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1.
Kidney Int ; 98(2): 391-403, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32622525

RESUMO

Focal segmental glomerulosclerosis (FSGS) is a common cause of steroid-resistant nephrotic syndrome. Spontaneous remission of FSGS is rare and steroid-resistant FSGS frequently progresses to renal failure. Many inheritable forms of FSGS have been described, caused by mutations in proteins that are important for podocyte function. Here, we show that a basic leucine zipper transcription factor, MafB, protects against FSGS. MAFB expression was found to be decreased in the podocytes of patients with FSGS. Moreover, conditional podocyte-specific MafB-knockout mice developed FSGS with massive proteinuria accompanied by depletion of the slit diaphragm-related proteins (Nphs1 and Magi2), and the podocyte-specific transcription factor Tcf21. These findings indicate that MafB plays a crucial role in the pathogenesis of FSGS. Consistent with this, adriamycin-induced FSGS and attendant proteinuria were ameliorated by MafB overexpression in the podocytes of MafB podocyte-specific transgenic mice. Thus, MafB could be a new therapeutic target for FSGS.


Assuntos
Glomerulosclerose Segmentar e Focal , Síndrome Nefrótica , Podócitos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Glomerulosclerose Segmentar e Focal/genética , Humanos , Fator de Transcrição MafB/genética , Camundongos , Camundongos Transgênicos , Síndrome Nefrótica/genética , Proteinúria/genética , Proteinúria/prevenção & controle
2.
Am J Respir Cell Mol Biol ; 61(4): 525-536, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30965014

RESUMO

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease characterized by peripheral airways inflammation and emphysema. Emerging evidence indicates a contribution of both innate and adaptive immune cells to the development of COPD. Transcription factor T-bet modulates the function of immune cells and therefore might be involved in the pathogenesis of COPD. To elucidate the role for T-bet in elastase-induced emphysema, pathological phenotypes were compared between wild-type and T-bet-/- mice. T-bet-/- mice demonstrated enhanced emphysema development on histological analyses, with higher values of mean linear intercept and dynamic compliance relative to wild-type mice. The number of neutrophils in BAL fluids, lung IL-6 and IL-17 expression, and the proportion of CD4+ T cells positive for IL-17 or retinoic acid receptor-related orphan receptor-γt were higher in T-bet-/- mice than in wild-type mice. Although T-bet downregulates cytokine expression in bone marrow-derived macrophages and MH-S cells, a murine alveolar cell line, depending on the surrounding environment, IL-6 expression in alveolar macrophages isolated from elastase-treated mice was not dependent on T-bet. Coculture of bone marrow-derived macrophages and CD4+ T cells revealed that T-bet regulation of IL-17 expression was dependent on CD4+ T cells. Neutralizing antibodies against IL-6R or IL-17 ameliorated the development of emphysema in T-bet-/- mice. In conclusion, we demonstrate that T-bet ameliorates elastase-induced emphysema formation by modulating the host immune response in the lungs.


Assuntos
Enfisema Pulmonar/imunologia , Proteínas com Domínio T/fisiologia , Imunidade Adaptativa , Animais , Líquido da Lavagem Broncoalveolar/citologia , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/imunologia , Quimiotaxia de Leucócito , Citocinas/metabolismo , Feminino , Imunidade Inata , Pulmão/imunologia , Pulmão/metabolismo , Subpopulações de Linfócitos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neutrófilos/fisiologia , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/análise , Elastase Pancreática/toxicidade , Fenótipo , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/genética , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas com Domínio T/deficiência , Proteínas com Domínio T/genética
3.
Kidney Int ; 93(1): 54-68, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28964572

