RESUMEN
Most tissue-resident macrophage populations develop during embryogenesis, self-renew in the steady state and expand during type 2 immunity. Whether shared mechanisms regulate the proliferation of macrophages in homeostasis and disease is unclear. Here we found that the transcription factor Bhlhe40 was required in a cell-intrinsic manner for the self-renewal and maintenance of large peritoneal macrophages (LPMs), but not that of other tissue-resident macrophages. Bhlhe40 was necessary for the proliferation, but not the polarization, of LPMs in response to the cytokine IL-4. During infection with the helminth Heligmosomoides polygyrus bakeri, Bhlhe40 was required for cell cycling of LPMs. Bhlhe40 repressed the expression of genes encoding the transcription factors c-Maf and Mafb and directly promoted expression of transcripts encoding cell cycle-related proteins to enable the proliferation of LPMs. In LPMs, Bhlhe40 bound to genomic sites co-bound by the macrophage lineage-determining factor PU.1 and to unique sites, including Maf and loci encoding cell-cycle-related proteins. Our findings demonstrate a tissue-specific control mechanism that regulates the proliferation of resident macrophages in homeostasis and type 2 immunity.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteínas de Homeodominio/genética , Homeostasis/genética , Homeostasis/inmunología , Inmunidad/genética , Macrófagos/inmunología , Macrófagos/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Biomarcadores , Ciclo Celular/genética , Ciclo Celular/inmunología , Proliferación Celular , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Técnicas de Inactivación de Genes , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Proteínas de Homeodominio/metabolismo , Inmunofenotipificación , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Ratones , Ratones Transgénicos , Monocitos/inmunología , Monocitos/metabolismo , Especificidad de Órganos/genética , Especificidad de Órganos/inmunología , TranscriptomaRESUMEN
Activated effector T (TE) cells augment anabolic pathways of metabolism, such as aerobic glycolysis, while memory T (TM) cells engage catabolic pathways, like fatty acid oxidation (FAO). However, signals that drive these differences remain unclear. Mitochondria are metabolic organelles that actively transform their ultrastructure. Therefore, we questioned whether mitochondrial dynamics controls T cell metabolism. We show that TE cells have punctate mitochondria, while TM cells maintain fused networks. The fusion protein Opa1 is required for TM, but not TE cells after infection, and enforcing fusion in TE cells imposes TM cell characteristics and enhances antitumor function. Our data suggest that, by altering cristae morphology, fusion in TM cells configures electron transport chain (ETC) complex associations favoring oxidative phosphorylation (OXPHOS) and FAO, while fission in TE cells leads to cristae expansion, reducing ETC efficiency and promoting aerobic glycolysis. Thus, mitochondrial remodeling is a signaling mechanism that instructs T cell metabolic programming.
