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Regulatory myeloid immune cells, such as myeloid-derived suppressor cells (MDSCs), populate inflamed or cancerous tissue and block immune cell effector functions. The lack of mechanistic insight into MDSC suppressive activity and a marker for their identification has hampered attempts to overcome T cell inhibition and unleash anti-cancer immunity. Here, we report that human MDSCs were characterized by strongly reduced metabolism and conferred this compromised metabolic state to CD8+ T cells, thereby paralyzing their effector functions. We identified accumulation of the dicarbonyl radical methylglyoxal, generated by semicarbazide-sensitive amine oxidase, to cause the metabolic phenotype of MDSCs and MDSC-mediated paralysis of CD8+ T cells. In a murine cancer model, neutralization of dicarbonyl activity overcame MDSC-mediated T cell suppression and, together with checkpoint inhibition, improved the efficacy of cancer immune therapy. Our results identify the dicarbonyl methylglyoxal as a marker metabolite for MDSCs that mediates T cell paralysis and can serve as a target to improve cancer immune therapy.
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Linfócitos T CD8-Positivos/imunologia , Imunoterapia/métodos , Melanoma/imunologia , Células Supressoras Mieloides/imunologia , Aldeído Pirúvico/metabolismo , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Linfócitos T CD8-Positivos/transplante , Comunicação Celular , Proliferação de Células , Humanos , Tolerância Imunológica , Ativação Linfocitária , Melanoma Experimental , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais , Receptor de Morte Celular Programada 1/metabolismoRESUMO
Cachexia represents a leading cause of morbidity and mortality in various cancers, chronic inflammation and infections. Understanding of the mechanisms that drive cachexia has remained limited, especially for infection-associated cachexia (IAC). In the present paper we describe a model of reversible cachexia in mice with chronic viral infection and identify an essential role for CD8+ T cells in IAC. Cytokines linked to cancer-associated cachexia did not contribute to IAC. Instead, virus-specific CD8+ T cells caused morphologic and molecular changes in the adipose tissue, which led to depletion of lipid stores. These changes occurred at a time point that preceded the peak of the CD8+ T cell response and required T cell-intrinsic type I interferon signaling and antigen-specific priming. Our results link systemic antiviral immune responses to adipose-tissue remodeling and reveal an underappreciated role of CD8+ T cells in IAC.
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Linfócitos T CD8-Positivos/imunologia , Caquexia/etiologia , Viroses/complicações , Viroses/imunologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Tecido Adiposo/virologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Caquexia/diagnóstico por imagem , Caquexia/metabolismo , Caquexia/patologia , Doença Crônica , Citocinas/sangue , Citocinas/metabolismo , Feminino , Interferon Tipo I/metabolismo , Metabolismo dos Lipídeos , Lipólise , Ativação Linfocitária/imunologia , Vírus da Coriomeningite Linfocítica , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Transdução de Sinais , Viroses/virologiaRESUMO
Glucagon and thyroid hormone (T3) exhibit therapeutic potential for metabolic disease but also exhibit undesired effects. We achieved synergistic effects of these two hormones and mitigation of their adverse effects by engineering chemical conjugates enabling delivery of both activities within one precisely targeted molecule. Coordinated glucagon and T3 actions synergize to correct hyperlipidemia, steatohepatitis, atherosclerosis, glucose intolerance, and obesity in metabolically compromised mice. We demonstrate that each hormonal constituent mutually enriches cellular processes in hepatocytes and adipocytes via enhanced hepatic cholesterol metabolism and white fat browning. Synchronized signaling driven by glucagon and T3 reciprocally minimizes the inherent harmful effects of each hormone. Liver-directed T3 action offsets the diabetogenic liability of glucagon, and glucagon-mediated delivery spares the cardiovascular system from adverse T3 action. Our findings support the therapeutic utility of integrating these hormones into a single molecular entity that offers unique potential for treatment of obesity, type 2 diabetes, and cardiovascular disease.