RESUMO

The transcription factor MafB is essential for development of the parathyroid glands, the expression of which persists after morphogenesis and in adult parathyroid glands. However, the function of MafB in adult parathyroid tissue is unclear. To investigate this, we induced chronic kidney disease (CKD) in wild-type and MafB heterozygote (MafB+/-) mice by feeding them an adenine-supplemented diet, leading to secondary hyperparathyroidism. The elevated serum creatinine and blood urea nitrogen levels in heterozygous and wild-type mice fed the adenine-supplemented diet were similar. Interestingly, secondary hyperparathyroidism, characterized by serum parathyroid hormone elevation and enlargement of parathyroid glands, was suppressed in MafB+/- mice fed the adenine-supplemented diet compared to similarly fed wild-type littermates. Quantitative RT-PCR and immunohistochemical analyses showed that the increased expression of parathyroid hormone and cyclin D2 in mice with CKD was suppressed in the parathyroid glands of heterozygous CKD mice. A reporter assay indicated that MafB directly regulated parathyroid hormone and cyclin D2 expression. To exclude an effect of a developmental anomaly in MafB+/- mice, we analyzed MafB tamoxifen-induced global knockout mice. Hypocalcemia-stimulated parathyroid hormone secretion was significantly impaired in MafB knockout mice. RNA-sequencing analysis indicated PTH, Gata3 and Gcm2 depletion in the parathyroid glands of MafB knockout mice. Thus, MafB appears to play an important role in secondary hyperparathyroidism by regulation of parathyroid hormone and cyclin D2 expression. Hence, MafB may represent a new therapeutic target in secondary hyperparathyroidism.


Assuntos
Hiperparatireoidismo Secundário/metabolismo , Fator de Transcrição MafB/metabolismo , Glândulas Paratireoides/metabolismo , Animais , Nitrogênio da Ureia Sanguínea , Cálcio/sangue , Creatinina/sangue , Ciclina D2/genética , Ciclina D2/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hiperparatireoidismo Secundário/sangue , Hiperparatireoidismo Secundário/genética , Hiperparatireoidismo Secundário/patologia , Hipocalcemia/genética , Hipocalcemia/metabolismo , Fator de Transcrição MafB/deficiência , Fator de Transcrição MafB/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Glândulas Paratireoides/patologia , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/genética
4.
Front Immunol ; 8: 1399, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163480

RESUMO

c-Maf belongs to the large Maf family of transcription factors and plays a key role in the regulation of cytokine production and differentiation of TH2, TH17, TFH, and Tr1 cells. Invariant natural killer T (iNKT) cells can rapidly produce large quantity of TH-related cytokines such as IFN-γ, IL-4, and IL-17A upon stimulation by glycolipid antigens, such as α-galactosylceramide (α-GalCer). However, the role of c-Maf in iNKT cells and iNKT cells-mediated diseases remains poorly understood. In this study, we demonstrate that α-GalCer-stimulated iNKT cells express c-Maf transcript and protein. By using c-Maf-deficient fetal liver cell-reconstituted mice, we further show that c-Maf-deficient iNKT cells produce less IL-17A than their wild-type counterparts after α-GalCer stimulation. While c-Maf deficiency does not affect the development and activation of iNKT cells, c-Maf is essential for the induction of IL-17-producing iNKT (iNKT17) cells by IL-6, TGF-ß, and IL-1ß, and the optimal expression of RORγt. Accordingly, c-Maf-deficient iNKT17 cells lose the ability to recruit neutrophils into the lungs. Taken together, c-Maf is a positive regulator for the expression of IL-17A and RORγt in iNKT17 cells. It is a potential therapeutic target in iNKT17 cell-mediated inflammatory disease.

5.
Sci Rep ; 7(1): 10496, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28874814

RESUMO

Intracerebral Theiler's murine encephalomyelitis virus (TMEV) infection in mice induces inflammatory demyelination in the central nervous system. Although C57BL/6 mice normally resistant to TMEV infection with viral clearance, we have previously demonstrated that RORγt-transgenic (tg) C57BL/6 mice, which have Th17-biased responses due to RORγt overexpression in T cells, became susceptible to TMEV infection with viral persistence. Here, using T-bet-tg C57BL/6 mice and Gata3-tg C57BL/6 mice, we demonstrated that overexpression of T-bet, but not Gata3, in T cells was detrimental in TMEV infection. Unexpectedly, T-bet-tg mice died 2 to 3 weeks after infection due to failure of viral clearance. Here, TMEV infection induced splenic T cell depletion, which was associated with lower anti-viral antibody and T cell responses. In contrast, Gata3-tg mice remained resistant, while Gata3-tg mice had lower IFN-γ and higher IL-4 production with increased anti-viral IgG1 responses. Thus, our data identify how overexpression of T-bet and Gata3 in T cells alters anti-viral immunity and confers susceptibility to TMEV infection.


