RESUMO
Dendritic cells (DCs) control the balance between effector T cells and regulatory T cells in vivo. Hence, the study of DCs might identify mechanisms of disease pathogenesis and guide new therapeutic approaches for disorders mediated by the immune system. We found that interleukin 27 (IL-27) signaling in mouse DCs limited the generation of effector cells of the TH1 and TH17 subsets of helper T cells and the development of experimental autoimmune encephalomyelitis (EAE). The effects of IL-27 were mediated at least in part through induction of the immunoregulatory molecule CD39 in DCs. IL-27-induced CD39 decreased the extracellular concentration of ATP and downregulated nucleotide-dependent activation of the NLRP3 inflammasome. Finally, therapeutic vaccination with IL-27-conditioned DCs suppressed established relapsing-remitting EAE. Thus, IL-27 signaling in DCs limited pathogenic T cell responses and the development of autoimmunity.
Assuntos
Antígenos CD/genética , Apirase/genética , Autoimunidade , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Interleucina-17/farmacologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Animais , Anticorpos/imunologia , Apresentação de Antígeno/efeitos dos fármacos , Apresentação de Antígeno/imunologia , Antígenos CD/metabolismo , Apirase/metabolismo , Autoanticorpos/imunologia , Autoimunidade/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Citocinas/biossíntese , Células Dendríticas/metabolismo , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Camundongos , Camundongos Knockout , Bainha de Mielina/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Receptores de Citocinas/genética , Receptores de Citocinas/metabolismo , Receptores de Interleucina , Transdução de Sinais , Subpopulações de Linfócitos T/citologia , Transcrição Gênica/efeitos dos fármacosRESUMO
CD4(+) interleukin 17 (IL-17)-producing helper T cells (T(H)17 cells) are instrumental in the immune response to pathogens. However, an overactive T(H)17 response results in tissue inflammation and autoimmunity, and therefore it is important to identify the molecular mechanisms that control the development of T(H)17 cells. IL-2 suppresses such development, but how IL-2 production is actively suppressed during T(H)7 differentiation is not understood. Here we report that under T(H)17-polarizing conditions, the transcription factors STAT3 and AhR upregulated the expression of Aiolos, a member of the Ikaros family of transcription factors. Using Aiolos-deficient mice, we demonstrated that Aiolos silenced the Il2 locus, promoting T(H)17 differentiation in vitro and in vivo. Thus, we have identified a module in the transcriptional program of T(H)17 cells that actively limits IL-2 production and promotes their differentiation.
Assuntos
Interleucina-2/biossíntese , Ativação Linfocitária , Células Th17/metabolismo , Transativadores/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Células Cultivadas , Colite/imunologia , Regulação da Expressão Gênica , Fator de Transcrição Ikaros , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Th17/citologia , Células Th17/imunologia , Transativadores/deficiência , Transativadores/genéticaRESUMO
Diagnosing primary central nervous system lymphoma (PCNSL) frequently requires neurosurgical biopsy due to nonspecific radiologic features and the low yield of cerebrospinal fluid (CSF) studies. We characterized the clinical evaluation of suspected PCNSL (N = 1007 patients) and designed a rapid multiplexed genotyping assay for MYD88, TERT promoter, IDH1/2, H3F3A, and BRAF mutations to facilitate the diagnosis of PCNSL from CSF and detect other neoplasms in the differential diagnosis. Among 159 patients with confirmed PCNSL, the median time to secure a diagnosis of PCNSL was 10 days, with a range of 0 to 617 days. Permanent histopathology confirmed PCNSL in 142 of 152 biopsies (93.4%), whereas CSF analyses were diagnostic in only 15/113 samplings (13.3%). Among 86 archived clinical specimens, our targeted genotyping assay accurately detected hematologic malignancies with 57.6% sensitivity and 100% specificity (95% confidence interval [CI]: 44.1% to 70.4% and 87.2% to 100%, respectively). MYD88 and TERT promoter mutations were prospectively identified in DNA extracts of CSF obtained from patients with PCNSL and glioblastoma, respectively, within 80 minutes. Across 132 specimens, hallmark mutations indicating the presence of malignancy were detected with 65.8% sensitivity and 100% specificity (95% CI: 56.2%-74.5% and 83.9%-100%, respectively). This targeted genotyping approach offers a rapid, scalable adjunct to reduce diagnostic and treatment delays in PCNSL.
