RESUMEN
BACKGROUND: Prostate cancer develops through malignant transformation of the prostate epithelium in a stepwise, mutation-driven process. Although activator protein-1 transcription factors such as JUN have been implicated as potential oncogenic drivers, the molecular programs contributing to prostate cancer progression are not fully understood. METHODS: We analyzed JUN expression in clinical prostate cancer samples across different stages and investigated its functional role in a Pten-deficient mouse model. We performed histopathological examinations, transcriptomic analyses and explored the senescence-associated secretory phenotype in the tumor microenvironment. RESULTS: Elevated JUN levels characterized early-stage prostate cancer and predicted improved survival in human and murine samples. Immune-phenotyping of Pten-deficient prostates revealed high accumulation of tumor-infiltrating leukocytes, particularly innate immune cells, neutrophils and macrophages as well as high levels of STAT3 activation and IL-1ß production. Jun depletion in a Pten-deficient background prevented immune cell attraction which was accompanied by significant reduction of active STAT3 and IL-1ß and accelerated prostate tumor growth. Comparative transcriptome profiling of prostate epithelial cells revealed a senescence-associated gene signature, upregulation of pro-inflammatory processes involved in immune cell attraction and of chemokines such as IL-1ß, TNF-α, CCL3 and CCL8 in Pten-deficient prostates. Strikingly, JUN depletion reversed both the senescence-associated secretory phenotype and senescence-associated immune cell infiltration but had no impact on cell cycle arrest. As a result, JUN depletion in Pten-deficient prostates interfered with the senescence-associated immune clearance and accelerated tumor growth. CONCLUSIONS: Our results suggest that JUN acts as tumor-suppressor and decelerates the progression of prostate cancer by transcriptional regulation of senescence- and inflammation-associated genes. This study opens avenues for novel treatment strategies that could impede disease progression and improve patient outcomes.
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Progresión de la Enfermedad , Fosfohidrolasa PTEN , Neoplasias de la Próstata , Microambiente Tumoral , Masculino , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Animales , Ratones , Humanos , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Microambiente Tumoral/inmunología , Fenotipo Secretor Asociado a la Senescencia , Proteínas Proto-Oncogénicas c-jun/metabolismo , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Perfilación de la Expresión Génica , Senescencia Celular/genética , Modelos Animales de EnfermedadRESUMEN
Immune cells need to sustain a state of constant alertness over a lifetime. Yet, little is known about the regulatory processes that control the fluent and fragile balance that is called homeostasis. Here we demonstrate that JAK-STAT signaling, beyond its role in immune responses, is a major regulator of immune cell homeostasis. We investigated JAK-STAT-mediated transcription and chromatin accessibility across 12 mouse models, including knockouts of all STAT transcription factors and of the TYK2 kinase. Baseline JAK-STAT signaling was detected in CD8+ T cells and macrophages of unperturbed mice-but abrogated in the knockouts and in unstimulated immune cells deprived of their normal tissue context. We observed diverse gene-regulatory programs, including effects of STAT2 and IRF9 that were independent of STAT1. In summary, our large-scale dataset and integrative analysis of JAK-STAT mutant and wild-type mice uncovered a crucial role of JAK-STAT signaling in unstimulated immune cells, where it contributes to a poised epigenetic and transcriptional state and helps prepare these cells for rapid response to immune stimuli.
Asunto(s)
Homeostasis , Quinasas Janus , Macrófagos , Ratones Noqueados , Factores de Transcripción STAT , Transducción de Señal , Animales , Ratones , Macrófagos/inmunología , Macrófagos/metabolismo , Quinasas Janus/metabolismo , Factores de Transcripción STAT/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT1/genética , Ratones Endogámicos C57BL , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/genética , TYK2 Quinasa/metabolismo , TYK2 Quinasa/genética , Regulación de la Expresión GénicaRESUMEN
Iron is an essential cellular metal that is important for many physiological functions including erythropoiesis and host defense. It is absorbed from the diet in the duodenum and loaded onto transferrin (Tf), the main iron transport protein. Inefficient dietary iron uptake promotes many diseases, but mechanisms regulating iron absorption remain poorly understood. By assessing mice that harbor a macrophage-specific deletion of the tuberous sclerosis complex 2 (Tsc2), a negative regulator of mechanistic target of rapamycin complex 1 (mTORC1), we found that these mice possessed various defects in iron metabolism, including defective steady-state erythropoiesis and a reduced saturation of Tf with iron. This iron deficiency phenotype was associated with an iron import block from the duodenal epithelial cells into the circulation. Activation of mTORC1 in villous duodenal CD68+ macrophages induced serine protease expression and promoted local degradation of Tf, whereas the depletion of macrophages in mice increased Tf levels. Inhibition of mTORC1 with everolimus or serine protease activity with nafamostat restored Tf levels and Tf saturation in the Tsc2-deficient mice. Physiologically, Tf levels were regulated in the duodenum during the prandial process and Citrobacter rodentium infection. These data suggest that duodenal macrophages determine iron transfer to the circulation by controlling Tf availability in the lamina propria villi.