Asunto(s)
Dinámicas Mitocondriales , Linfocitos T/citología , Linfocitos T/metabolismo , Animales , Diferenciación Celular , Transporte de Electrón , Ácidos Grasos/metabolismo , GTP Fosfohidrolasas/metabolismo , Glucólisis , Humanos , Memoria Inmunológica , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , Transducción de Señal , Linfocitos T/inmunologíaRESUMEN
Tissue-resident memory CD8+ T (Trm) cells share core residency gene programs with tumor-infiltrating lymphocytes (TILs). However, the transcriptional, metabolic, and epigenetic regulation of Trm cell and TIL development and function is largely undefined. Here, we found that the transcription factor Bhlhe40 was specifically required for Trm cell and TIL development and polyfunctionality. Local PD-1 signaling inhibited TIL Bhlhe40 expression, and Bhlhe40 was critical for TIL reinvigoration following anti-PD-L1 blockade. Mechanistically, Bhlhe40 sustained Trm cell and TIL mitochondrial fitness and a functional epigenetic state. Building on these findings, we identified an epigenetic and metabolic regimen that promoted Trm cell and TIL gene signatures associated with tissue residency and polyfunctionality. This regimen empowered the anti-tumor activity of CD8+ T cells and possessed therapeutic potential even at an advanced tumor stage in mouse models. Our results provide mechanistic insights into the local regulation of Trm cell and TIL function.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Linfocitos T CD8-positivos/inmunología , Proteínas de Homeodominio/inmunología , Mitocondrias/inmunología , Animales , Epigénesis Genética/inmunología , Regulación de la Expresión Génica/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Ratones , Ratones Endogámicos C57BL , Receptor de Muerte Celular Programada 1/inmunologíaRESUMEN
Although the transcription factor c-Myc is essential for the establishment of a metabolically active and proliferative state in T cells after priming, its expression is transient. It remains unknown how T cell activation is maintained after c-Myc expression is downregulated. Here we identified AP4 as the transcription factor that was induced by c-Myc and sustained activation of antigen-specific CD8+ T cells. Despite normal priming, AP4-deficient CD8+ T cells failed to continue transcription of a broad range of c-Myc-dependent targets. Mice lacking AP4 specifically in CD8+ T cells showed enhanced susceptibility to infection with West Nile virus. Genome-wide analysis suggested that many activation-induced genes encoding molecules involved in metabolism were shared targets of c-Myc and AP4. Thus, AP4 maintains c-Myc-initiated cellular activation programs in CD8+ T cells to control microbial infection.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Activación de Linfocitos/inmunología , Proteínas Proto-Oncogénicas c-myc/inmunología , Factores de Transcripción/inmunología , Animales , Ratones , Fiebre del Nilo Occidental/inmunologíaRESUMEN
In response to acute infection, naive CD4+ T cells primarily differentiate into T helper 1 (Th1) or T follicular helper (Tfh) cells that play critical roles in orchestrating cellular or humoral arms of immunity, respectively. However, despite the well established role of T-bet and BCL-6 in driving Th1 and Tfh cell lineage commitment, respectively, whether additional transcriptional circuits also underlie the fate bifurcation of Th1 and Tfh cell subsets is not fully understood. In this article, we study how the transcriptional regulator Bhlhe40 dictates the Th1/Tfh differentiation axis in mice. CD4+ T cell-specific deletion of Bhlhe40 abrogates Th1 but augments Tfh differentiation. We also assessed an increase in germinal center B cells and Ab production, suggesting that deletion of Bhlhe40 in CD4+ T cells not only alters Tfh differentiation but also their capacity to provide help to B cells. To identify molecular mechanisms by which Bhlhe40 regulates Th1 versus Tfh lineage choice, we first performed epigenetic profiling in the virus specific Th1 and Tfh cells following LCMV infection, which revealed distinct promoter and enhancer activities between the two helper cell lineages. Furthermore, we identified that Bhlhe40 directly binds to cis-regulatory elements of Th1-related genes such as Tbx21 and Cxcr6 to activate their expression while simultaneously binding to regions of Tfh-related genes such as Bcl6 and Cxcr5 to repress their expression. Collectively, our data suggest that Bhlhe40 functions as a transcription activator to promote Th1 cell differentiation and a transcription repressor to suppress Tfh cell differentiation.