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Glucagon/uso terapêutico , Doenças Metabólicas/tratamento farmacológico , Tri-Iodotironina/efeitos dos fármacos , Animais , Aterosclerose/tratamento farmacológico , Peso Corporal/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Engenharia Química/métodos , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Combinação de Medicamentos , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Glucagon/efeitos adversos , Glucagon/química , Glucagon/farmacologia , Hiperglicemia/tratamento farmacológico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Terapia de Alvo Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Tri-Iodotironina/efeitos adversos , Tri-Iodotironina/química , Tri-Iodotironina/farmacologiaRESUMO
In contrast to most other malignancies, hepatocellular carcinoma (HCC), which accounts for approximately 90% of primary liver cancers, arises almost exclusively in the setting of chronic inflammation. Irrespective of etiology, a typical sequence of chronic necroinflammation, compensatory liver regeneration, induction of liver fibrosis and subsequent cirrhosis often precedes hepatocarcinogenesis. The liver is a central immunomodulator that ensures organ and systemic protection while maintaining immunotolerance. Deregulation of this tightly controlled liver immunological network is a hallmark of chronic liver disease and HCC. Notably, immunotherapies have raised hope for the successful treatment of advanced HCC. Here we summarize the roles of specific immune cell subsets in chronic liver disease, with a focus on non-alcoholic steatohepatitis and HCC. We review new advances in immunotherapeutic approaches for the treatment of HCC and discuss the challenges posed by the immunotolerant hepatic environment and the dual roles of adaptive and innate immune cells in HCC.
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Carcinogênese/imunologia , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Humanos , Inflamação/complicações , Inflamação/imunologiaRESUMO
Persistent viral infections are characterized by the simultaneous presence of chronic inflammation and T cell dysfunction. In prototypic models of chronicity--infection with human immunodeficiency virus (HIV) or lymphocytic choriomeningitis virus (LCMV)--we used transcriptome-based modeling to reveal that CD4(+) T cells were co-exposed not only to multiple inhibitory signals but also to tumor-necrosis factor (TNF). Blockade of TNF during chronic infection with LCMV abrogated the inhibitory gene-expression signature in CD4(+) T cells, including reduced expression of the inhibitory receptor PD-1, and reconstituted virus-specific immunity, which led to control of infection. Preventing signaling via the TNF receptor selectively in T cells sufficed to induce these effects. Targeted immunological interventions to disrupt the TNF-mediated link between chronic inflammation and T cell dysfunction might therefore lead to therapies to overcome persistent viral infection.
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Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Citometria de Fluxo , Células HEK293 , HIV/fisiologia , Infecções por HIV/genética , Infecções por HIV/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Immunoblotting , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/imunologia , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Transcriptoma/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Adulto JovemRESUMO
Ectopic lymphoid-like structures (ELSs) are often observed in cancer, yet their function is obscure. Although ELSs signify good prognosis in certain malignancies, we found that hepatic ELSs indicated poor prognosis for hepatocellular carcinoma (HCC). We studied an HCC mouse model that displayed abundant ELSs and found that they constituted immunopathological microniches wherein malignant hepatocyte progenitor cells appeared and thrived in a complex cellular and cytokine milieu until gaining self-sufficiency. The egress of progenitor cells and tumor formation were associated with the autocrine production of cytokines previously provided by the niche. ELSs developed via cooperation between the innate immune system and adaptive immune system, an event facilitated by activation of the transcription factor NF-κB and abolished by depletion of T cells. Such aberrant immunological foci might represent new targets for cancer therapy.
