RESUMO
The generation of lymphoid tissues during embryogenesis relies on group 3 innate lymphoid cells (ILC3) displaying lymphoid tissue inducer (LTi) activity and expressing the master transcription factor RORγt. Accordingly, RORγt-deficient mice lack ILC3 and lymphoid structures, including lymph nodes (LN). Whereas T-bet affects differentiation and functions of ILC3 postnatally, the role of T-bet in regulating fetal ILC3 and LN formation remains completely unknown. Using multiple mouse models and single-cell analyses of fetal ILCs and ILC progenitors (ILCP), here we identify a key role for T-bet during embryogenesis and show that its deficiency rescues LN formation in RORγt-deficient mice. Mechanistically, T-bet deletion skews the differentiation fate of fetal ILCs and promotes the accumulation of PLZFhi ILCP expressing central LTi molecules in a RORα-dependent fashion. Our data unveil an unexpected role for T-bet and RORα during embryonic ILC function and highlight that RORγt is crucial in counteracting the suppressive effects of T-bet.
Assuntos
Diferenciação Celular/imunologia , Imunidade Inata/imunologia , Linfonodos/imunologia , Linfócitos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Proteínas com Domínio T/imunologia , Animais , Linhagem da Célula/imunologia , Feminino , Tecido Linfoide/imunologia , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Auxiliares-Indutores/imunologiaRESUMO
The transcription factor Rora has been shown to be important for the development of ILC2 and the regulation of ILC3, macrophages and Treg cells. Here we investigate the role of Rora across CD4+ T cells in general, but with an emphasis on Th2 cells, both in vitro as well as in the context of several in vivo type 2 infection models. We dissect the function of Rora using overexpression and a CD4-conditional Rora-knockout mouse, as well as a RORA-reporter mouse. We establish the importance of Rora in CD4+ T cells for controlling lung inflammation induced by Nippostrongylus brasiliensis infection, and have measured the effect on downstream genes using RNA-seq. Using a systematic stimulation screen of CD4+ T cells, coupled with RNA-seq, we identify upstream regulators of Rora, most importantly IL-33 and CCL7. Our data suggest that Rora is a negative regulator of the immune system, possibly through several downstream pathways, and is under control of the local microenvironment.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Macrófagos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Pneumonia/imunologia , Células Th2/imunologia , Animais , Antígenos de Helmintos/imunologia , Antígenos de Helmintos/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Nippostrongylus/imunologia , Pneumonia/parasitologia , Pneumonia/patologia , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologiaRESUMO
Lung group 2 innate lymphoid cells (ILC2s) drive allergic inflammation and promote tissue repair. ILC2 development is dependent on the transcription factor retinoic acid receptor-related orphan receptor (RORα), which is also expressed in common ILC progenitors. To elucidate the developmental pathways of lung ILC2s, we generated RORα lineage tracer mice and performed single-cell RNA sequencing, flow cytometry, and functional analyses. In adult mouse lungs, we found an IL-18Rα+ST2- population different from conventional IL-18Rα-ST2+ ILC2s. The former was GATA-3intTcf7EGFP+Kit+, produced few cytokines, and differentiated into multiple ILC lineages in vivo and in vitro. In neonatal mouse lungs, three ILC populations were identified, namely an ILC progenitor population similar to that in adult lungs and two distinct effector ILC2 subsets that differentially produced type 2 cytokines and amphiregulin. Lung ILC progenitors might actively contribute to ILC-poiesis in neonatal and inflamed adult lungs. In addition, neonatal lung ILC2s include distinct proinflammatory and tissue-repairing subsets.