Assuntos
Fator de Transcrição GATA3/genética , Expressão Gênica , Poliomielite/genética , Poliomielite/virologia , Proteínas com Domínio T/genética , Theilovirus/fisiologia , Animais , Biomarcadores , Citocinas/metabolismo , Doenças Desmielinizantes/genética , Suscetibilidade a Doenças , Fator de Transcrição GATA3/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Poliomielite/imunologia , Poliomielite/metabolismo , Baço/imunologia , Baço/metabolismo , Proteínas com Domínio T/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Virulência , Replicação Viral
6.
Mol Cell Biol ; 37(12)2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28320875

RESUMO

Allelic exclusion describes the essential immunological process by which feedback repression of sequential DNA rearrangements ensures that only one autosome expresses a functional T or B cell receptor. In wild-type mammals, approximately 60% of cells have recombined the DNA of one T cell receptor ß (TCRß) V-to-DJ-joined allele in a functional configuration, while the second allele has recombined only the DJ sequences; the other 40% of cells have recombined the V to the DJ segments on both alleles, with only one of the two alleles predicting a functional TCRß protein. Here we report that the transgenic overexpression of GATA3 leads predominantly to biallelic TCRß gene (Tcrb) recombination. We also found that wild-type immature thymocytes can be separated into distinct populations based on intracellular GATA3 expression and that GATA3LO cells had almost exclusively recombined only one Tcrb locus (that predicted a functional receptor sequence), while GATA3HI cells had uniformly recombined both Tcrb alleles (one predicting a functional and the other predicting a nonfunctional rearrangement). These data show that GATA3 abundance regulates the recombination propensity at the Tcrb locus and provide new mechanistic insight into the historic immunological conundrum for how Tcrb allelic exclusion is mediated.


Assuntos
Alelos , Fator de Transcrição GATA3/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Animais , Fator de Transcrição GATA3/genética , Regulação da Expressão Gênica , Ontologia Genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Mutação/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Baço/metabolismo , Timócitos/metabolismo , Recombinação V(D)J/genética
7.
PLoS One ; 11(1): e0147064, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26784959

RESUMO

Mycobacterium avium complex (MAC) is the most common cause of nontuberculous mycobacterial disease in humans. The role of Th17 immunity in the pathogenesis of intracellular bacteria, such as MAC, is not currently understood. Transcription factor RAR-related orphan receptor gamma t (RORγt) is known as the master regulator for Th17 cell development. Here, we investigated the role of RORγt in host responses against MAC infection. Wild-type (WT) mice and RORγt-overexpressing mice were infected with MAC via intratracheal inoculation. Systemic MAC growth was not different between WT mice and RORγt-overexpressing mice. However, neutrophilic pulmonary inflammation following MAC infection was enhanced in RORγt-overexpressing mice compared with that in WT mice. The cytokine expression shifted toward a Th17 phenotype in the lungs of RORγt-overexpressing mice following MAC infection; the levels of IL-6 and IL-17 were significantly higher in the lung of these mice than in WT mice. In addition to the increase in IL-17 single-positive T cells, T cells producing both IL-17 and interferon-γ were elevated in the lung of RORγt-overexpressing mice following MAC infection. These findings suggest that RORγt overexpression-mediated Th17 bias contributes to local inflammation rather than systemic responses, by regulating neutrophil recruitment into the sites of infection during MAC infection.