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Diferenciación Celular , Células T Auxiliares Foliculares , Células TH1 , Animales , Ratones , Diferenciación Celular/inmunología , Diferenciación Celular/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Células T Auxiliares Foliculares/inmunología , Células TH1/inmunología , Ratones Noqueados , Ratones Endogámicos C57BL , Linfocitos B/inmunología , Coriomeningitis Linfocítica/inmunología , Coriomeningitis Linfocítica/virología , Centro Germinal/inmunología , Proteínas Proto-Oncogénicas c-bcl-6/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Virus de la Coriomeningitis Linfocítica/inmunología , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Proteínas de HomeodominioRESUMEN
Better understanding of the host responses to Mycobacterium tuberculosis infections is required to prevent tuberculosis and develop new therapeutic interventions. The host transcription factor BHLHE40 is essential for controlling M. tuberculosis infection, in part by repressing Il10 expression, where excess IL-10 contributes to the early susceptibility of Bhlhe40-/- mice to M. tuberculosis infection. Deletion of Bhlhe40 in lung macrophages and dendritic cells is sufficient to increase the susceptibility of mice to M. tuberculosis infection, but how BHLHE40 impacts macrophage and dendritic cell responses to M. tuberculosis is unknown. In this study, we report that BHLHE40 is required in myeloid cells exposed to GM-CSF, an abundant cytokine in the lung, to promote the expression of genes associated with a proinflammatory state and better control of M. tuberculosis infection. Loss of Bhlhe40 expression in murine bone marrow-derived myeloid cells cultured in the presence of GM-CSF results in lower levels of proinflammatory associated signaling molecules IL-1ß, IL-6, IL-12, TNF-α, inducible NO synthase, IL-2, KC, and RANTES, as well as higher levels of the anti-inflammatory-associated molecules MCP-1 and IL-10 following exposure to heat-killed M. tuberculosis. Deletion of Il10 in Bhlhe40-/- myeloid cells restored some, but not all, proinflammatory signals, demonstrating that BHLHE40 promotes proinflammatory responses via both IL-10-dependent and -independent mechanisms. In addition, we show that macrophages and neutrophils within the lungs of M. tuberculosis-infected Bhlhe40-/- mice exhibit defects in inducible NO synthase production compared with infected wild-type mice, supporting that BHLHE40 promotes proinflammatory responses in innate immune cells, which may contribute to the essential role for BHLHE40 during M. tuberculosis infection in vivo.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Interleucina-10 , Ratones Noqueados , Células Mieloides , Animales , Ratones , Interleucina-10/inmunología , Interleucina-10/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Células Mieloides/inmunología , Mycobacterium tuberculosis/inmunología , Macrófagos/inmunología , Proteínas de Homeodominio/genética , Ratones Endogámicos C57BL , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Células Dendríticas/inmunología , Pulmón/inmunología , Tuberculosis/inmunología , Polaridad Celular , Células CultivadasRESUMEN
Ubiquitination is a major mechanism that regulates numerous cellular processes, including autophagy, DNA damage signaling, and inflammation. While hundreds of ubiquitin ligases exist to conjugate ubiquitin onto substrates, approximately 100 deubiquitinases are encoded by the human genome. Thus, deubiquitinases are likely regulated by unidentified mechanisms to target distinct substrates and cellular functions. Here, we demonstrate that the deubiquitinase OTUD4, which nominally encodes a K48-specific deubiquitinase, is phosphorylated near its catalytic domain, activating a latent K63-specific deubiquitinase. Besides phosphorylation, this latter activity requires an adjacent ubiquitin-interacting motif, which increases the affinity of OTUD4 for K63-linked chains. We reveal the Toll-like receptor (TLR)-associated factor MyD88 as a target of this K63 deubiquitinase activity. Consequently, TLR-mediated activation of NF-κB is negatively regulated by OTUD4, and macrophages from Otud4-/- mice exhibit increased inflammatory signaling upon TLR stimulation. Our results reveal insights into how a deubiquitinase may modulate diverse processes through post-translational modification.