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Hierro de la Dieta , Transferrina , Ratones , Animales , Transferrina/metabolismo , Hierro de la Dieta/metabolismo , Hierro/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Dieta , Duodeno/metabolismo , Receptores de Transferrina/metabolismoRESUMEN
Tyrosine kinase 2 (TYK2) is a member of the Janus kinase/signal transducer and activator of transcription pathway, which is central in cytokine signaling. Previously, germline TYK2 mutations have been described in two patients developing de novo T-cell acute lymphoblastic leukemias (T-ALL) or precursor B-ALL. The mutations (P760L and G761V) are located within the regulatory pseudokinase domain and lead to constitutive activation of TYK2. We demonstrate the transformation capacity of TYK2 P760L in hematopoietic cell systems including primary bone marrow cells. In vivo engraftment of TYK2 P760L-expressing cell lines led to development of leukemia. A kinase inhibitor screen uncovered that oncogenic TYK2 acts synergistically with the PI3K/AKT/mTOR and CDK4/6 pathways. Accordingly, the TYK2-specific inhibitor deucravacitinib (BMS986165) reduces cell viability of TYK2 P760L-transformed cell models and ex vivo cultured TYK2 P760L-mutated patient- derived xenograft cells most efficiently when combined with mTOR or CDK4/6 inhibitors. Our study thereby pioneers novel treatment options for patients suffering from TYK2-driven acute leukemia.
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Leucemia-Linfoma Linfoblástico de Células T Precursoras , TYK2 Quinasa , Humanos , Línea Celular , Quinasa 4 Dependiente de la Ciclina , Fosfatidilinositol 3-Quinasas , Serina-Treonina Quinasas TOR , TYK2 Quinasa/genética , TYK2 Quinasa/metabolismoRESUMEN
Janus kinase Tyk2 is implicated in cancer immune surveillance, but its role in solid tumors is not well defined. We used Tyk2 knockout mice (Tyk2Δ/Δ) and mice with conditional deletion of Tyk2 in hematopoietic (Tyk2ΔHem) or intestinal epithelial cells (Tyk2ΔIEC) to assess their cell type-specific functions in chemically induced colorectal cancer. All Tyk2-deficient mouse models showed a higher tumor burden after AOM-DSS treatment compared to their corresponding wild-type controls (Tyk2+/+ and Tyk2fl/fl), demonstrating tumor-suppressive functions of Tyk2 in immune cells and epithelial cancer cells. However, specific deletion of Tyk2 in hematopoietic cells or in intestinal epithelial cells was insufficient to accelerate tumor progression, while deletion in both compartments promoted carcinoma formation. RNA-seq and proteomics revealed that tumors of Tyk2Δ/Δ and Tyk2ΔIEC mice were immunoedited in different ways with downregulated and upregulated IFNγ signatures, respectively. Accordingly, the IFNγ-regulated immune checkpoint Ido1 was downregulated in Tyk2Δ/Δ and upregulated in Tyk2ΔIEC tumors, although both showed reduced CD8+ T cell infiltration. These data suggest that Tyk2Δ/Δ tumors are Ido1-independent and poorly immunoedited while Tyk2ΔIEC tumors require Ido1 for immune evasion. Our study shows that Tyk2 prevents Ido1 expression in CRC cells and promotes CRC immune surveillance in the tumor stroma. Both of these Tyk2-dependent mechanisms must work together to prevent CRC progression.