Assuntos
Imunidade Inata/imunologia , Pulmão/imunologia , Linfócitos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Células-Tronco/imunologia , Anfirregulina/imunologia , Animais , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Citocinas/imunologia , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Célula Única/métodosRESUMO
We investigated the role of epiphyseal hormone melatonin in the differentiation of naive CD4+ T cells into regulatory T cells (Treg). The hormone at physiological and pharmacological concentrations inhibited Treg differentiation, decreasing both the proportion of CD4+FOXP3+ cells in the culture and the level of TGF-ß, the key cytokine for this T cell subpopulation. The inhibitory effect of exogenous melatonin was due to its interaction with the membrane receptors MT1 and MT2. At the same time, the signals realized through RORα-the nuclear receptor for melatonin-stimulated Treg formation; however, they were considerably weaker than the signals from the membrane receptors and were overlapped by the latter. Since the Treg subpopulation plays an important role in physiological and pathological processes in the body, the revealed effects of melatonin should be taken into account in its therapeutic use.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Melatonina/farmacologia , Linfócitos T Reguladores/imunologia , Adulto , Diferenciação Celular/imunologia , Feminino , Humanos , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Receptor MT1 de Melatonina/imunologia , Receptor MT2 de Melatonina/imunologia , Linfócitos T Reguladores/citologia , Fator de Crescimento Transformador beta/imunologiaRESUMO
ROR family of nuclear receptor transcription factors forms nodes connecting metabolic and inflammatory signaling pathways. The RORα members of the family have intrinsic transcriptional activity and they are involved in both activation and repression of a wide range of genes. The role of RORα in control of inflammation has been extensively studied using animal models but its function in human cells is not as well understood. To address this shortcoming, we analyzed how RORα is shaping the inflammatory state of human macrophages. Using CRISPR-Cas9 system, we deleted RORA in THP-1 human monocytic cell line. In mutant cells we observed a dramatic increase in basal expression of a subset of NF-κB regulated genes, including TNF, IL-1ß and IL-6, at both transcriptional and translational levels. Furthermore, RORA-deletion cells produced notable amounts of pro-IL-1ß even in the absence of LPS stimulation. Subsequent LPS stimulation induced cleavage of pro-IL-1ß to mature form. Our RNAseq analysis further confirmed the key role of RORA in setting the inflammatory state of macrophages and defined the set of differentially regulated genes. Overall, our data provides evidence supporting the anti-inflammatory function of RORα in human macrophages.
Assuntos
Citocinas/imunologia , Regulação da Expressão Gênica/imunologia , Macrófagos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Biossíntese de Proteínas/imunologia , Transcrição Gênica/imunologia , Citocinas/genética , Deleção de Genes , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Macrófagos/patologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Biossíntese de Proteínas/efeitos dos fármacos , Células THP-1 , Transcrição Gênica/efeitos dos fármacosRESUMO
Atopic dermatitis is an allergic inflammatory skin disease characterized by the production of the type 2 cytokines in the skin by type 2 innate lymphoid cells (ILC2s) and T helper 2 (TH2) cells, and tissue eosinophilia. Using two distinct mouse models of atopic dermatitis, we show that expression of retinoid-related orphan receptor α (RORα) in skin-resident T regulatory cells (Tregs) is important for restraining allergic skin inflammation. In both models, targeted deletion of RORα in mouse Tregs led to exaggerated eosinophilia driven by interleukin-5 (IL-5) production by ILC2s and TH2 cells. Expression of RORα in skin-resident Tregs suppressed IL-4 expression and enhanced expression of death receptor 3 (DR3), which is the receptor for tumor necrosis factor (TNF) family cytokine, TNF ligand-related molecule 1 (TL1A), which promotes Treg functions. DR3 is expressed on both ILC2s and skin-resident Tregs Upon deletion of RORα in skin-resident Tregs, we found that Tregs were no longer able to sequester TL1A, resulting in enhanced ILC2 activation. We also documented higher expression of RORα in skin-resident Tregs than in peripheral blood circulating Tregs in humans, suggesting that RORα and the TL1A-DR3 circuit could be therapeutically targeted in atopic dermatitis.
