, the levels of ADAMTS4 in the lower respiratory tract were associated with the severity of infection with seasonal or avian influenza virus. A therapeutic agent that targets the ECM protease activity of damage-responsive lung fibroblasts could provide a promising approach to preserving lung function and improving clinical outcomes following severe respiratory infections.
Assuntos
Proteína ADAMTS4/metabolismo , Fibroblastos/enzimologia , Fibroblastos/patologia , Vírus da Influenza A/patogenicidade , Pulmão/patologia , Pulmão/fisiopatologia , Proteína ADAMTS4/antagonistas & inibidores , Animais , Aves/virologia , Matriz Extracelular/enzimologia , Perfilação da Expressão Gênica , Humanos , Influenza Aviária/virologia , Influenza Humana/patologia , Influenza Humana/terapia , Influenza Humana/virologia , Interferons/imunologia , Interferons/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Pulmão/enzimologia , Pulmão/virologia , Camundongos , Síndrome do Desconforto Respiratório/enzimologia , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Síndrome do Desconforto Respiratório/virologia , Estações do Ano , Análise de Célula Única , Células Estromais/metabolismoRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.