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Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Tecido Linfoide/imunologia , Células-Tronco Neoplásicas/imunologia , Nicho de Células-Tronco/imunologia , Imunidade Adaptativa/genética , Imunidade Adaptativa/imunologia , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Hibridização Genômica Comparativa , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Hepatócitos/imunologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Quinase I-kappa B/metabolismo , Imunidade Inata/genética , Imunidade Inata/imunologia , Immunoblotting , Hibridização In Situ , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/imunologia , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nicho de Células-Tronco/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma/genética , Transcriptoma/imunologiaRESUMO
The differentiation of follicular dendritic cells (FDC) is essential to the remarkable microanatomic plasticity of lymphoid follicles. Here we show that FDC arise from ubiquitous perivascular precursors (preFDC) expressing platelet-derived growth factor receptor ß (PDGFRß). PDGFRß-Cre-driven reporter gene recombination resulted in FDC labeling, whereas conditional ablation of PDGFRß(+)-derived cells abolished FDC, indicating that FDC originate from PDGFRß(+) cells. Lymphotoxin-α-overexpressing prion protein (PrP)(+) kidneys developed PrP(+) FDC after transplantation into PrP(-) mice, confirming that preFDC exist outside lymphoid organs. Adipose tissue-derived PDGFRß(+) stromal-vascular cells responded to FDC maturation factors and, when transplanted into lymphotoxin ß receptor (LTßR)(-) kidney capsules, differentiated into Mfge8(+)CD21/35(+)FcγRIIß(+)PrP(+) FDC capable of trapping immune complexes and recruiting B cells. Spleens of lymphocyte-deficient mice contained perivascular PDGFRß(+) FDC precursors whose expansion required both lymphoid tissue inducer (LTi) cells and lymphotoxin. The ubiquity of preFDC and their strategic location at blood vessels may explain the de novo generation of organized lymphoid tissue at sites of lymphocytic inflammation.
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Vasos Sanguíneos/citologia , Células Dendríticas Foliculares/citologia , Baço/citologia , Células-Tronco/citologia , Animais , Linfócitos B/imunologia , Células Dendríticas Foliculares/imunologia , Células Dendríticas Foliculares/metabolismo , Centro Germinativo/citologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Inflamação/patologia , Células Matadoras Naturais/imunologia , Camundongos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Organismos Livres de Patógenos Específicos , Baço/metabolismoRESUMO
Nonalcoholic steatohepatitis (NASH) is a manifestation of systemic metabolic disease related to obesity, and causes liver disease and cancer1,2. The accumulation of metabolites leads to cell stress and inflammation in the liver3, but mechanistic understandings of liver damage in NASH are incomplete. Here, using a preclinical mouse model that displays key features of human NASH (hereafter, NASH mice), we found an indispensable role for T cells in liver immunopathology. We detected the hepatic accumulation of CD8 T cells with phenotypes that combined tissue residency (CXCR6) with effector (granzyme) and exhaustion (PD1) characteristics. Liver CXCR6+ CD8 T cells were characterized by low activity of the FOXO1 transcription factor, and were abundant in NASH mice and in patients with NASH. Mechanistically, IL-15 induced FOXO1 downregulation and CXCR6 upregulation, which together rendered liver-resident CXCR6+ CD8 T cells susceptible to metabolic stimuli (including acetate and extracellular ATP) and collectively triggered auto-aggression. CXCR6+ CD8 T cells from the livers of NASH mice or of patients with NASH had similar transcriptional signatures, and showed auto-aggressive killing of cells in an MHC-class-I-independent fashion after signalling through P2X7 purinergic receptors. This killing by auto-aggressive CD8 T cells fundamentally differed from that by antigen-specific cells, which mechanistically distinguishes auto-aggressive and protective T cell immunity.
