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Epstein-Barr virus (EBV) is deemed a necessary, yet insufficient factor in the development of multiple sclerosis (MS). In this study, myelin basic protein-specific transgenic T cell receptor mice were infected with murid gammaherpesvirus 68 virus (MHV68), an EBV-like virus that infects mice, resulting in the onset neurological deficits at a significantly higher frequency than influenza or mock-infected mice. MHV68 infected mice exhibited signs including optic neuritis and ataxia which are frequently observed in MS patients but not in experimental autoimmune encephalomyelitis mice. MHV68-infected mice exhibited increased focal immune cell infiltration in the central nervous system. Single cell RNA sequencing identified the emergence of a population of B cells that express genes associated with antigen presentation and costimulation, indicating that gammaherpesvirus infection drives a distinct, pro-inflammatory transcriptional program in B cells that may promote autoreactive T cell responses in MS.
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Linfócitos B , Modelos Animais de Doenças , Camundongos Transgênicos , Esclerose Múltipla , Animais , Esclerose Múltipla/imunologia , Esclerose Múltipla/virologia , Camundongos , Linfócitos B/imunologia , Camundongos Endogâmicos C57BL , Rhadinovirus/imunologia , Feminino , Encefalomielite Autoimune Experimental/imunologiaRESUMO
Cutaneous leishmaniasis caused by Leishmania parasites exhibits a wide range of clinical manifestations. Although parasites influence disease severity, cytolytic CD8+ T cell responses mediate disease. Although these responses originate in the lymph node, we found that expression of the cytolytic effector molecule granzyme B was restricted to lesional CD8+ T cells in Leishmania-infected mice, suggesting that local cues within inflamed skin induced cytolytic function. Expression of Blimp-1 (Prdm1), a transcription factor necessary for cytolytic CD8+ T cell differentiation, was driven by hypoxia within the inflamed skin. Hypoxia was further enhanced by the recruitment of neutrophils that consumed oxygen to produce ROS and ultimately increased the hypoxic state and granzyme B expression in CD8+ T cells. Importantly, lesions from patients with cutaneous leishmaniasis exhibited hypoxia transcription signatures that correlated with the presence of neutrophils. Thus, targeting hypoxia-driven signals that support local differentiation of cytolytic CD8+ T cells may improve the prognosis for patients with cutaneous leishmaniasis, as well as for other inflammatory skin diseases in which cytolytic CD8+ T cells contribute to pathogenesis.
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Linfócitos T CD8-Positivos , Leishmaniose Cutânea , Neutrófilos , Fator 1 de Ligação ao Domínio I Regulador Positivo , Animais , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Leishmaniose Cutânea/parasitologia , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/metabolismo , Humanos , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/imunologia , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Granzimas/metabolismo , Granzimas/imunologia , Granzimas/genética , Hipóxia Celular/imunologia , FemininoRESUMO
Antibody-dependent cell-mediated cytotoxicity, mediated by natural killer (NK) cells and antibodies, emerged as a secondary correlate of protection in the RV144 HIV vaccine clinical trial, the only vaccine thus far demonstrating some efficacy in human. Therefore, leveraging NK cells with enhanced cytotoxic effector responses may bolster vaccine induced protection against HIV. Here, we investigated the effect of orally administering indole-3-carbinol (I3C), an aryl hydrocarbon receptor (AHR) agonist, as an adjuvant to an RV144-like vaccine platform in a mouse model. We demonstrate the expansion of KLRG1-expressing NK cells induced by the vaccine together with I3C. This NK cell subset exhibited enhanced vaccine antigen-specific cytotoxic memory-like features. Our study underscores the potential of incorporating I3C as an oral adjuvant to HIV vaccine platforms to enhance antigen-specific (memory-like) cytotoxicity of NK cells against HIV-infected cells. This approach may contribute to enhancing the protective efficacy of HIV preventive vaccines against HIV acquisition.