Assuntos
Dermatite Atópica/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Reguladores/imunologia , Animais , Feminino , Humanos , Imunidade Inata , Camundongos Transgênicos , Membro 25 de Receptores de Fatores de Necrose Tumoral/imunologia , Pele/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologiaRESUMO
Macrophages are able to polarize to pro-inflammatory M1 or anti-inflammatory M2 states with distinct phenotypes and physiological functions. RORα is a member of the nuclear receptor super family and plays important roles in lipid, glucose metabolism, as well as the inflammatory response. In this study, we examined the potential function of RORα in the regulation of macrophage polarization. Treatment of RAW264.7 macrophages with RORα agonist cholesterol sulfate (CH-S) and overexpression of RORα increased M2 macrophage markers expressions (Arg1, Ym1 and Fizz1) both on mRNA and protein levels. Conversely, selective antagonism (SR1001) abrogated the induction of M2 macrophage markers which induced by CH-S. In addition, CH-S induced phosphorylation of Adenosine monophosphate (AMP)-activated protein kinase α (AMPKα), which was accompanied by the activation of acetyl-CoA carboxylase 1 (ACC). However, SR1001 abolished the activation of AMPKα and ACC induced by CH-S. Meanwhile, inactivation of AMPKα by its inhibitor Compound C (CompC) abrogated the mRNA and protein levels of CH-S-induced M2 macrophage markers expressions. Together these findings reveal that RORα regulates macrophage M2 polarization via activation of AMPKα, which may provide a novel beneficial effect of RORα against inflammation.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Diferenciação Celular/imunologia , Macrófagos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Proteínas Quinases Ativadas por AMP/imunologia , Animais , Western Blotting , Ativação Enzimática/imunologia , Citometria de Fluxo , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células RAW 264.7RESUMO
Detrimental Th17 driven inflammatory and autoimmune disease such as Crohn's disease, graft versus host disease and multiple sclerosis remain a significant cause of morbidity and mortality worldwide. Multipotent stromal/stem cell (MSC) inhibit Th17 polarization and activation in vitro and in rodent models. As such, MSC based therapeutic approaches are being investigated as novel therapeutic approaches to treat Th17 driven diseases in humans. The significance of naturally occurring diseases in dogs is increasingly recognized as a realistic platform to conduct pre-clinical testing of novel therapeutics. Full characterization of Th17 cells in dogs has not been completed. We have developed and validated a flow-cytometric method to detect Th17 cells in canine blood. We further demonstrate that Th17 and other IL17 producing cells are present in tissues of dogs with naturally occurring chronic inflammatory diseases. Finally, we have determined the kinetics of a canine specific Th17 polarization in vitro and demonstrate that canine MSC inhibit Th17 polarization in vitro, in a PGE2 independent mechanism. Our findings provide fundamental research tools and suggest that naturally occurring diseases in dogs, such as inflammatory bowel disease, may be harnessed to translate novel MSC based therapeutic strategies that target the Th17 pathway.
Assuntos
Diferenciação Celular/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Doenças do Cão/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Dermatite/imunologia , Dermatite/patologia , Dermatite/terapia , Dermatite/veterinária , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Doenças do Cão/terapia , Cães , Regulação da Expressão Gênica , Gengivite/imunologia , Gengivite/patologia , Gengivite/terapia , Gengivite/veterinária , Humanos , Imunofenotipagem , Inflamação , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/veterinária , Interleucina-17/genética , Interleucina-17/imunologia , Meningoencefalite/imunologia , Meningoencefalite/patologia , Meningoencefalite/terapia , Meningoencefalite/veterinária , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Cultura Primária de Células , Receptores CCR6/genética , Receptores CCR6/imunologia , Receptores de Interleucina/genética , Receptores de Interleucina/imunologia , Linfócitos T Reguladores/citologia , Células Th17/citologia , Pesquisa Translacional Biomédica/métodosRESUMO
We determined the NF-κB- and NOD-like receptor (NLR)P3-dependent molecular mechanisms involved in sepsis and evaluated the role of retinoid-related orphan receptor (ROR)-α in melatonin's anti-inflammatory actions. Western blot, RT-PCR, ELISA, and spectrophotometric analysis revealed that NF-κB and NLRP3 closely interact, leading to proinflammatory and pro-oxidant status in heart tissue of septic C57BL/6J mice. Moreover, mitochondrial oxygen consumption was reduced by 80% in septic mice. In vivo and in vitro analysis showed that melatonin administration blunts NF-κB transcriptional activity through a sirtuin1-dependent NF-κB deacetylation in septic mice. Melatonin also decreased NF-κB-dependent proinflammatory response and restored redox balance and mitochondrial homeostasis, thus inhibiting the NLRP3 inflammasome. In an important finding, the inhibition of NF-κB by melatonin, but not that of NLRP3, was blunted in RORα (sg/sg) mice, indicating that functional RORα transcription factor is necessary for the initiation of the innate immune response against inflammation. Our results are evidence of the NF-κB/NLRP3 connection during sepsis and identify NLRP3 as a novel molecular target for melatonin. The multiple molecular targets of melatonin in this study explain its potent anti-inflammatory efficacy against systemic innate immune activation and herald a promising therapeutic application for melatonin in the treatment of sepsis.