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Linfócitos T CD8-Positivos/imunologia , Fígado/imunologia , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores CXCR6/imunologia , Acetatos/farmacologia , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/patologia , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Interleucina-15/imunologia , Interleucina-15/farmacologia , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Humoral autoimmunity paralleled by the accumulation of follicular helper T cells (T(FH) cells) is linked to mutation of the gene encoding the RNA-binding protein roquin-1. Here we found that T cells lacking roquin caused pathology in the lung and accumulated as cells of the T(H)17 subset of helper T cells in the lungs. Roquin inhibited T(H)17 cell differentiation and acted together with the endoribonuclease regnase-1 to repress target mRNA encoding the T(H)17 cell-promoting factors IL-6, ICOS, c-Rel, IRF4, IκBNS and IκBζ. This cooperation required binding of RNA by roquin and the nuclease activity of regnase-1. Upon recognition of antigen by the T cell antigen receptor (TCR), roquin and regnase-1 proteins were cleaved by the paracaspase MALT1. Thus, this pathway acts as a 'rheostat' by translating TCR signal strength via graded inactivation of post-transcriptional repressors and differential derepression of targets to enhance T(H)17 differentiation.
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Caspases/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Ribonucleases/metabolismo , Células Th17/citologia , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação/imunologia , Diferenciação Celular/imunologia , Linhagem Celular , Genes rel/genética , Células HEK293 , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Fatores Reguladores de Interferon/genética , Interleucina-6/genética , Peptídeos e Proteínas de Sinalização Intracelular , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas Nucleares/genética , Proteínas/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência , Células Th17/imunologia , Ubiquitina-Proteína Ligases/genéticaRESUMO
BACKGROUND: Cardiac hypertrophy is characterized by remodeling of the myocardium, which involves alterations in the ECM (extracellular matrix) and cardiomyocyte structure. These alterations critically contribute to impaired contractility and relaxation, ultimately leading to heart failure. Emerging evidence implicates that extracellular signaling molecules are critically involved in the pathogenesis of cardiac hypertrophy and remodeling. The immunophilin CyPA (cyclophilin A) has been identified as a potential culprit. In this study, we aimed to unravel the interplay between eCyPA (extracellular CyPA) and myocardial dysfunction and evaluate the therapeutic potential of inhibiting its extracellular accumulation to improve heart function. METHODS: Employing a multidisciplinary approach encompassing in silico, in vitro, in vivo, and ex vivo experiments we studied a mouse model of cardiac hypertrophy and human heart specimen to decipher the interaction of CyPA and the cardiac microenvironment in highly relevant pre-/clinical settings. Myocardial expression of CyPA (immunohistology) and the inflammatory transcriptome (NanoString) was analyzed in human cardiac tissue derived from patients with nonischemic, noninflammatory congestive heart failure (n=187). These analyses were paralleled by a mouse model of Ang (angiotensin) II-induced heart failure, which was assessed by functional (echocardiography), structural (immunohistology, atomic force microscopy), and biomolecular (Raman spectroscopy) analyses. The effect of inhibiting eCyPA in the cardiac microenvironment was evaluated using a newly developed neutralizing anti-eCyPA monoclonal antibody. RESULTS: We observed a significant accumulation of eCyPA in both human and murine-failing hearts. Importantly, higher eCyPA expression was associated with poor clinical outcomes in patients (P=0.043) and contractile dysfunction in mice (Pearson correlation coefficient, -0.73). Further, myocardial expression of eCyPA was critically associated with an increase in myocardial hypertrophy, inflammation, fibrosis, stiffness, and cardiac dysfunction in vivo. Antibody-based inhibition of eCyPA prevented (Ang II)-induced myocardial remodeling and dysfunction in mice. CONCLUSIONS: Our study provides strong evidence of the pathogenic role of eCyPA in remodeling, myocardial stiffening, and dysfunction in heart failure. The findings suggest that antibody-based inhibition of eCyPA may offer a novel therapeutic strategy for nonischemic heart failure. Further research is needed to evaluate the translational potential of these interventions in human patients with cardiac hypertrophy.