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In contrast to the "helper" activities of most CD4+ T effector subsets, CD4+ cytotoxic T lymphocytes (CD4-CTLs) perform functions normally associated with CD8+ T and NK cells. Specifically, CD4-CTLs secrete cytotoxic molecules and directly target and kill compromised cells in an MHC class II-restricted fashion. The functions of these cells have been described in diverse immunological contexts, including their ability to provide protection during antiviral and antitumor responses, as well as being implicated in autoimmunity. Despite their significance to human health, the complete mechanisms that govern their programming remain unclear. In this article, we identify the Ikaros zinc finger transcription factor Eos (Ikzf4) as a positive regulator of CD4-CTL differentiation during murine immune responses against influenza virus infection. We find that the frequency of Eos+ cells is elevated in lung CD4-CTL populations and that the cytotoxic gene program is compromised in Eos-deficient CD4+ T cells. Consequently, we observe a reduced frequency and number of lung-residing, influenza virus-responsive CD4-CTLs in the absence of Eos. Mechanistically, we determine that this is due, at least in part, to reduced expression of IL-2 and IL-15 cytokine receptor subunits on the surface of Eos-deficient CD4+ T cells, both of which support the CD4-CTL program. Finally, we find that Aiolos, a related Ikaros family member and known CD4-CTL antagonist, represses Eos expression by antagonizing STAT5-dependent activation of the Ikzf4 promoter. Collectively, our findings reveal a mechanism wherein Eos and Aiolos act in opposition to regulate cytotoxic programming of CD4+ T cells.
Assuntos
Antineoplásicos , Linfócitos T CD4-Positivos , Camundongos , Humanos , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Linfócitos T Citotóxicos , Diferenciação Celular , Citocinas/metabolismo , Antineoplásicos/metabolismoRESUMO
Intestinal intraepithelial lymphocytes (IELs) exhibit prompt innate-like responses to microenvironmental cues and require strict control of effector functions. Here we showed that Aiolos, an Ikaros zinc-finger family member encoded by Ikzf3, acted as a regulator of IEL activation. Ikzf3-/- CD8αα+ IELs had elevated expression of NK receptors, cytotoxic enzymes, cytokines and chemokines. Single-cell RNA sequencing of Ikzf3-/- and Ikzf3+/+ IELs showed an amplified effector machinery in Ikzf3-/- CD8αα+ IELs compared to Ikzf3+/+ counterparts. Ikzf3-/- CD8αα+ IELs had increased responsiveness to interleukin-15, which explained a substantial part, but not all, of the observed phenotypes. Aiolos binding sites were close to those for the transcription factors STAT5 and RUNX, which promote interleukin-15 signaling and cytolytic programs, and Ikzf3 deficiency partially increased chromatin accessibility and histone acetylation in these regions. Ikzf3 deficiency in mice enhanced susceptibility to colitis, underscoring the relevance of Aiolos in regulating the effector function in IELs.
Assuntos
Linfócitos Intraepiteliais , Fatores de Transcrição , Animais , Camundongos , Antígenos CD8/metabolismo , Interleucina-15/metabolismo , Mucosa Intestinal/metabolismo , Linfócitos Intraepiteliais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Cutaneous leishmaniasis caused by Leishmania parasites exhibits a wide range of clinical manifestations. Although parasites influence disease severity, cytolytic CD8 T cell responses mediate disease. While these responses originate in the lymph node, we find that expression of the cytolytic effector molecule granzyme B is restricted to lesional CD8 T cells in Leishmania - infected mice, suggesting that local cues within inflamed skin induce cytolytic function. Expression of Blimp-1 ( Prdm1 ), a transcription factor necessary for cytolytic CD8 T cell differentiation, is driven by hypoxia within the inflamed skin. Hypoxia is further enhanced by the recruitment of neutrophils that consume oxygen to produce reactive oxygen species, ultimately increasing granzyme B expression in CD8 T cells. Importantly, lesions from cutaneous leishmaniasis patients exhibit hypoxia transcription signatures that correlate with the presence of neutrophils. Thus, targeting hypoxia-driven signals that support local differentiation of cytolytic CD8 T cells may improve the prognosis for patients with cutaneous leishmaniasis, as well as other inflammatory skin diseases where cytolytic CD8 T cells contribute to pathogenesis.