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Colitis , Neoplasias Colorrectales , Animales , Colitis/inducido químicamente , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Quinasas Janus/metabolismo , Ratones , Ratones NoqueadosRESUMEN
Environmental microbial triggers shape the development and functionality of the immune system. Alveolar macrophages (AMs), tissue-resident macrophages of the lungs, are in constant and direct contact with inhaled particles and microbes. Such exposures likely impact AM reactivity to subsequent challenges by immunological imprinting mechanisms referred to as trained immunity. Here, we investigated whether a ubiquitous microbial compound has the potential to induce AM training in vivo. We discovered that intranasal exposure to ambient amounts of lipopolysaccharide (LPS) induced a pronounced AM memory response, characterized by enhanced reactivity upon pneumococcal challenge. Exploring the mechanistic basis of AM training, we identified a critical role of type 1 interferon signaling and found that inhibition of fatty acid oxidation and glutaminolysis significantly attenuated the training effect. Notably, adoptive transfer of trained AMs resulted in increased bacterial loads and tissue damage upon subsequent pneumococcal infection. In contrast, intranasal pre-exposure to LPS promoted bacterial clearance, highlighting the complexity of stimulus-induced immune responses, which likely involve multiple cell types and may depend on the local immunological and metabolic environment. Collectively, our findings demonstrate the profound impact of ambient microbial exposure on pulmonary immune memory and reveal tissue-specific features of trained immunity.
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Interferón Tipo I , Macrófagos Alveolares , Interferón Tipo I/metabolismo , Lipopolisacáridos , Pulmón , Transducción de SeñalRESUMEN
Our understanding of the composition and functions of splenic stromal cells remains incomplete. Here, based on analysis of over 20,000 single cell transcriptomes of splenic fibroblasts, we characterized the phenotypic and functional heterogeneity of these cells in healthy state and during virus infection. We describe eleven transcriptionally distinct fibroblastic cell clusters, reassuring known subsets and revealing yet unascertained heterogeneity amongst fibroblasts occupying diverse splenic niches. We further identify striking differences in innate immune signatures of distinct stromal compartments in vivo. Compared to other fibroblasts and to endothelial cells, Ly6C+ fibroblasts of the red pulp were selectively endowed with enhanced interferon-stimulated gene expression in homeostasis, upon systemic interferon stimulation and during virus infection in vivo. Collectively, we provide an updated map of fibroblastic cell diversity in the spleen that suggests a specialized innate immune function for splenic red pulp fibroblasts.
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Fibroblastos/metabolismo , Infecciones por Herpesviridae/virología , Inmunidad Innata , Transcriptoma , Animales , Femenino , Fibroblastos/inmunología , Homeostasis , Masculino , Ratones , Muromegalovirus/fisiología , Análisis de la Célula Individual , Bazo/inmunología , Bazo/metabolismoRESUMEN
Innate lymphoid cells (ILC) play a significant role in the intestinal immune response and T-bet+ CD127+ group 1 cells (ILC1) have been linked to the pathogenesis of human inflammatory bowel disease (IBD). However, the functional importance of ILC1 in the context of an intact adaptive immune response has been controversial. In this report we demonstrate that induced depletion of T-bet using a Rosa26-Cre-ERT2 model resulted in the loss of intestinal ILC1, pointing to a post-developmental requirement of T-bet expression for these cells. In contrast, neither colonic lamina propria (cLP) ILC2 nor cLP ILC3 abundance were altered upon induced deletion of T-bet. Mechanistically, we report that STAT1 or STAT4 are not required for intestinal ILC1 development and maintenance. Mice with induced deletion of T-bet and subsequent loss of ILC1 were protected from the induction of severe colitis in vivo. Hence, this study provides support for the clinical development of an IBD treatment based on ILC1 depletion via targeting T-bet or its downstream transcriptional targets.