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Colonization by the microbiota causes a marked stimulation of B cells and induction of immunoglobulin, but mammals colonized with many taxa have highly complex and individualized immunoglobulin repertoires1,2. Here we use a simplified model of defined transient exposures to different microbial taxa in germ-free mice3 to deconstruct how the microbiota shapes the B cell pool and its functional responsiveness. We followed the development of the immunoglobulin repertoire in B cell populations, as well as single cells by deep sequencing. Microbial exposures at the intestinal mucosa generated oligoclonal responses that differed from those of germ-free mice, and from the diverse repertoire that was generated after intravenous systemic exposure to microbiota. The IgA repertoire-predominantly to cell-surface antigens-did not expand after dose escalation, whereas increased systemic exposure broadened the IgG repertoire to both microbial cytoplasmic and cell-surface antigens. These microbial exposures induced characteristic immunoglobulin heavy-chain repertoires in B cells, mainly at memory and plasma cell stages. Whereas sequential systemic exposure to different microbial taxa diversified the IgG repertoire and facilitated alternative specific responses, sequential mucosal exposure produced limited overlapping repertoires and the attrition of initial IgA binding specificities. This shows a contrast between a flexible response to systemic exposure with the need to avoid fatal sepsis, and a restricted response to mucosal exposure that reflects the generic nature of host-microbial mutualism in the mucosa.
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Linfócitos B/citologia , Linfócitos B/imunologia , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Simbiose/imunologia , Administração Intravenosa , Administração Oral , Animais , Clostridiales/imunologia , Clostridiales/isolamento & purificação , Escherichia coli/imunologia , Escherichia coli/isolamento & purificação , Feminino , Vida Livre de Germes , Imunoglobulina A/química , Imunoglobulina A/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Memória Imunológica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasmócitos/citologia , Plasmócitos/imunologia , Priming de RepetiçãoRESUMO
Lymphotoxin ß-receptor (LTßR) signalling promotes lymphoid neogenesis and the development of tertiary lymphoid structures1,2, which are associated with severe chronic inflammatory diseases that span several organ systems3-6. How LTßR signalling drives chronic tissue damage particularly in the lung, the mechanism(s) that regulate this process, and whether LTßR blockade might be of therapeutic value have remained unclear. Here we demonstrate increased expression of LTßR ligands in adaptive and innate immune cells, enhanced non-canonical NF-κB signalling, and enriched LTßR target gene expression in lung epithelial cells from patients with smoking-associated chronic obstructive pulmonary disease (COPD) and from mice chronically exposed to cigarette smoke. Therapeutic inhibition of LTßR signalling in young and aged mice disrupted smoking-related inducible bronchus-associated lymphoid tissue, induced regeneration of lung tissue, and reverted airway fibrosis and systemic muscle wasting. Mechanistically, blockade of LTßR signalling dampened epithelial non-canonical activation of NF-κB, reduced TGFß signalling in airways, and induced regeneration by preventing epithelial cell death and activating WNT/ß-catenin signalling in alveolar epithelial progenitor cells. These findings suggest that inhibition of LTßR signalling represents a viable therapeutic option that combines prevention of tertiary lymphoid structures1 and inhibition of apoptosis with tissue-regenerative strategies.
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Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Receptor beta de Linfotoxina/antagonistas & inibidores , Regeneração/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/agonistas , Imunidade Adaptativa , Envelhecimento/metabolismo , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Apoptose/efeitos dos fármacos , Enfisema/metabolismo , Feminino , Humanos , Imunidade Inata , Pulmão/metabolismo , Receptor beta de Linfotoxina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fumaça/efeitos adversos , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismoRESUMO
Cellular senescence is characterized by an irreversible cell cycle arrest as well as a pro-inflammatory phenotype, thought to contribute to aging and age-related diseases. Neutrophils have essential roles in inflammatory responses; however, in certain contexts their abundance is associated with a number of age-related diseases, including liver disease. The relationship between neutrophils and cellular senescence is not well understood. Here, we show that telomeres in non-immune cells are highly susceptible to oxidative damage caused by neighboring neutrophils. Neutrophils cause telomere dysfunction both in vitro and ex vivo in a ROS-dependent manner. In a mouse model of acute liver injury, depletion of neutrophils reduces telomere dysfunction and senescence. Finally, we show that senescent cells mediate the recruitment of neutrophils to the aged liver and propose that this may be a mechanism by which senescence spreads to surrounding cells. Our results suggest that interventions that counteract neutrophil-induced senescence may be beneficial during aging and age-related disease.