Assuntos
Proteínas de Transporte/metabolismo , Imunidade Inata/efeitos dos fármacos , Melatonina/farmacologia , NF-kappa B/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Sepse/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Imunidade Inata/genética , Camundongos , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Oxirredução/efeitos dos fármacos , Sepse/genética , Sepse/imunologia , Sepse/patologiaRESUMO
Genetic studies have added to the understanding of complex diseases. Here, we used a combined genetic approach for risk-loci identification in a prototypic, organ-specific, autoimmune disease, namely experimental epidermolysis bullosa acquisita (EBA), in which autoantibodies to type VII collagen (COL7) and neutrophil activation cause mucocutaneous blisters. Anti-COL7 IgG induced moderate blistering in most inbred mouse strains, while some showed severe disease or were completely protected. Using publicly available genotyping data, we identified haplotype blocks that control blistering and confirmed two haplotype blocks in outbred mice. To identify the blistering-associated genes, haplotype blocks encoding genes that are differentially expressed in EBA-affected skin were considered. This procedure identified nine genes, including retinoid-related orphan receptor alpha (RORα), known to be involved in neurological development and function. After anti-COL7 IgG injection, RORα+/- mice showed reduced blistering and homozygous mice were completely resistant to EBA induction. Furthermore, pharmacological RORα inhibition dose-dependently blocked reactive oxygen species (ROS) release from activated neutrophils but did not affect migration or phagocytosis. Thus, forward genomics combined with multiple validation steps identifies RORα to be essential to drive inflammation in experimental EBA.
Assuntos
Epidermólise Bolhosa Adquirida/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Pele/metabolismo , Animais , Autoanticorpos/imunologia , Colágeno Tipo VII/imunologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Agonismo Parcial de Drogas , Epidermólise Bolhosa Adquirida/genética , Epidermólise Bolhosa Adquirida/imunologia , Epidermólise Bolhosa Adquirida/patologia , Predisposição Genética para Doença , Genômica/métodos , Haplótipos , Heterozigoto , Homozigoto , Imunoglobulina G/imunologia , Camundongos Knockout , Ativação de Neutrófilo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/deficiência , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Especificidade da Espécie , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Fatores de TempoRESUMO
Newly identified nuocytes or group 2 innate lymphoid cells (ILC2s) play an important role in Th2 cell mediated immunity such as protective immune responses to helminth parasites, allergic asthma, and chronic rhinosinusitis. However, the contributions of ILC2s in the occurrence and development of cancer remain unknown. Our previous study found that there was a predominant Th2 phenotype in patients with gastric cancer. In this study, the ILC2s related genes or molecules in PBMC from patients with gastric cancer were measured, and the potential correlation between them was analyzed. The expression levels of RORα, GATA3, T1/ST2, IL-17RB, CRTH2, IL-33, IL-5, and IL-4 mRNA were significantly increased in patients, but no significant changes were found in ICOS, CD45, and IL-13 expression, and there was a positive correlation between RORα or IL-13 and other related factors, such as ICOS and CD45. The increased frequency of ILC2s was also found in PBMC of patients by flow cytometry. In addition, the mRNA of Arg1 and iNOS were also significantly increased in patients. These results suggested that there are polarized ILC2s in gastric cancer patients which might contribute to immunosuppressive microenvironment and closely related to the upregulation of MDSCs and M2 macrophages.