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Mucosa Intestinal/inmunología , Linfocitos/inmunología , Proteínas de Dominio T Box/inmunología , Animales , Citrobacter rodentium , Colitis/inducido químicamente , Colitis/inmunología , Sulfato de Dextran , Infecciones por Enterobacteriaceae/inmunología , Femenino , Inmunidad Innata , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT1/inmunología , Factor de Transcripción STAT4/genética , Factor de Transcripción STAT4/inmunología , Tamoxifeno/farmacología , Trichinella spiralis , Triquinelosis/inmunologíaRESUMEN
Spondyloarthritis (SpA) is a family of inflammatory arthritic diseases, which includes the prototypes of psoriatic arthritis and ankylosing spondylitis. SpA is commonly associated with systemic inflammatory diseases, such as psoriasis and inflammatory bowel disease. Immunological studies, murine models and the genetics of SpA all indicate a pathogenic role for the IL-23/IL-17 axis. Therapeutics targeting the IL-23/IL-17 pathway are successful at providing symptomatic relief, but may not provide complete protection against progression of arthritis. Thus there is still tremendous interest in the discovery of novel therapeutic targets for SpA. Tyrosine kinase 2 (TYK2) is a member of the Janus kinases, which mediate intracellular signaling of cytokines via signal transducer and activator of transcription (STAT) activation. TYK2 plays a crucial role in mediating IL-23 receptor signaling and STAT3 activation. A plethora of natural mutations in and around TYK2 have provided a wealth of data to associate this kinase with autoimmune/autoinflammatory diseases in humans. Induced and natural mutations in murine Tyk2 largely support human data; however, key inter-species differences exist, which means extrapolation of data from murine models to humans needs to be done with caution. Despite these reservations, novel selective TYK2 inhibitors are now proving successful in advanced clinical trials of inflammatory diseases. In this review, we will discuss TYK2 from basic biology to therapeutic targeting, with an emphasis on studies in SpA. Seminal studies uncovering the basic science of TYK2 have provided sound foundations for targeting it in SpA and related inflammatory diseases. TYK2 inhibitors may well be the next blockbuster therapeutic for SpA.
RESUMEN
Lactate is an end point of Warburg-type metabolism found in inflammatory macrophages. Recently, lactate was shown to modify histones of lipopolysaccharide (LPS)-activated macrophages in a time-dependent way and promote the expression of genes linked to tissue repair, including arginase-1 (Arg1). We tested the interrelationships between histone lactylation (Kla) and tissue reparative gene expression and found that Kla was uncoupled from changes in gene expression linked to resolving M2 macrophage activation but correlated with Arg1 expression. LPS-induced Arg1 was instead dependent on autocrine-paracrine interleukin-6 (IL6) production, the IL6 receptor, and Stat3 signal transduction. We found that Kla increases as macrophages prepare to die under inflammatory stress, and Kla was absent in macrophages that cannot generate reactive nitrogen or have defects in diverse macrophage death pathways. Thus, Kla is a consequence rather than a cause of macrophage activation but occurs coincidently with an IL6- and Arg1-dependent metabolic rewiring under inflammatory duress.
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Interleucina-6 , Ácido Láctico , Histonas/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolisacáridos/metabolismo , Activación de Macrófagos , Macrófagos/metabolismoRESUMEN
Inflammatory diseases are frequently treated with Janus kinase (JAK) inhibitors to diminish cytokine signaling. These treatments can lead to inadvertent immune suppression and may increase the risk of viral infection. Tyrosine kinase 2 (TYK2) is a JAK family member required for efficient type I interferon (IFN-α/ß) signaling. We report here that selective TYK2 inhibition preferentially blocked potentially detrimental type I IFN signaling, whereas IFN-λ-mediated responses were largely preserved. In contrast, the clinically used JAK1/2 inhibitor baricitinib was equally potent in blocking IFN-α/ß- or IFN-λ-driven responses. Mechanistically, we showed that epithelial cells did not require TYK2 for IFN-λ-mediated signaling or antiviral protection. TYK2 deficiency diminished IFN-α-induced protection against lethal influenza virus infection in mice but did not impair IFN-λ-mediated antiviral protection. Our findings suggest that selective TYK2 inhibitors used in place of broadly acting JAK1/2 inhibitors may represent a superior treatment option for type I interferonopathies to counteract inflammatory responses while preserving antiviral protection mediated by IFN-λ.