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Lesão Pulmonar Aguda/imunologia , Tetracloreto de Carbono/efeitos adversos , Neutrófilos/citologia , Espécies Reativas de Oxigênio/metabolismo , Encurtamento do Telômero , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Animais , Linhagem Celular , Senescência Celular , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Masculino , Camundongos , Neutrófilos/metabolismo , Estresse Oxidativo , Comunicação ParácrinaRESUMO
BACKGROUND & AIMS: High expression of phosphatidylinositol 4-kinase III alpha (PI4KIIIα) correlates with poor survival rates in patients with hepatocellular carcinoma. In addition, hepatitis C virus (HCV) infections activate PI4KIIIα and contribute to hepatocellular carcinoma progression. We aimed at mechanistically understanding the impact of PI4KIIIα on the progression of liver cancer and the potential contribution of HCV in this process. METHODS: Several hepatic cell culture and mouse models were used to study the functional importance of PI4KIIIα on liver pathogenesis. Antibody arrays, gene silencing, and PI4KIIIα-specific inhibitor were applied to identify the involved signaling pathways. The contribution of HCV was examined by using HCV infection or overexpression of its nonstructural protein. RESULTS: High PI4KIIIα expression and/or activity induced cytoskeletal rearrangements via increased phosphorylation of paxillin and cofilin. This led to morphologic alterations and higher migratory and invasive properties of liver cancer cells. We further identified the liver-specific lipid kinase phosphatidylinositol 3-kinase C2 domain-containing subunit gamma (PIK3C2γ) working downstream of PI4KIIIα in regulation of the cytoskeleton. PIK3C2γ generates plasma membrane phosphatidylinositol 3,4-bisphosphate-enriched, invadopodia-like structures that regulate cytoskeletal reorganization by promoting Akt2 phosphorylation. CONCLUSIONS: PI4KIIIα regulates cytoskeleton organization via PIK3C2γ/Akt2/paxillin-cofilin to favor migration and invasion of liver cancer cells. These findings provide mechanistic insight into the contribution of PI4KIIIα and HCV to the progression of liver cancer and identify promising targets for therapeutic intervention.
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Fatores de Despolimerização de Actina , Carcinoma Hepatocelular , Movimento Celular , Citoesqueleto , Neoplasias Hepáticas , Invasividade Neoplásica , Paxilina , Transdução de Sinais , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Humanos , Animais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Paxilina/metabolismo , Camundongos , Fatores de Despolimerização de Actina/metabolismo , Fatores de Despolimerização de Actina/genética , Fosforilação , Hepacivirus , Linhagem Celular Tumoral , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Células Hep G2 , Hepatite C/patologia , Hepatite C/metabolismo , Hepatite C/virologia , Interferência de RNARESUMO
Tertiary lymphoid structures (TLS) resemble follicles of secondary lymphoid organs and develop in nonlymphoid tissues during inflammation and cancer. Which cell types and signals drive the development of TLS is largely unknown. To investigate early events of TLS development in the lungs, we repeatedly instilled p(I:C) plus ovalbumin (Ova) intranasally. This induced TLS ranging from lymphocytic aggregates to organized and functional structures containing germinal centers. We found that TLS development is independent of FAP+ fibroblasts, alveolar macrophages, or CCL19 but crucially depends on type I interferon (IFN-I). Mechanistically, IFN-I initiates two synergistic pathways that culminate in the development of TLS. On the one hand, IFN-I induces lymphotoxin (LT)α in lymphoid cells, which stimulate stromal cells to produce the B-cell-attracting chemokine CXCL13 through LTßR-signaling. On the other hand, IFN-I is sensed by stromal cells that produce the T-cell-attracting chemokines CXCL9, CXCL10 as well as CCL19 and CCL21 independently of LTßR. Consequently, B-cell aggregates develop within a week, whereas follicular dendritic cells and germinal centers appear after 3 weeks. Thus, sustained production of IFN-I together with an antigen is essential for the induction of functional TLS in the lungs.