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Treatment of osteoporosis commonly diminishes osteoclast number which suppresses bone formation thus compromising fracture prevention. Bone formation is not suppressed, however, when bone degradation is reduced by retarding osteoclast functional resorptive capacity, rather than differentiation. We find deletion of deubiquitinase, BRCA1-associated protein 1 (Bap1), in myeloid cells (Bap1∆LysM), arrests osteoclast function but not formation. Bap1∆LysM osteoclasts fail to organize their cytoskeleton which is essential for bone degradation consequently increasing bone mass in both male and female mice. The deubiquitinase activity of BAP1 modifies osteoclast function by metabolic reprogramming. Bap1 deficient osteoclast upregulate the cystine transporter, Slc7a11, by enhanced H2Aub occupancy of its promoter. SLC7A11 controls cellular reactive oxygen species levels and redirects the mitochondrial metabolites away from the tricarboxylic acid cycle, both being necessary for osteoclast function. Thus, in osteoclasts BAP1 appears to regulate the epigenetic-metabolic axis and is a potential target to reduce bone degradation while maintaining osteogenesis in osteoporotic patients.
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Osteoclastos , Osteogênese , Animais , Feminino , Humanos , Masculino , Camundongos , Densidade Óssea , Ciclo do Ácido Cítrico , Enzimas Desubiquitinantes , Osteogênese/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genéticaRESUMO
During intracellular infection, T follicular helper (TFH) and T helper 1 (TH1) cells promote humoral and cell-mediated responses, respectively. Another subset, CD4-cytotoxic T lymphocytes (CD4-CTLs), eliminate infected cells via functions typically associated with CD8+ T cells. The mechanisms underlying differentiation of these populations are incompletely understood. Here, we identify the transcription factor Aiolos as a reciprocal regulator of TFH and CD4-CTL programming. We find that Aiolos deficiency results in downregulation of key TFH transcription factors, and consequently reduced TFH differentiation and antibody production, during influenza virus infection. Conversely, CD4-CTL programming is elevated, including enhanced Eomes and cytolytic molecule expression. We further demonstrate that Aiolos deficiency allows for enhanced IL-2 sensitivity and increased STAT5 association with CD4-CTL gene targets, including Eomes, effector molecules, and IL2Ra. Thus, our collective findings identify Aiolos as a pivotal regulator of CD4-CTL and TFH programming and highlight its potential as a target for manipulating CD4+ T cell responses.
Assuntos
Linfócitos T Auxiliares-Indutores , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Linfócitos T CD8-Positivos , Linfócitos T CD4-Positivos , Diferenciação CelularRESUMO
Loss of cytotoxicity and defective metabolism are linked to glycogen synthase kinase 3 beta (GSK3ß) overexpression in natural killer (NK) cells from patients with acute myeloid leukemia or from healthy donors after expansion ex vivo with IL-15. Drug inhibition of GSK3ß in these NK cells improves their maturation and cytotoxic activity, but the mechanisms of GSK3ß-mediated dysfunction have not been well studied. Here, we show that expansion of NK cells with feeder cells expressing membrane-bound IL-21 maintained normal GSK3ß levels, allowing us to study GSK3ß function using CRISPR gene editing. We deleted GSK3B and expanded paired-donor knockout and wild-type (WT) NK cells and then assessed transcriptional and functional alterations induced by loss of GSK3ß. Surprisingly, our data showed that deletion of GSK3B did not alter cytotoxicity, cytokine production, or maturation (as determined by CD57 expression). However, GSK3B-KO cells demonstrated significant changes in expression of genes related to rRNA processing, cell proliferation, and metabolic function, suggesting possible metabolic reprogramming. Next, we found that key genes downregulated in GSK3B-KO NK cells were upregulated in GSK3ß-overexpressing NK cells from AML patients, confirming this correlation in a clinical setting. Lastly, we measured cellular energetics and observed that GSK3B-KO NK cells exhibited 150% higher spare respiratory capacity, a marker of metabolic fitness. These findings suggest a role for GSK3ß in regulating NK cell metabolism.
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Cerebral malaria (CM), the deadliest complication of Plasmodium infection, is a complex and unpredictable disease. However, our understanding of the host and parasite factors that cause CM is limited. Using a mouse model of CM, experimental CM (ECM), we performed a three-way comparison between ECM-susceptible C57BL/6 mice infected with ECM-causing Plasmodium ANKA parasites [ANKA(C57BL/6)], ECM-resistant BALB/c mice infected with Plasmodium ANKA [ANKA(BALB/c)], and C57BL/6 mice infected with Plasmodium NK65 that does not cause ECM [NK65(C57BL/6)]. All ANKA(C57BL/6) mice developed CM. In contrast, in ANKA(BALB/c) and NK65(C57BL/6), infections do not result in CM and proceed similarly in terms of parasite growth, disease course, and host immune response. However, parasite gene expression in ANKA(BALB/c) was remarkably different than that in ANKA(C57BL/6) but similar to the gene expression in NK65(C57BL/6). Thus, Plasmodium ANKA has an ECM-specific gene expression profile that is activated only in susceptible hosts, providing evidence that the host has a critical influence on the outcome of infection. IMPORTANCE Hundreds of thousands of lives are lost each year due to the brain damage caused by malaria disease. The overwhelming majority of these deaths occur in young children living in sub-Saharan Africa. Thus far, there are no vaccines against this deadly disease, and we still do not know why fatal brain damage occurs in some children while others have milder, self-limiting disease progression. Our research provides an important clue to this problem. Here, we showed that the genetic background of the host has an important role in determining the course and the outcome of the disease. Our research also identified parasite molecules that can potentially be targeted in vaccination and therapy approaches.