Assuntos
Neoplasias do Sistema Nervoso Central , Técnicas de Genotipagem , Linfoma não Hodgkin , Mutação , Proteínas de Neoplasias , Reação em Cadeia da Polimerase em Tempo Real , Adulto , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/genética , Feminino , Humanos , Linfoma não Hodgkin/líquido cefalorraquidiano , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/genética , Proteínas de Neoplasias/líquido cefalorraquidiano , Proteínas de Neoplasias/genéticaRESUMO
The aryl hydrocarbon receptor (AhR) participates in the differentiation of mouse regulatory T cells (T(reg) cells) and interleukin 17 (IL-17)-producing helper T cells (T(H)17 cells), but its role in human T cell differentiation is unknown. We investigated the role of AhR in the differentiation of human induced T(reg) cells (iT(reg) cells). We found that AhR activation promoted the differentiation of CD4(+)Foxp3(-) T cells, which produce IL-10 and control responder T cells through granzyme B. However, activation of AhR in the presence of transforming growth factor-beta1 induced Foxp3(+) iT(reg) cells, which suppress responder T cells through the ectonucleoside triphosphate diphosphohydrolase CD39. The induction of functional Foxp3(+) iT(reg) cells required coordinated action of the transcriptional regulators Smad1 and Aiolos. Thus, AhR is a potential target through which functional iT(reg) cells could be induced in human autoimmune disorders.
Assuntos
Fatores de Transcrição Forkhead/imunologia , Ativação Linfocitária/imunologia , Receptores de Hidrocarboneto Arílico/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Regiões Promotoras Genéticas , Linfócitos T/citologiaRESUMO
Type 1 regulatory T cells (Tr1 cells ) that produce interleukin 10 (IL-10) are instrumental in the prevention of tissue inflammation, autoimmunity and graft-versus-host disease. The transcription factor c-Maf is essential for the induction of IL-10 by Tr1 cells, but the molecular mechanisms that lead to the development of these cells remain unclear. Here we show that the ligand-activated transcription factor aryl hydrocarbon receptor (AhR), which was induced by IL-27, acted in synergy with c-Maf to promote the development of Tr1 cells. After T cell activation under Tr1-skewing conditions, the AhR bound to c-Maf and promoted transactivation of the Il10 and Il21 promoters, which resulted in the generation of Tr1 cells and the amelioration of experimental autoimmune encephalomyelitis. Manipulating AhR signaling could therefore be beneficial in the resolution of excessive inflammatory responses.
Assuntos
Diferenciação Celular/imunologia , Regulação da Expressão Gênica , Proteína Oncogênica v-maf/imunologia , Receptores de Hidrocarboneto Arílico/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Cultivadas , Interleucinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/efeitos dos fármacosRESUMO
The immune response is normally controlled by regulatory T cells (Tregs). However, Treg deficits are found in autoimmune diseases, and therefore the induction of functional Tregs is considered a potential therapeutic approach for autoimmune disorders. The activation of the ligand-activated transcription factor aryl hydrocarbon receptor by 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) or other ligands induces dendritic cells (DCs) that promote FoxP3(+) Treg differentiation. Here we report the use of nanoparticles (NPs) to coadminister ITE and a T-cell epitope from myelin oligodendrocyte glycoprotein (MOG)(35)(-55) to promote the generation of Tregs by DCs. NP-treated DCs displayed a tolerogenic phenotype and promoted the differentiation of Tregs in vitro. Moreover, NPs carrying ITE and MOG(35-55) expanded the FoxP3(+) Treg compartment and suppressed the development of experimental autoimmune encephalomyelitis, an experimental model of multiple sclerosis. Thus, NPs are potential new tools to induce functional Tregs in autoimmune disorders.