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Chronic infection is difficult to overcome because of exhaustion or depletion of cytotoxic effector CD8(+) T cells (cytotoxic T lymphoytes (CTLs)). Here we report that signaling via Toll-like receptors (TLRs) induced intrahepatic aggregates of myeloid cells that enabled the population expansion of CTLs (iMATEs: 'intrahepatic myeloid-cell aggregates for T cell population expansion') without causing immunopathology. In the liver, CTL proliferation was restricted to iMATEs that were composed of inflammatory monocyte-derived CD11b(+) cells. Signaling via tumor-necrosis factor (TNF) caused iMATE formation that facilitated costimulation dependent on the receptor OX40 for expansion of the CTL population. The iMATEs arose during acute viral infection but were absent during chronic viral infection, yet they were still induced by TLR signaling. Such hepatic expansion of the CTL population controlled chronic viral infection of the liver after vaccination with DNA. Thus, iMATEs are dynamic structures that overcome regulatory cues that limit the population expansion of CTLs during chronic infection and can be used in new therapeutic vaccination strategies.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Hepatopatias/imunologia , Coriomeningite Linfocítica/imunologia , Células Mieloides/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Animais Recém-Nascidos , Antígeno CD11b/imunologia , Antígeno CD11b/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Doença Crônica , Citometria de Fluxo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imunoterapia , Fígado/imunologia , Fígado/metabolismo , Fígado/virologia , Hepatopatias/terapia , Hepatopatias/virologia , Coriomeningite Linfocítica/terapia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Células Mieloides/metabolismo , Receptores OX40/imunologia , Receptores OX40/metabolismo , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/metabolismo , Receptor Toll-Like 9/imunologia , Receptor Toll-Like 9/metabolismoRESUMO
Sickness behavior and cognitive dysfunction occur frequently by unknown mechanisms in virus-infected individuals with malignancies treated with type I interferons (IFNs) and in patients with autoimmune disorders. We found that during sickness behavior, single-stranded RNA viruses, double-stranded RNA ligands, and IFNs shared pathways involving engagement of melanoma differentiation-associated protein 5 (MDA5), retinoic acid-inducible gene 1 (RIG-I), and mitochondrial antiviral signaling protein (MAVS), and subsequently induced IFN responses specifically in brain endothelia and epithelia of mice. Behavioral alterations were specifically dependent on brain endothelial and epithelial IFN receptor chain 1 (IFNAR). Using gene profiling, we identified that the endothelia-derived chemokine ligand CXCL10 mediated behavioral changes through impairment of synaptic plasticity. These results identified brain endothelial and epithelial cells as natural gatekeepers for virus-induced sickness behavior, demonstrated tissue specific IFNAR engagement, and established the CXCL10-CXCR3 axis as target for the treatment of behavioral changes during virus infection and type I IFN therapy.