Assuntos
Malária Cerebral , Animais , Camundongos , Malária Cerebral/parasitologia , Plasmodium berghei/fisiologia , Camundongos Endogâmicos C57BL , Expressão Gênica , Modelos Animais de DoençasRESUMO
Innate lymphocytes encompass a diverse array of phenotypic identities with specialized functions. DNA methylation and hydroxymethylation are essential for epigenetic fidelity and fate commitment. The landscapes of these modifications are unknown in innate lymphocytes. Here, we characterized the whole-genome distribution of methyl-CpG and 5-hydroxymethylcytosine (5hmC) in mouse innate lymphoid cell 3 (ILC3), ILC2 and natural killer (NK) cells. We identified differentially methylated regions (DMRs) and differentially hydroxymethylated regions (DHMRs) between ILC and NK cell subsets and correlated them with transcriptional signatures. We associated lineage-determining transcription factors (LDTFs) with demethylation and demonstrated unique patterns of DNA methylation/hydroxymethylation in relationship to open chromatin regions (OCRs), histone modifications and TF-binding sites. We further identified an association between hydroxymethylation and NK cell superenhancers (SEs). Using mice lacking the DNA hydroxymethylase TET2, we showed the requirement for TET2 in optimal production of hallmark cytokines by ILC3s and interleukin-17A (IL-17A) by inflammatory ILC2s. These findings provide a powerful resource for studying innate lymphocyte epigenetic regulation and decode the regulatory logic governing their identity.
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Metilação de DNA , Imunidade Inata , Animais , Cromatina/genética , Epigênese Genética , Imunidade Inata/genética , Células Matadoras Naturais , Linfócitos , CamundongosRESUMO
Cell identity and function largely rely on the programming of transcriptomes during development and differentiation. Signature gene expression programs are orchestrated by regulatory circuits consisting of cis-acting promoters and enhancers, which respond to a plethora of cues via the action of transcription factors. In turn, transcription factors direct epigenetic modifications to revise chromatin landscapes, and drive contacts between distal promoter-enhancer combinations. In immune cells, regulatory circuits for effector genes are especially complex and flexible, utilizing distinct sets of transcription factors and enhancers, depending on the cues each cell type receives during an infection, after sensing cellular damage, or upon encountering a tumor. Here, we review major players in the coordination of gene regulatory programs within innate and adaptive immune cells, as well as integrative omics approaches that can be leveraged to decipher their underlying circuitry.
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Cromatina , Redes Reguladoras de Genes , Animais , Regulação da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Fatores de Transcrição/genéticaRESUMO
Aberrant expression of nuclear transporters and deregulated subcellular localization of their cargo proteins are emerging as drivers and therapeutic targets of cancer. Here, we present evidence that the nuclear exporter exportin-6 and its cargo profilin-1 constitute a functionally important and frequently deregulated axis in cancer. Exportin-6 upregulation occurs in numerous cancer types and is associated with poor patient survival. Reducing exportin-6 level in breast cancer cells triggers antitumor effects by accumulating nuclear profilin-1. Mechanistically, nuclear profilin-1 interacts with eleven-nineteen-leukemia protein (ENL) within the super elongation complex (SEC) and inhibits the ability of the SEC to drive transcription of numerous pro-cancer genes including MYC. XPO6 and MYC are positively correlated across diverse cancer types including breast cancer. Therapeutically, exportin-6 loss sensitizes breast cancer cells to the bromodomain and extra-terminal (BET) inhibitor JQ1. Thus, exportin-6 upregulation is a previously unrecognized cancer driver event by spatially inhibiting nuclear profilin-1 as a tumor suppressor.