Asunto(s)
Factor 88 de Diferenciación Mieloide/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Animales , Enzimas Desubicuitinizantes/genética , Enzimas Desubicuitinizantes/metabolismo , Células HEK293 , Humanos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Fosforilación , Proteolisis , Transducción de Señal , Receptores Toll-Like , Ubiquitina/metabolismo , UbiquitinaciónRESUMEN
NK cells represent a cellular component of the mammalian innate immune system, and they mount rapid responses against viral infection, including the secretion of the potent antiviral effector cytokine IFN-γ. Following mouse CMV infection, Bhlhe40 was the most highly induced transcription factor in NK cells among the basic helix-loop-helix family. Bhlhe40 upregulation in NK cells depended upon IL-12 and IL-18 signals, with the promoter of Bhlhe40 enriched for STAT4 and the permissive histone H3K4me3, and with STAT4-deficient NK cells showing an impairment of Bhlhe40 induction and diminished H3K4me3. Transcriptomic and protein analysis of Bhlhe40-deficient NK cells revealed a defect in IFN-γ production during mouse CMV infection, resulting in diminished protective immunity following viral challenge. Finally, we provide evidence that Bhlhe40 directly promotes IFN-γ by binding throughout the Ifng loci in activated NK cells. Thus, our study reveals how STAT4-mediated control of Bhlhe40 drives protective IFN-γ secretion by NK cells during viral infection.
Asunto(s)
Infecciones por Citomegalovirus , Células Asesinas Naturales , Ratones , Animales , Interferón gamma , Citocinas/metabolismo , Interleucina-12/metabolismo , Infecciones por Citomegalovirus/metabolismo , Factor de Transcripción STAT4/metabolismo , Mamíferos/metabolismo , Proteínas de Homeodominio/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismoRESUMEN
Platelet transfusion and transplantation of allogeneic stem cells and solid organs are life-saving therapies. Unwanted alloantibodies to nonself human leukocyte antigens (HLAs) on donor cells increase the immunological barrier to these therapies and are important causes of platelet transfusion refractoriness and graft rejection. Although the specificities of anti-HLA antibodies can be determined at the allelic level, traditional treatments for antibody-mediated rejection nonselectively suppress humoral immunity and are not universally successful. We designed HLA-Fc fusion proteins with a bivalent targeting module derived from extracellular domains of HLA and an Fc effector module from mouse IgG2a. We found that HLA-Fc with A2 (A2Fc) and B7 (B7Fc) antigens lowered HLA-A2- and HLA-B7-specific reactivities, respectively, in sera from HLA-sensitized patients. A2Fc and B7Fc bound to B-cell hybridomas bearing surface immunoglobulins with cognate specificities and triggered antigen-specific and Fc-dependent cytotoxicity in vitro. In immunodeficient mice carrying HLA-A2-specific hybridoma cells, A2Fc treatment lowered circulating anti-HLA-A2 levels, abolished the outgrowth of hybridoma cells, and prolonged survival compared with control groups. In an in vivo anti-HLA-A2-mediated platelet transfusion refractoriness model, A2Fc treatment mitigated refractoriness. These results support HLA-Fc being a novel strategy for antigen-specific humoral suppression to improve transfusion and transplantation outcomes. With the long-term goal of targeting HLA-specific memory B cells for desensitization, further studies of HLA-Fc's efficacy in immune-competent animal models are warranted.
Asunto(s)
Isoanticuerpos , Trombocitopenia , Humanos , Ratones , Animales , Antígeno HLA-B7 , Antígenos HLA , Rechazo de Injerto , Suero Antilinfocítico , Antígeno HLA-A2 , Células Productoras de Anticuerpos , Inmunoglobulina G , Receptores de Antígenos de Linfocitos BRESUMEN
The local microenvironment shapes macrophage differentiation in each tissue. We hypothesized that in the peritoneum, local factors in addition to retinoic acid can support GATA6-driven differentiation and function of peritoneal large cavity macrophages (LCMs). We found that soluble proteins produced by mesothelial cells lining the peritoneal cavity maintained GATA6 expression in cultured LCMs. Analysis of global gene expression of isolated mesothelial cells highlighted mesothelin (Msln) and its binding partner mucin 16 (Muc16) as candidate secreted ligands that potentially regulate GATA6 expression in peritoneal LCMs. Mice deficient for either of these molecules showed diminished GATA6 expression in peritoneal and pleural LCMs that was most prominent in aged mice. The more robust phenotype in older mice suggested that monocyte-derived macrophages were the target of Msln and Muc16. Cell transfer and bone marrow chimera experiments supported this hypothesis. We found that lethally irradiated Msln-/- and Muc16-/- mice reconstituted with wild-type bone marrow had lower levels of GATA6 expression in peritoneal and pleural LCMs. Similarly, during the resolution of zymosan-induced inflammation, repopulated peritoneal LCMs lacking expression of Msln or Muc16 expressed diminished GATA6. These data support a role for mesothelial cell-produced Msln and Muc16 in local macrophage differentiation within large cavity spaces such as the peritoneum. The effect appears to be most prominent on monocyte-derived macrophages that enter into this location as the host ages and also in response to infection.