Assuntos
Encéfalo/citologia , Quimiocina CXCL10/imunologia , Transtornos Cognitivos/genética , Células Endoteliais/imunologia , Células Epiteliais/imunologia , Comportamento de Doença/fisiologia , Receptor de Interferon alfa e beta/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Encéfalo/imunologia , Comunicação Celular/imunologia , Células Cultivadas , Transtornos Cognitivos/psicologia , Proteína DEAD-box 58 , RNA Helicases DEAD-box/metabolismo , Endotélio/citologia , Endotélio/imunologia , Epitélio/imunologia , Interferon Tipo I/uso terapêutico , Helicase IFIH1 Induzida por Interferon , Masculino , Camundongos , RNA de Cadeia Dupla/genética , Receptor de Interferon alfa e beta/imunologia , Receptores CXCR3/imunologia , Transdução de Sinais/imunologia , Viroses/imunologiaRESUMO
INTRODUCTION: The Hippo pathway and its transcriptional effectors yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are targets for cancer therapy. It is important to determine if the activation of one factor compensates for the inhibition of the other. Moreover, it is unknown if YAP/TAZ-directed perturbation affects cell-cell communication of non-malignant liver cells. MATERIALS AND METHODS: To investigate liver-specific phenotypes caused by YAP and TAZ inactivation, we generated mice with hepatocyte (HC) and biliary epithelial cell (BEC)-specific deletions for both factors (YAPKO, TAZKO and double knock-out (DKO)). Immunohistochemistry, single-cell sequencing, and proteomics were used to analyze liver tissues and serum. RESULTS: The loss of BECs, liver fibrosis, and necrosis characterized livers from YAPKO and DKO mice. This phenotype was weakened in DKO tissues compared to specimens from YAPKO animals. After depletion of YAP in HCs and BECs, YAP expression was induced in non-parenchymal cells (NPCs) in a cholestasis-independent manner. YAP positivity was detected in subgroups of Kupffer cells (KCs) and endothelial cells (ECs). The secretion of pro-inflammatory chemokines and cytokines such as C-X-C motif chemokine ligand 11 (CXCL11), fms-related receptor tyrosine kinase 3 ligand (FLT3L), and soluble intercellular adhesion molecule-1 (ICAM1) was increased in the serum of YAPKO animals. YAP activation in NPCs could contribute to inflammation via TEA domain transcription factor (TEAD)-dependent transcriptional regulation of secreted factors. CONCLUSION: YAP inactivation in HCs and BECs causes liver damage, and concomitant TAZ deletion does not enhance but reduces this phenotype. Additionally, we present a new mechanism by which YAP contributes to cell-cell communication originating from NPCs.
Assuntos
Comunicação Celular , Fígado , Proteínas de Sinalização YAP , Animais , Camundongos , Comunicação Celular/genética , Células Endoteliais , Hepatócitos , Ligantes , Fígado/metabolismo , Proteínas de Sinalização YAP/genética , Proteínas de Sinalização YAP/metabolismoRESUMO
BACKGROUND & AIMS: As pancreatic ductal adenocarcinoma (PDAC) continues to be recalcitrant to therapeutic interventions, including poor response to immunotherapy, albeit effective in other solid malignancies, a more nuanced understanding of the immune microenvironment in PDAC is urgently needed. We aimed to unveil a detailed view of the immune micromilieu in PDAC using a spatially resolved multimodal single-cell approach. METHODS: We applied single-cell RNA sequencing, spatial transcriptomics, multiplex immunohistochemistry, and mass cytometry to profile the immune compartment in treatment-naïve PDAC tumors and matched adjacent normal pancreatic tissue, as well as in the systemic circulation. We determined prognostic associations of immune signatures and performed a meta-analysis of the immune microenvironment in PDAC and lung adenocarcinoma on single-cell level. RESULTS: We provided a spatially resolved fine map of the immune landscape in PDAC. We substantiated the exhausted phenotype of CD8 T cells and immunosuppressive features of myeloid cells, and highlighted immune subsets with potentially underappreciated roles in PDAC that diverged from immune populations within adjacent normal areas, particularly CD4 T cell subsets and natural killer T cells that are terminally exhausted and acquire a regulatory phenotype. Differential analysis of immune phenotypes in PDAC and lung adenocarcinoma revealed the presence of extraordinarily immunosuppressive subtypes in PDAC, along with a distinctive immune checkpoint composition. CONCLUSIONS: Our study sheds light on the multilayered immune dysfunction in PDAC and presents a holistic view of the immune landscape in PDAC and lung adenocarcinoma, providing a comprehensive resource for functional studies and the exploration of therapeutically actionable targets in PDAC.