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Carioferinas/metabolismo , Neoplasias/metabolismo , Profilinas/antagonistas & inibidores , Profilinas/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Carioferinas/genética , Células MCF-7 , Camundongos , Camundongos Nus , Neoplasias/genética , Profilinas/genética , Análise de Sobrevida , Regulação para CimaRESUMO
Efficient repair of DNA double-strand breaks (DSBs) requires a coordinated DNA Damage Response (DDR), which includes phosphorylation of histone H2Ax, forming γH2Ax. This histone modification spreads beyond the DSB into neighboring chromatin, generating a DDR platform that protects against end disassociation and degradation, minimizing chromosomal rearrangements. However, mechanisms that determine the breadth and intensity of γH2Ax domains remain unclear. Here, we show that chromosomal contacts of a DSB site are the primary determinants for γH2Ax landscapes. DSBs that disrupt a topological border permit extension of γH2Ax domains into both adjacent compartments. In contrast, DSBs near a border produce highly asymmetric DDR platforms, with γH2Ax nearly absent from one broken end. Collectively, our findings lend insights into a basic DNA repair mechanism and how the precise location of a DSB may influence genome integrity.
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Quebras de DNA de Cadeia Dupla , Dano ao DNA , Reparo do DNA , Histonas/metabolismo , Animais , Linhagem Celular Transformada , Cromatina/metabolismo , Camundongos , FosforilaçãoRESUMO
Although the pathogen recognition receptor pathways that activate cell-intrinsic antiviral responses are well delineated, less is known about how the host regulates this response to prevent sustained signaling and possible immune-mediated damage. Using a genome-wide CRISPR-Cas9 screening approach to identify host factors that modulate interferon-stimulated gene (ISG) expression, we identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1), a previously described inhibitor of retrovirus integration, as a modulator of basal cell-intrinsic immunity. Ablation of Banf1 by gene editing resulted in chromatin activation near host defense genes with associated increased expression of ISGs, including Oas2, Rsad2 (viperin), Ifit1, and ISG15 The phenotype in Banf1-deficient cells occurred through a cGAS-, STING-, and IRF3-dependent signaling axis, was associated with reduced infection of RNA and DNA viruses, and was reversed in Banf1 complemented cells. Confocal microscopy and biochemical studies revealed that a loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline. Our study identifies an undescribed role for Banf1 in regulating the levels of cytoplasmic DNA and cGAS-dependent ISG homeostasis and suggests possible therapeutic directions for promoting or inhibiting cell-intrinsic innate immune responses.IMPORTANCE Although the interferon (IFN) signaling pathway is a key host mechanism to restrict infection of a diverse range of viral pathogens, its unrestrained activity either at baseline or in the context of an immune response can result in host cell damage and injury. Here, we used a genome-wide CRISPR-Cas9 screen and identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1) as a modulator of basal cell-intrinsic immunity. A loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline, which triggered IFN-stimulated gene expression via a cGAS-STING-IRF3 axis that did not require type I IFN or STAT1 signaling. Our experiments define a regulatory network in which Banf1 limits basal inflammation by preventing self DNA accumulation in the cytosol.
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Proteínas de Ligação a DNA/imunologia , Interações Hospedeiro-Patógeno , Proteínas de Membrana/imunologia , Proteínas Nucleares/imunologia , Nucleotidiltransferases/imunologia , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Proteínas de Ligação a DNA/genética , Edição de Genes , Regulação da Expressão Gênica , Homeostase/imunologia , Humanos , Imunidade Inata , Interferons/imunologia , Camundongos , Microglia/imunologia , Proteínas Nucleares/genética , Transdução de SinaisRESUMO
Atopic dermatitis (AD) is a widespread, chronic skin disease associated with aberrant allergic inflammation. Current treatments involve either broad or targeted immunosuppression strategies. However, enhancing the immune system to control disease remains untested. We demonstrate that patients with AD harbor a blood natural killer (NK) cell deficiency that both has diagnostic value and improves with therapy. Multidimensional protein and RNA profiling revealed subset-level changes associated with enhanced NK cell death. Murine NK cell deficiency was associated with enhanced type 2 inflammation in the skin, suggesting that NK cells play a critical immunoregulatory role in this context. On the basis of these findings, we used an NK cell-boosting interleukin-15 (IL-15) superagonist and observed marked improvement in AD-like disease in mice. These findings reveal a previously unrecognized application of IL-15 superagonism, currently in development for cancer immunotherapy, as an immunotherapeutic strategy for AD.