Asunto(s)
Macrófagos Peritoneales , Macrófagos , Ratones , Animales , Cavidad Peritoneal , Peritoneo , EpitelioRESUMEN
Natalizumab, a humanized monoclonal antibody (mAb) against α4-integrin, reduces the number of dendritic cells (DC) in cerebral perivascular spaces in multiple sclerosis (MS). Selective deletion of α4-integrin in CD11c+ cells should curtail their migration to the central nervous system (CNS) and ameliorate experimental autoimmune encephalomyelitis (EAE). We generated CD11c.Cre+/-ITGA4fl/fl C57BL/6 mice to selectively delete α4-integrin in CD11c+ cells. Active immunization and adoptive transfer EAE models were employed and compared with WT controls. Multiparameter flow cytometry was utilized to immunophenotype leukocyte subsets. Single-cell RNA sequencing was used to profile individual cells. α4-Integrin expression by CD11c+ cells was significantly reduced in primary and secondary lymphoid organs in CD11c.Cre+/-ITGA4fl/fl mice. In active EAE, a delayed disease onset was observed in CD11c.Cre+/-ITGA4fl/fl mice, during which CD11c+CD88+ cells were sequestered in the blood. Upon clinical EAE onset, CD11c+CD88+ cells appeared in the CNS and expressed CD317+ In adoptive transfer experiments, CD11c.Cre+/-ITGA4fl/fl mice had ameliorated clinical disease phenotype associated with significantly diminished numbers of CNS CD11c+CD88+CD317+ cells. In human cerebrospinal fluid from subjects with neuroinflammation, microglia-like cells display coincident expression of ITGAX (CD11c), C5AR1 (CD88), and BST2 (CD317). In mice, we show that only activated, but not naïve microglia expressed CD11c, CD88, and CD317. Finally, anti-CD317 treatment prior to clinical EAE substantially enhanced recovery in mice.
Asunto(s)
Antígenos CD/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Integrina alfa4/metabolismo , Células Mieloides/metabolismo , Animales , Presentación de Antígeno , Células Cultivadas , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Femenino , Humanos , Masculino , Ratones , Microglía/metabolismoRESUMEN
The basic helix-loop-helix transcription factor (TF) Bhlhe40 is emerging as a key regulator of immunity during infection, autoimmunity, and inflammatory conditions. We describe the roles of Bhlhe40 in the circulating and tissue-resident arms of the immune system, with emphasis on recent work on the regulation of cytokine production and proliferation. We explore the mechanisms behind these functions in mouse models and human cells, including interactions with other TFs, and propose that Bhlhe40 is a central mediator of both inflammation and pathogen control, as well as a crucial regulator of a growing number of tissue-resident leukocyte populations. Finally, we suggest areas for further study that may advance our understanding of immunity and disease.