Assuntos
Expressão Gênica/imunologia , Linfócitos/imunologia , Neoplasias Gástricas/imunologia , Microambiente Tumoral/imunologia , Adulto , Idoso , Citocinas/genética , Citocinas/imunologia , Feminino , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/imunologia , Humanos , Imunidade Inata , Imunofenotipagem , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Linfócitos/patologia , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Células Th2/imunologia , Células Th2/patologiaRESUMO
Acne vulgaris is the most common skin disorder affecting millions of people worldwide and inflammation resulting from the immune response targeting Propionibacterium acnes has a significant role in its pathogenesis. In this study, we have demonstrated that P. acnes is a potent inducer of T helper 17 (Th17) and Th1, but not Th2 responses in human peripheral blood mononuclear cells (PBMCs). P. acnes stimulated expression of key Th17-related genes, including IL-17A, RORα, RORc, IL-17RA, and IL-17RC, and triggered IL-17 secretion from CD4(+), but not from CD8(+) T cells. Supernatants from P. acnes-stimulated PBMCs were sufficient to promote the differentiation of naive CD4(+)CD45RA T cells into Th17 cells. Furthermore, we found that the combination of IL-1ß, IL-6, and transforming growth factor-ß-neutralizing antibodies completely inhibited P. acnes-induced IL-17 production. Importantly, we showed that IL-17-expressing cells were present in skin biopsies from acne patients but not from normal donors. Finally, vitamin A (all-trans retinoic acid) and vitamin D (1,25-dihydroxyvitamin D3) inhibited P. acnes-induced Th17 differentiation. Together, our data demonstrate that IL-17 is induced by P. acnes and expressed in acne lesions and that both vitamin A and D could be effective tools to modulate Th17-mediated diseases such as acne.
Assuntos
Acne Vulgar/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Interleucina-17/imunologia , Propionibacterium acnes/imunologia , Vitamina A/metabolismo , Vitamina D/imunologia , Acne Vulgar/microbiologia , Acne Vulgar/patologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Diferenciação Celular/imunologia , Infecções por Bactérias Gram-Positivas/patologia , Humanos , Interleucina-17/metabolismo , Interleucinas/imunologia , Interleucinas/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Receptores de Interleucina/imunologia , Receptores de Interleucina/metabolismo , Receptores de Interleucina-17/imunologia , Receptores de Interleucina-17/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th1/microbiologia , Células Th17/citologia , Células Th17/imunologia , Células Th17/microbiologia , Interleucina 22Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Regulação da Expressão Gênica/imunologia , Centro Germinativo/imunologia , MicroRNAs/imunologia , Proteínas Nucleares/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Fosfoproteínas Fosfatases/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , AnimaisRESUMO
Follicular helper T cells (TFH cells) are the prototypic helper T cell subset specialized to enable B cells to form germinal centers (GCs) and produce high-affinity antibodies. We found that expression of microRNAs (miRNAs) by T cells was essential for TFH cell differentiation. More specifically, we show that after immunization of mice with protein, the miRNA cluster miR-17â¼92 was critical for robust differentiation and function of TFH cells in a cell-intrinsic manner that occurred regardless of changes in proliferation. In a viral infection model, miR-17â¼92 restrained the expression of genes 'inappropriate' to the TFH cell subset, including the direct miR-17â¼92 target Rora. Removal of one Rora allele partially 'rescued' the inappropriate gene signature in miR-17â¼92-deficient TFH cells. Our results identify the miR-17â¼92 cluster as a critical regulator of T cell-dependent antibody responses, TFH cell differentiation and the fidelity of the TFH cell gene-expression program.