Asunto(s)
Virus de la Influenza A , Interferones/inmunología , Infecciones por Orthomyxoviridae/inmunología , TYK2 Quinasa/antagonistas & inhibidores , Animales , Azetidinas/farmacología , Células Cultivadas , Células Epiteliales/inmunología , Expresión Génica , Compuestos Heterocíclicos/farmacología , Humanos , Inhibidores de las Cinasas Janus/farmacología , Masculino , Ratones Noqueados , Neutrófilos/inmunología , Purinas/farmacología , Pirazoles/farmacología , Sulfonamidas/farmacología , TYK2 Quinasa/genética , TYK2 Quinasa/inmunologíaRESUMEN
Lipocalin 2 (LCN2) is a secreted glycoprotein with roles in multiple biological processes. It contributes to host defense by interference with bacterial iron uptake and exerts immunomodulatory functions in various diseases. Here, we aimed to characterize the function of LCN2 in lung macrophages and dendritic cells (DCs) using Lcn2-/- mice. Transcriptome analysis revealed strong LCN2-related effects in CD103+ DCs during homeostasis, with differential regulation of antigen processing and presentation and antiviral immunity pathways. We next validated the relevance of LCN2 in a mouse model of influenza infection, wherein LCN2 protected from excessive weight loss and improved survival. LCN2-deficiency was associated with enlarged mediastinal lymph nodes and increased lung T cell numbers, indicating a dysregulated immune response to influenza infection. Depletion of CD8+ T cells equalized weight loss between WT and Lcn2-/- mice, proving that LCN2 protects from excessive disease morbidity by dampening CD8+ T cell responses. In vivo T cell chimerism and in vitro T cell proliferation assays indicated that improved antigen processing by CD103+ DCs, rather than T cell intrinsic effects of LCN2, contribute to the exacerbated T cell response. Considering the antibacterial potential of LCN2 and that commensal microbes can modulate antiviral immune responses, we speculated that LCN2 might cause the observed influenza phenotype via the microbiome. Comparing the lung and gut microbiome of WT and Lcn2-/- mice by 16S rRNA gene sequencing, we observed profound effects of LCN2 on gut microbial composition. Interestingly, antibiotic treatment or co-housing of WT and Lcn2-/- mice prior to influenza infection equalized lung CD8+ T cell counts, suggesting that the LCN2-related effects are mediated by the microbiome. In summary, our results highlight a novel regulatory function of LCN2 in the modulation of antiviral immunity.
Asunto(s)
Gripe Humana/inmunología , Lipocalina 2/metabolismo , Microbiota/inmunología , Transcriptoma , Animales , Presentación de Antígeno , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Células Dendríticas/virología , Femenino , Microbioma Gastrointestinal , Homeostasis , Humanos , Inmunidad , Gripe Humana/virología , Lipocalina 2/genética , Pulmón/inmunología , Pulmón/virología , Activación de Linfocitos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Organismos Libres de Patógenos EspecíficosRESUMEN
The non-canonical inflammasome is an emerging crucial player in the development of inflammatory and neurodegenerative diseases. It is activated by direct sensing of cytosolic lipopolysaccharide (LPS) by caspase-11 (CASP11), which then induces pyroptosis, an inflammatory form of regulated cell death. Here, we report that tyrosine kinase 2 (TYK2), a cytokine receptor-associated kinase, is a critical upstream regulator of CASP11. Absence of TYK2 or its kinase activity impairs the transcriptional induction of CASP11 in vitro and in vivo and protects mice from LPS-induced lethality. Lack of TYK2 or its enzymatic activity inhibits macrophage pyroptosis and impairs release of mature IL-1ß and IL-18 specifically in response to intracellular LPS. Deletion of TYK2 in myeloid cells reduces LPS-induced IL-1ß and IL-18 production in vivo, highlighting the importance of these cells in the inflammatory response to LPS. In support of our data generated with genetically engineered mice, pharmacological inhibition of TYK2 reduced LPS-induced upregulation of CASP11 in bone marrow-derived macrophages (BMDMs) and of its homolog CASP5 in human macrophages. Our study provides insights into the regulation of CASP11 in vivo and uncovered a novel link between TYK2 activity and CASP11-dependent inflammation.