Asunto(s)
Autoinmunidad , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Inmunidad , Factores de Transcripción , Animales , Autoinmunidad/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Regulación de la Expresión Génica , Proteínas de Homeodominio/inmunología , Humanos , Inmunidad/genética , Factores de Transcripción/genéticaRESUMEN
Gastrointestinal (GI) tract involvement is the major cause of morbidity and mortality in acute graft-versus-host disease (GVHD), and pathological damage is largely attributable to inflammatory cytokine production. Recently, granulocyte-macrophage colony stimulating factor (GM-CSF) has been identified as a cytokine that mediates inflammation in the GI tract, but the transcriptional program that governs GM-CSF production and the mechanism by which GM-CSF links adaptive to innate immunity within this tissue site have not been defined. In the current study, we identified Bhlhe40 as a key transcriptional regulator that governs GM-CSF production by CD4+ T cells and mediates pathological damage in the GI tract during GVHD. In addition, we observed that GM-CSF was not regulated by either interleukin 6 (IL-6) or IL-23, which are both potent inducers of GVHD-induced colonic pathology, indicating that GM-CSF constitutes a nonredundant inflammatory pathway in the GI tract. Mechanistically, GM-CSF had no adverse effect on regulatory T-cell reconstitution, but linked adaptive to innate immunity by enhancing the activation of donor-derived dendritic cells in the colon and subsequent accumulation of these cells in the mLNs. In addition, GM-CSF promoted indirect alloantigen presentation, resulting in the accumulation of donor-derived T cells with a proinflammatory cytokine phenotype in the colon. Thus, Bhlhe40+ GM-CSF+ CD4+ T cells constitute a colitogenic T-cell population that promotes indirect alloantigen presentation and pathological damage within the GI tract, positioning GM-CSF as a key regulator of GVHD in the colon and a potential therapeutic target for amelioration of this disease.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Antígenos CD4/inmunología , Linfocitos T CD4-Positivos/patología , Enfermedad Injerto contra Huésped/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Proteínas de Homeodominio/inmunología , Isoantígenos/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Colon/inmunología , Colon/patología , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/patología , Enfermedad Injerto contra Huésped/inmunología , Ratones Endogámicos C57BLRESUMEN
The transcription factor BHLHE40 is an emerging regulator of the immune system. Recent studies suggest that BHLHE40 regulates type 2 immunity, but this has not been demonstrated in vivo. We found that BHLHE40 is required in T cells for a protective TH2 cell response in mice infected with the helminth Heligmosomoides polygyrus bakeri H. polygyrus elicited changes in gene and cytokine expression by lamina propria CD4+ T cells, many of which were BHLHE40 dependent, including production of the common ß (CSF2RB) chain family cytokines GM-CSF and IL-5. In contrast to deficiency in GM-CSF or IL-5 alone, loss of both GM-CSF and IL-5 signaling impaired protection against H. polygyrus Overall, we show that BHLHE40 regulates the TH2 cell transcriptional program during helminth infection to support normal expression of Csf2, Il5, and other genes required for protection and reveal unexpected redundancy of common ß chain-dependent cytokines previously thought to possess substantially divergent functions.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Proteínas de Homeodominio/metabolismo , Interleucina-5/metabolismo , Nematospiroides dubius/inmunología , Infecciones por Strongylida/inmunología , Células Th2/inmunología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Subunidad beta Común de los Receptores de Citocinas/genética , Subunidad beta Común de los Receptores de Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Proteínas de Homeodominio/genética , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/genética , Interleucina-5/antagonistas & inhibidores , Interleucina-5/genética , Interleucina-5/inmunología , Ratones , Ratones Noqueados , Membrana Mucosa/citología , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Infecciones por Strongylida/parasitología , Células Th2/efectos de los fármacos , Transcripción Genética/inmunologíaRESUMEN
Pro-inflammatory cytokinemia is a hallmark of highly pathogenic H5N1 influenza virus (IAV) disease yet little is known about the role of host proteins in modulating a pathogenic innate immune response. The host Interferon Induced Protein 35 (Ifi35) has been implicated in increased susceptibility to H5N1-IAV infection. Here, we show that Ifi35 deficiency leads to reduced morbidity in mouse models of highly pathogenic H5N1- and pandemic H1N1-IAV infection. Reduced weight loss in Ifi35-/- mice following H5N1-IAV challenge was associated with reduced cellular infiltration and decreased production of specific cytokines and chemokines including IL-12p40. Expression of Ifi35 by the hematopoietic cell compartment in bone-marrow chimeric mice contributed to increased immune cell recruitment and IL-12p40 production. In addition, Ifi35 deficient primary macrophages produce less IL-12p40 following TLR-3, TLR-4, and TLR-7 stimulation in vitro. Decreased levels of IL-12p40 and its homodimer, IL-12p80, were found in bronchoalveolar lavage fluid of H5N1-IAV infected Ifi35 deficient mice. Specific antibody blockade of IL-12p80 ameliorated weight loss and reduced cellular infiltration following H5N1-IAV infection in wild-type mice; suggesting that increased levels of IL-12p80 alters the immune response to promote inflammation and IAV disease. These data establish a role for Ifi35 in modulating cytokine production and exacerbating inflammation during IAV infection.