Assuntos
Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/terapia , Bainha de Mielina/imunologia , Nanopartículas/química , Nanotecnologia/métodos , Animais , Doenças Autoimunes/imunologia , Citocinas/metabolismo , Epitopos/química , Epitopos de Linfócito T/química , Genes Reporter , Humanos , Sistema Imunitário/fisiologia , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão/métodos , Microssomos Hepáticos/metabolismo , Esclerose Múltipla/metabolismo , Linfócitos T Reguladores/citologiaRESUMO
The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) participates in the differentiation of FoxP3(+) T(reg), Tr1 cells, and IL-17-producing T cells (Th17). Most of our understanding on the role of AHR on the FoxP3(+) T(reg) compartment results from studies using the toxic synthetic chemical 2,3,7,8-tetrachlorodibenzo-p-dioxin. Thus, the physiological relevance of AHR signaling on FoxP3(+) T(reg) in vivo is unclear. We studied mice that carry a GFP reporter in the endogenous foxp3 locus and a mutated AHR protein with reduced affinity for its ligands, and found that AHR signaling participates in the differentiation of FoxP3(+) T(reg) in vivo. Moreover, we found that treatment with the endogenous AHR ligand 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) given parenterally or orally induces FoxP3(+) T(reg) that suppress experimental autoimmune encephalomyelitis. ITE acts not only on T cells, but also directly on dendritic cells to induce tolerogenic dendritic cells that support FoxP3(+) T(reg) differentiation in a retinoic acid-dependent manner. Thus, our work demonstrates that the endogenous AHR ligand ITE promotes the induction of active immunologic tolerance by direct effects on dendritic and T cells, and identifies nontoxic endogenous AHR ligands as potential unique compounds for the treatment of autoimmune disorders.
Assuntos
Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/prevenção & controle , Receptores de Hidrocarboneto Arílico/metabolismo , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Compartimento Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Tolerância Imunológica/efeitos dos fármacos , Indóis/metabolismo , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos dos fármacos , Tiazóis/metabolismo , Tretinoína/farmacologiaRESUMO
Interleukin (IL)-22 produced by innate lymphoid cells (ILCs) and CD4+ T cells plays an important role in host defence and mucosal homeostasis, thus it is important to investigate the mechanisms that regulate IL-22 production. We investigated the regulation IL-22 production by CD4+ T cells. Here we show that IL-21 triggers IL-22, but not IL-17 production by CD4+ T cells. STAT3, activated by IL-21, controls the epigenetic status of the il22 promoter and its interaction with the aryl hydrocarbon receptor (AhR). Moreover, IL-21 and AhR signalling in T cells control IL-22 production and the development of dextran sodium sulphate-induced colitis in ILC-deficient mice. Thus, we have identified IL-21 as an inducer of IL-22 production in CD4+ T cells in vitro and in vivo.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Interleucinas/biossíntese , Interleucinas/fisiologia , Perfilação da Expressão Gênica , Humanos , Interleucinas/genética , Interleucinas/metabolismo , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição STAT3/fisiologia , Transcrição Gênica , Interleucina 22RESUMO
BACKGROUND: Jawed vertebrates generate their immune-receptor repertoire by a recombinatorial mechanism that has the potential to produce harmful autoreactive lymphocytes. In mammals, peripheral tolerance to self-antigens is enforced by Foxp3(+) regulatory T cells. Recombinatorial mechanisms also operate in teleosts, but active immunoregulation is thought to be a late incorporation to the vertebrate lineage. METHODS/PRINCIPAL FINDINGS: Here we report the characterization of adaptive autoimmunity and Foxp3-based immunoregulation in the zebrafish. We found that zebrafish immunization with an homogenate of zebrafish central nervous system (zCNS) triggered CNS inflammation and specific antibodies. We cloned the zebrafish ortholog for mammalian Foxp3 (zFoxp3) which induced a regulatory phenotype on mouse T cells and controlled IL-17 production in zebrafish embryos. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate the acquisition of active mechanisms of self-tolerance early in vertebrate evolution, suggesting that active regulatory mechanisms accompany the development of the molecular potential for adaptive autoimmunity. Moreover, they identify the zebrafish as a tool to study the molecular pathways controlling adaptive immunity.