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Dermatite Atópica , Deficiência de GATA2 , Animais , Dermatite Atópica/terapia , Modelos Animais de Doenças , Humanos , Imunoterapia , Células Matadoras Naturais , CamundongosRESUMO
DNA damage responses (DDR) to double-strand breaks (DSBs) alter cellular transcription programs at the genome-wide level. Through processes that are less well understood, DSBs also alter transcriptional responses locally, which may be important for efficient DSB repair. Here, we developed an approach to elucidate the cis-acting responses to DSBs in G1 phase cells. We found that DSBs within a gene body silence its expression, as well as the transcription of local undamaged genes at a distance defined by the spread of γ-H2AX from the DSB. Importantly, DSBs not only repress ongoing transcription but also block the inducible expression of regional genes. DSB-mediated transcriptional repression depends on DDR signaling but does not require the generation of inaccessible chromatin. Our findings demonstrate that in G1 phase cells, DDR signaling establishes a robust and extensive region of transcriptional repression spreading from DSB sites and introduce an approach to study the mechanistic impact of targeted DNA breaks in nearly any chromatin environment.
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Reparo do DNA/genética , Fase G1/genética , Elementos Silenciadores Transcricionais/genética , Animais , Ciclo Celular/genética , Linhagem Celular , DNA/genética , Quebras de DNA de Cadeia Dupla , Dano ao DNA/fisiologia , Reparo do DNA por Junção de Extremidades/genética , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Fase G1/fisiologia , Humanos , Camundongos , Elementos Reguladores de Transcrição/genética , Elementos Reguladores de Transcrição/fisiologia , Elementos Silenciadores Transcricionais/fisiologiaRESUMO
Many gut functions are attuned to circadian rhythm. Intestinal group 3 innate lymphoid cells (ILC3s) include NKp46+ and NKp46- subsets, which are RORγt dependent and provide mucosal defense through secretion of interleukin-22 (IL-22) and IL-17. Because ILC3s highly express some key circadian clock genes, we investigated whether ILC3s are also attuned to circadian rhythm. We noted circadian oscillations in the expression of clock and cytokine genes, such as REV-ERBα, IL-22, and IL-17, whereas acute disruption of the circadian rhythm affected cytokine secretion by ILC3s. Because of prominent and rhythmic expression of REV-ERBα in ILC3s, we also investigated the impact of constitutive deletion of REV-ERBα, which has been previously shown to inhibit the expression of a RORγt repressor, NFIL3, while also directly antagonizing DNA binding of RORγt. Development of the NKp46+ ILC3 subset was markedly impaired, with reduced cell numbers, RORγt expression, and IL-22 production in REV-ERBα-deficient mice. The NKp46- ILC3 subsets developed normally, potentially due to compensatory expression of other clock genes, but IL-17 secretion paradoxically increased, probably because RORγt was not antagonized by REV-ERBα. We conclude that ILC3s are attuned to circadian rhythm, but clock regulator REV-ERBα also has circadian-independent impacts on ILC3 development and functions due to its roles in the regulation of RORγt.
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Ritmo Circadiano/imunologia , Imunidade Inata/imunologia , Intestinos/imunologia , Linfócitos/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Animais , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/deficiência , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/imunologiaRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Innate lymphoid cells (ILCs) are tissue-resident lymphocytes categorized on the basis of their core regulatory programs and the expression of signature cytokines. Human ILC3s that produce the cytokine interleukin-22 convert into ILC1-like cells that produce interferon-γ in vitro, but whether this conversion occurs in vivo remains unclear. In the present study we found that ILC3s and ILC1s in human tonsils represented the ends of a spectrum that included additional discrete subsets. RNA velocity analysis identified an intermediate ILC3-ILC1 cluster, which had strong directionality toward ILC1s. In humanized mice, the acquisition of ILC1 features by ILC3s showed tissue dependency. Chromatin studies indicated that the transcription factors Aiolos and T-bet cooperated to repress regulatory elements active in ILC3s. A transitional ILC3-ILC1 population was also detected in the human intestine. We conclude that ILC3s undergo conversion into ILC1-like cells in human tissues in vivo, and that tissue factors and Aiolos were required for this process.