Asunto(s)
Caspasas Iniciadoras/metabolismo , Inflamasomas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Piroptosis/efectos de los fármacos , TYK2 Quinasa/farmacología , Animales , Endotoxemia/tratamiento farmacológico , Femenino , Humanos , Inflamasomas/inmunología , Inflamasomas/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Lipopolisacáridos/toxicidad , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Células Mieloides/efectos de los fármacos , Células Mieloides/inmunología , Células Mieloides/metabolismo , Células U937RESUMEN
BACKGROUND AND AIMS: Tyrosine kinase 2 [TYK2] is required for the signalling of key cytokines in the pathogenesis of inflammatory bowel disease [IBD]. We assessed the efficacy of a novel selective TYK2 inhibitor [TYK2i] in experimental colitis, using pharmacological and genetic tools. METHODS: At onset of T cell transfer colitis, RAG1-/- mice received vehicle or TYK2i daily by oral gavage. T cells lacking TYK2 kinase activity [TYK2KE] were used to confirm selectivity of the inhibitor. To this end, RAG1-/- or RAG1-/-TYK2KE animals were transferred with either wild type [WT] or TYK2KE-CD45RBhigh colitogenic T cells. Loss of body weight, endoscopic disease, the disease activity index [DAI], and histopathology scores were recorded. Tissues were analysed ex vivo for lymphocyte populations by flow cytometry. The impact of TYK2 inhibition on human DC-T cell interactions were studied using autologous Revaxis specific T cell assays. RESULTS: TYK2i [70 mg/kg] prevented weight loss and limited endoscopic activity during T cell transfer colitis. TYK2i [70 mg/kg] decreased DAI. Whereas transfer of WT T cells into RAG-/-TYK2KE hosts induced colitis, TYK2KE T cells transferred into RAG1-/-TYK2KErecipients failed to do so. Ex vivo analysis showed a decrease in colon tissue Th1 cells and an increase in Th17 cells upon transfer of TYK2KE-CD45RBhigh cells. In human antigen-triggered T cells, TYK2i displayed reduced Th1 differentiation, similar to murine Th1 cells. CONCLUSIONS: Oral administration of TYK2i, as well as transfer of T cells lacking TYK2 activity, reduced human Th1 differentiation and ameliorated the course of murine T cell transfer colitis. We conclude that TYK2 is a promising drug target for the treatment of IBD.
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Administración Oral , Traslado Adoptivo , Enfermedades Inflamatorias del Intestino/enzimología , Enfermedades Inflamatorias del Intestino/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , TYK2 Quinasa/antagonistas & inhibidores , Animales , Diferenciación Celular/inmunología , Citocinas/inmunología , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Proteínas de Homeodominio , Humanos , Ratones , Transducción de Señal , Células TH1/metabolismoRESUMEN
Natural killer (NK) cells are important components of the innate immune defense against infections and cancers. Signal transducer and activator of transcription 1 (STAT1) is a transcription factor that is essential for NK cell maturation and NK cell-dependent tumor surveillance. Two alternatively spliced isoforms of STAT1 exist: a full-length STAT1α and a C-terminally truncated STAT1ß isoform. Aberrant splicing is frequently observed in cancer cells and several anti-cancer drugs interfere with the cellular splicing machinery. To investigate whether NK cell-mediated tumor surveillance is affected by a switch in STAT1 splicing, we made use of knock-in mice expressing either only the STAT1α (Stat1α/α) or the STAT1ß (Stat1ß/ß ) isoform. NK cells from Stat1α/α mice matured normally and controlled transplanted tumor cells as efficiently as NK cells from wild-type mice. In contrast, NK cells from Stat1ß/ß mice showed impaired maturation and effector functions, albeit less severe than NK cells from mice that completely lack STAT1 (Stat1-/- ). Mechanistically, we show that NK cell maturation requires the presence of STAT1α in the niche rather than in NK cells themselves and that NK cell maturation depends on IFNγ signaling under homeostatic conditions. The impaired NK cell maturation in Stat1ß/ß mice was paralleled by decreased IL-15 receptor alpha (IL-15Rα) surface levels on dendritic cells, macrophages and monocytes. Treatment of Stat1ß/ß mice with exogenous IL-15/IL-15Rα complexes rescued NK cell maturation but not their effector functions. Collectively, our findings provide evidence that STAT1 isoforms are not functionally redundant in regulating NK cell activity and that the absence of STAT1α severely impairs, but does not abolish, NK cell-dependent tumor surveillance.