Assuntos
Diferenciação Celular/imunologia , Regulação da Expressão Gênica/imunologia , MicroRNAs/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Imunidade Adaptativa/imunologia , Animais , Infecções por Arenaviridae/imunologia , Infecções por Arenaviridae/virologia , Citometria de Fluxo , Imuno-Histoquímica , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Estatísticas não Paramétricas , Linfócitos T Auxiliares-Indutores/citologiaRESUMO
Infections with highly pathogenic avian influenza viruses (HPAIV) in humans lead to systemic disease associated with cytokine storm and multiorgan failure. In this study we aimed to identify the role of monocytes for the host response to HPAIV infection. Using genome-wide microarray analysis, we surprisingly demonstrate a reduced immune response of human monocytes to HPAIV H5N1 compared to human influenza A viruses. In bioinformatic analyses we could reveal a potential role of the Rar-related orphan receptor alpha (RORα) for the gene expression pattern induced by H5N1. RORα is known as an inhibitor of NF-κB signaling. We provide evidence that in monocytes RORα is activated by H5N1, resulting in inhibited NF-κB signaling. Using murine Hoxb8-immortalized RORαâ»/â», monocytes rescued NF-κB signaling upon H5N1 infection, confirming the biological relevance of RORα as an H5N1-induced mediator of monocytic immunosuppression. In summary, our study reveals a novel RORα-dependent escape mechanism by which H5N1 prevents an effective inflammatory response of monocytes blocking NF-κB-dependent gene expression.
Assuntos
Virus da Influenza A Subtipo H5N1/imunologia , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Monócitos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Antígenos Virais/imunologia , Linhagem Celular Transformada , Biologia Computacional , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imunidade/genética , Influenza Humana/genética , Camundongos , Análise em Microsséries , Monócitos/virologia , NF-kappa B/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Transdução de Sinais/genéticaRESUMO
Two years ago, T helper cells, including Th1, Th2 and Th17 cells, were considered to be the most significant sources of cytokine during the orchestration of immune responses in the lung. Following the discovery of innate lymphoid cells, we now know that these previously unappreciated cytokine-secreting cells, including ILC1 (IFN-γ-expressing NK cells), ILC2 (IL-5 and IL-13-expressing nuocytes) and RORγ ILC (IL-17 and IL-22-expressing 'ILC3') are important mediators in immune processes. Herein we review the role of ILC2 specifically in inflammatory lung responses with special attention to allergen-induced and viral-induced type 2 lung disease.
Assuntos
Asma/imunologia , Hipersensibilidade/imunologia , Linfócitos/fisiologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Humanos , Interleucina-13/metabolismo , Interleucina-5/metabolismo , Células Th1/fisiologia , Células Th17/fisiologia , Células Th2/fisiologiaRESUMO
Natural helper (NH) cells are innate lymphoid cells (ILCs) that produce T helper-2 (Th2)-cell-type cytokines in the lung- and gut-associated lymphoid tissues. Currently, the lineage relationship between NH cells in different tissues and between NH cells and interleukin-22 (IL-22)-producing retinoic-acid-receptor-related orphan receptor (ROR)γt-positive ILCs is unclear. Here, we report that NH cells express RORα, but not RORγt. RORα-deficient, but not RORγt-deficient, mice lacked NH cells in all tissues, whereas all other lymphocytes, including RORγt(+) ILCs, were unaffected. NH-cell-deficient mice generated by RORα-deficient bone-marrow transplantation had normal Th2 cell responses but failed to develop acute lung inflammation in response to protease allergen, thus confirming the essential role of NH cells in allergic lung inflammation. We have also identified RORα-dependent NH cell progenitors in the bone marrow. Thus, all NH cells belong to a unique RORα-dependent cell lineage separate from other lymphoid cell lineages.
Assuntos
Células da Medula Óssea/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Pneumonia/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Alérgenos/imunologia , Animais , Antígenos Ly/genética , Antígenos Ly/imunologia , Células da Medula Óssea/metabolismo , Transplante de Medula Óssea , Linhagem da Célula/imunologia , Células Cultivadas , Feminino , Citometria de Fluxo , Subunidade gama Comum de Receptores de Interleucina/genética , Subunidade gama Comum de Receptores de Interleucina/imunologia , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Papaína/imunologia , Pneumonia/genética , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Células Th2/imunologia , Células Th2/metabolismoRESUMO
Nuocytes are essential in innate type 2 immunity and contribute to the exacerbation of asthma responses. Here we found that nuocytes arose in the bone marrow and differentiated from common lymphoid progenitors, which indicates they are distinct, previously unknown members of the lymphoid lineage. Nuocytes required interleukin 7 (IL-7), IL-33 and Notch signaling for development in vitro. Pro-T cell progenitors at double-negative stage 1 (DN1) and DN2 maintained nuocyte potential in vitro, although the thymus was not essential for nuocyte development. Notably, the transcription factor RORα was critical for the development of nuocytes and their role in the expulsion of parasitic worms.