Asunto(s)
Inmunidad Innata/inmunología , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Subunidad p40 de la Interleucina-12/metabolismo , Péptidos y Proteínas de Señalización Intracelular/fisiología , Infecciones por Orthomyxoviridae/virología , Neumonía/virología , Animales , Quimiocinas/metabolismo , Citocinas/metabolismo , Dimerización , Femenino , Subunidad p40 de la Interleucina-12/química , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/patología , Neumonía/metabolismo , Neumonía/patologíaRESUMEN
Skin-resident dendritic cells (DCs) are well positioned to encounter cutaneous pathogens and are required for the initiation of adaptive immune responses. There are at least three subsets of skin DC- Langerhans cells (LC), Langerin(+) dermal DCs (dDCs), and classic dDCs. Whether these subsets have distinct or redundant function in vivo is poorly understood. Using a Candida albicans skin infection model, we have shown that direct presentation of antigen by LC is necessary and sufficient for the generation of antigen-specific T helper-17 (Th17) cells but not for the generation of cytotoxic lymphocytes (CTLs). In contrast, Langerin(+) dDCs are required for the generation of antigen specific CTL and Th1 cells. Langerin(+) dDCs also inhibited the ability of LCs and classic DCs to promote Th17 cell responses. This work demonstrates that skin-resident DC subsets promote distinct and opposing antigen-specific responses.
Asunto(s)
Candida albicans/inmunología , Candidiasis/inmunología , Células Dendríticas/metabolismo , Subgrupos de Linfocitos T/metabolismo , Células Th17/metabolismo , Traslado Adoptivo , Animales , Antígenos Bacterianos/inmunología , Antígenos de Superficie/biosíntesis , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Candida albicans/patogenicidad , Candidiasis/microbiología , Candidiasis/patología , Células Cultivadas , Reactividad Cruzada , Células Dendríticas/inmunología , Células Dendríticas/microbiología , Células Dendríticas/patología , Modelos Animales de Enfermedad , Lectinas Tipo C/biosíntesis , Activación de Linfocitos , Lectinas de Unión a Manosa/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Proteínas Represoras/genética , Piel/microbiología , Piel/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/microbiología , Subgrupos de Linfocitos T/parasitología , Células Th17/inmunología , Células Th17/microbiología , Células Th17/patologíaRESUMEN
CD8α(+) dendritic cells (DCs) prime cytotoxic T lymphocytes during viral infections and produce interleukin-12 in response to pathogens. Although the loss of CD8α(+) DCs in Batf3(-/-) mice increases their susceptibility to several pathogens, we observed that Batf3(-/-) mice exhibited enhanced resistance to the intracellular bacterium Listeria monocytogenes. In wild-type mice, Listeria organisms, initially located in the splenic marginal zone, migrated to the periarteriolar lymphoid sheath (PALS) where they grew exponentially and induced widespread lymphocyte apoptosis. In Batf3(-/-) mice, however, Listeria organisms remain trapped in the marginal zone, failed to traffic into the PALS, and were rapidly cleared by phagocytes. In addition, Batf3(-/-) mice, which lacked the normal population of hepatic CD103(+) peripheral DCs, also showed protection from liver infection. These results suggest that Batf3-dependent CD8α(+) and CD103(+) DCs provide initial cellular entry points within the reticuloendothelial system by which Listeria establishes productive infection.