Asunto(s)
Células Asesinas Naturales/citología , Linfopoyesis/fisiología , Factor de Transcripción STAT1/inmunología , Animales , Trasplante de Médula Ósea , Línea Celular Tumoral , Citotoxicidad Inmunológica , Vigilancia Inmunológica/efectos de los fármacos , Vigilancia Inmunológica/inmunología , Factor 3 de Genes Estimulados por el Interferón/deficiencia , Factor 3 de Genes Estimulados por el Interferón/genética , Factor 3 de Genes Estimulados por el Interferón/inmunología , Interleucina-15/farmacología , Subunidad alfa del Receptor de Interleucina-15 , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Depleción Linfocítica , Tejido Linfoide/citología , Linfoma/inmunología , Linfoma/patología , Linfopoyesis/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Especificidad de Órganos , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Receptores de Interferón/deficiencia , Factor de Transcripción STAT1/deficiencia , Factor de Transcripción STAT1/genética , Organismos Libres de Patógenos Específicos , Bazo/citología , Receptor de Interferón gammaRESUMEN
Polyphosphates are linear polymers and ubiquitous metabolites. Bacterial polyphosphates are long chains of hundreds of phosphate units. Here, we report that mouse survival of peritoneal Escherichia coli sepsis is compromised by long-chain polyphosphates, and improves with bacterial polyphosphatekinase deficiency or neutralization using recombinant exopolyphosphatase. Polyphosphate activities are chain-length dependent, impair pathogen clearance, antagonize phagocyte recruitment, diminish phagocytosis and decrease production of iNOS and cytokines. Macrophages bind and internalize polyphosphates, in which their effects are independent of P2Y1 and RAGE receptors. The M1 polarization driven by E. coli derived LPS is misdirected by polyphosphates in favor of an M2 resembling phenotype. Long-chain polyphosphates modulate the expression of more than 1800 LPS/TLR4-regulated genes in macrophages. This interference includes suppression of hundreds of type I interferon-regulated genes due to lower interferon production and responsiveness, blunted STAT1 phosphorylation and reduced MHCII expression. In conclusion, prokaryotic polyphosphates disturb multiple macrophage functions for evading host immunity.
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Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/microbiología , Escherichia coli/metabolismo , Interacciones Huésped-Patógeno/inmunología , Inmunidad Innata , Polifosfatos/metabolismo , Animales , Presentación de Antígeno/inmunología , Polaridad Celular , Antígenos de Histocompatibilidad Clase II/metabolismo , Interferón Tipo I/metabolismo , Lipopolisacáridos , Macrófagos/inmunología , Macrófagos/microbiología , Ratones Endogámicos C57BL , Células Mieloides/inmunología , Fenotipo , Sepsis/inmunología , Análisis de Supervivencia , Transcriptoma/genéticaRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
Tumors have evolved mechanisms to escape anti-tumor immunosurveillance. They limit humoral and cellular immune activities in the stroma and render tumors resistant to immunotherapy. Sensitizing tumor cells to immune attack is an important strategy to revert immunosuppression. However, the underlying mechanisms of immune escape are still poorly understood. Here we discover Indoleamine-2,3-dioxygenase-1 (IDO1)+ Paneth cells in the stem cell niche of intestinal crypts and tumors, which promoted immune escape of colorectal cancer (CRC). Ido1 expression in Paneth cells was strictly Stat1 dependent. Loss of IDO1+ Paneth cells in murine intestinal adenomas with tumor cell-specific Stat1 deletion had profound effects on the intratumoral immune cell composition. Patient samples and TCGA expression data suggested corresponding cells in human colorectal tumors. Thus, our data uncovered an immune escape mechanism of CRC and identify IDO1+ Paneth cells as a target for immunotherapy.
Asunto(s)
Neoplasias Colorrectales/patología , Tolerancia Inmunológica/inmunología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Neoplasias Intestinales/patología , Células de Paneth/inmunología , Factor de Transcripción STAT1/fisiología , Animales , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Neoplasias Intestinales/inmunología , Neoplasias Intestinales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
Spondyloarthritis (SpA) represents a family of inflammatory diseases of the spine and peripheral joints. Ankylosing spondylitis (AS) is the prototypic form of SpA in which progressive disease can lead to fusion of the spine. Therapeutically, knowledge of type 3 immunity has translated into the development of IL-23- and IL-17A-blocking antibodies for the treatment of SpA. Despite being able to provide symptomatic control, the current biologics do not prevent the fusion of joints in AS patients. Thus, there is an unmet need for disease-modifying drugs. Genetic studies have linked the Janus kinase TYK2 to AS. TYK2 is a mediator of type 3 immunity through intracellular signaling of IL-23. Here, we describe and characterize a potentially novel small-molecule inhibitor of TYK2 that blocked IL-23 signaling in vitro and inhibited disease progression in animal models of SpA. The effect of the inhibitor appears to be TYK2 specific, using TYK2-inactive mice, which further revealed a duality in the induction of IL-17A and IL-22 by IL-23. Specifically, IL-22 production was TYK2/JAK2/STAT3 dependent, while IL-17A was mostly JAK2 dependent. Finally, we examined the effects of AS-associated TYK2 SNPs on TYK2 expression and function and correlated them with AS disease progression. This work provides evidence that TYK2 inhibitors have great potential as an orally delivered therapeutic for SpA.