Assuntos
Diferenciação Celular , Leucócitos/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Animais , Interleucina-7/imunologia , Interleucina-7/metabolismo , Leucócitos/citologia , Leucócitos/metabolismo , Camundongos , Nippostrongylus/imunologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Transdução de Sinais , Infecções por Strongylida/imunologia , Timócitos/imunologiaRESUMO
The Th17 cells use the retinoid-related orphan receptor-γ (Rorg or Rorc) to specify their differentiation and lineage-specific function. However, how Rorg is switched on during Th17 differentiation is unknown. We report here that c-Rel and RelA/p65 transcription factors drive Th17 differentiation by binding to and activating two distinct Rorg promoters that control RORγT and RORγ expression, respectively. Similar to RORγT, RORγ is selectively expressed in Th17 cells and is effective in specifying the Th17 phenotype. T cells deficient in c-Rel or RelA are significantly compromised in Th17 differentiation, and c-Rel-deficient mice are defective in Th17 responses. Thus, Th17 immunity is controlled by a Rel-RORγ-RORγT axis, and strategies targeting Rel/NF-κB can be effective for controlling Th17 cell-mediated diseases.
Assuntos
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Proteínas Proto-Oncogênicas c-rel/imunologia , Células Th17/imunologia , Transcrição Gênica , Animais , Diferenciação Celular/imunologia , Humanos , Interleucina-17/genética , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-rel/genética , Transdução de Sinais/imunologia , Células Th17/fisiologia , Fator de Transcrição RelA/imunologiaRESUMO
OBJECTIVE: To investigate the molecular mechanism for biased interleukin-17 (IL-17) production by DBA/1 CD4+ T cells upon T cell receptor (TCR) and transforming growth factor ß (TGFß) stimulation. METHODS: Purified naive CD4+ T cells were stimulated with anti-CD3/CD28 under Th1, Th2, Th17, and induced T regulatory (iTreg) cell conditions. Cytokine production was assayed by intracellular staining and enzyme-linked immunosorbent assay. Expression of transcription factors was determined by reverse transcription-polymerase chain reaction, flow cytometry, and immunoblotting techniques. RESULTS: Naive CD4+ T cells from DBA/1 mice produced more IL-17 under Th17 cell polarizing conditions as compared with those from C57BL/6 or BALB/c mice. Further investigation revealed no difference among the strains in terms of CD4+ T cell survival, upstream TCR signaling, or CD69 expression or in the phosphorylation of STAT-3 and expression of suppressor of cytokine signaling 3 that positively or negatively regulate IL-17 cell production. However, DBA/1 CD4+ T cells expressed increased levels of retinoic acid-related orphan receptor γt (RORγt). Furthermore, under iTreg cell polarizing conditions, DBA/1 CD4+ T cells showed a strikingly reduced level of FoxP3 expression. When interferon-γ and IL-4 were blocked, FoxP3 expression increased but remained lower in DBA/1 CD4+ T cells following exposure to TGFß as compared with C57BL/6 CD4+ T cells. Moreover, DBA/1 CD4+ T cells showed reduced phosphorylation of Smad2 and Smad3 under both Th17 and iTreg cell polarizing conditions. CONCLUSION: These results indicate that naive CD4+ T cells from DBA/1 mice have a dichotomous response to TGFß: enhanced RORγt, yet reduced FoxP3, up-regulation. This observation may help to elucidate the branch point of TGFß signaling that leads to skewed Th17, but reduced iTreg, cell differentiation.