Asunto(s)
Células Dendríticas/metabolismo , Listeria monocytogenes/fisiología , Listeriosis/inmunología , Ganglios Linfáticos/metabolismo , Bazo/metabolismo , Animales , Antígenos CD/biosíntesis , Apoptosis/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Antígenos CD8/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/microbiología , Células Dendríticas/patología , Inmunidad Innata/genética , Cadenas alfa de Integrinas/biosíntesis , Listeria monocytogenes/patogenicidad , Listeriosis/microbiología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/microbiología , Ganglios Linfáticos/patología , Linfocitos/patología , Ratones , Ratones Endogámicos , Ratones Noqueados , Fagocitosis/genética , Proteínas Represoras/genética , Bazo/inmunología , Bazo/microbiología , Bazo/patología , VirulenciaRESUMEN
The transcription factors c-Myc and N-Myc--encoded by Myc and Mycn, respectively--regulate cellular growth and are required for embryonic development. A third paralogue, Mycl1, is dispensable for normal embryonic development but its biological function has remained unclear. To examine the in vivo function of Mycl1 in mice, we generated an inactivating Mycl1(gfp) allele that also reports Mycl1 expression. We find that Mycl1 is selectively expressed in dendritic cells (DCs) of the immune system and controlled by IRF8, and that during DC development, Mycl1 expression is initiated in the common DC progenitor concurrent with reduction in c-Myc expression. Mature DCs lack expression of c-Myc and N-Myc but maintain L-Myc expression even in the presence of inflammatory signals such as granulocyte-macrophage colony-stimulating factor. All DC subsets develop in Mycl1-deficient mice, but some subsets such as migratory CD103(+) conventional DCs in the lung and liver are greatly reduced at steady state. Importantly, loss of L-Myc by DCs causes a significant decrease in in vivo T-cell priming during infection by Listeria monocytogenes and vesicular stomatitis virus. The replacement of c-Myc by L-Myc in immature DCs may provide for Myc transcriptional activity in the setting of inflammation that is required for optimal T-cell priming.
Asunto(s)
Reactividad Cruzada/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Regulación de la Expresión Génica , Proteínas Proto-Oncogénicas c-myc/metabolismo , Linfocitos T/inmunología , Animales , Antígenos CD/metabolismo , División Celular , Células Dendríticas/citología , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Cadenas alfa de Integrinas/metabolismo , Factores Reguladores del Interferón/metabolismo , Listeria monocytogenes/inmunología , Hígado/citología , Hígado/inmunología , Pulmón/citología , Pulmón/inmunología , Masculino , Ratones , Proteínas Proto-Oncogénicas c-myc/deficiencia , Transcripción Genética , Vesiculovirus/inmunologíaRESUMEN
Multiple sclerosis (MS), and its animal model experimental autoimmune encephalomyelitis, are neuroinflammatory diseases driven by autoreactive pathogenic TH cells that elicit demyelination and axonal damage. How TH cells acquire pathogenicity and communicate with myeloid cells and cells of the CNS remain unclear. IL-1ß is recognized to play an important role in experimental autoimmune encephalomyelitis (EAE) and perhaps MS. Clinical EAE is significantly attenuated in IL-1R-deficient and IL-1ß-deficient mice, and IL-1ß is found in the blood, cerebrospinal fluid, and CNS lesions of MS patients. In this article, we focus on new reports that elucidate the cellular sources of IL-1ß and its actions during EAE, in both lymphoid tissues and within the CNS. Several immune cell types serve as critical producers of IL-1ß during EAE, with this cytokine inducing response in both hematopoietic and nonhematopoietic cells. These findings from the EAE model should inspire efforts toward investigating the therapeutic potential of IL-1 blockade in MS.