Assuntos
Infecção por Mycobacterium avium-intracellulare/complicações , Mycobacterium avium/patogenicidade , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/fisiologia , Pneumonia/etiologia , Animais , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/microbiologia , Pneumonia/metabolismo , Pneumonia/patologia , Reação em Cadeia da Polimerase em Tempo Real
8.
Exp Anim ; 64(4): 353-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26156402

RESUMO

Encapsulating peritoneal sclerosis is one of the most serious complications of long-term peritoneal dialysis. The pathogenesis of encapsulating peritoneal sclerosis has not been elucidated, but several putative factors necessary for the development of peritoneum fibrosis (PF) have been reported. However, the roles of T helper (Th) cells in the progression of PF are unknown. The purpose of this study was to clarify the roles of Th1, Th2, and Th17 cells in the progression of PF. T-bet, GATA-3, and RORγt are Th1, Th2, and Th17 lineage commitment transcription factors, respectively. We previously generated Th1-biased (T-bet transgenic (Tg)) mice, Th2-biased (GATA-3 Tg) mice, and Th17-biased (RORγt Tg) mice. In this study, Th1, Th2, Th17-biased, and wild-type mice were administered chlorhexidine gluconate (CG) intraperitoneally and analyzed on day 21. CG-injected GATA-3 Tg mice showed a distended intestinal tract and developed marked thickening of the submesothelial space compared with the other groups. CG-injected GATA-3 Tg mice also showed significant expression of α-SMA positive cells, macrophages, and collagen III in the submesothelium. In contrast, CG-injected T-bet Tg mice only developed mild peritoneal fibrosis. Cytokines analysis in peritoneal fluid showed that IFN-γ was significantly increased in CG-injected T-bet Tg mice and that IL-13 was significantly increased in CG-injected GATA-3 Tg mice. Moreover, intraperitoneal administration of IFN-γ improved PF in GC-injected wild-type mice. Our results suggest that Th2 cells may play roles in the development of experimental PF and that Th1 cells may alleviate the severity of experimental PF.


Assuntos
Fator de Transcrição GATA3/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Fibrose Peritoneal/genética , Proteínas com Domínio T/genética , Células Th1/fisiologia , Células Th17/fisiologia , Células Th2/fisiologia , Animais , Líquido Ascítico/metabolismo , Clorexidina/análogos & derivados , Progressão da Doença , Interferon gama/metabolismo , Interleucina-13/metabolismo , Camundongos Transgênicos , Diálise Peritoneal/efeitos adversos , Fibrose Peritoneal/induzido quimicamente , Fibrose Peritoneal/etiologia , Índice de Gravidade de Doença , Linfócitos T
9.
Arthritis Res Ther ; 17: 105, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25928901

RESUMO

INTRODUCTION: Differentiation of T helper 17 cells is dependent on the expression of transcription retinoid-related orphan receptor gamma t (RORγt). The purpose of our study is to determine the role of RORγt expression in T cells on the development of collagen-induced arthritis (CIA). METHODS: CIA was induced in C57BL/6 and T cell-specific RORγt transgenic (RORγt Tg) mice. At day 10 post-1st-immunization, lymph node (LN) cells were cultured with type II collagen (CII), and the expression levels of various cytokines and transcription factors on CD4+ T cells were measured. Total cells or CD4+ cells of draining LN were harvested from each mouse group after CII-immunization and transferred into C57BL/6 mice, and then CIA was induced in recipient mice. The expression levels of RORγt and other surface antigens, and the production of cytokines were analyzed in forkhead box P3 (Foxp3)+ regulatory T (Treg) cells. Foxp3+ Treg cells were analyzed for suppressive activity against proliferation of effector CD4+ T cells. Interlukin (IL)-10 neutralizing antibody was administrated in the course of CIA. RESULTS: CIA was significantly suppressed in RORγt Tg mice compared with C57BL/6 mice. RORγt expression and IL-17 production were significantly higher in CII-reactive CD4+ T cells from RORγt Tg mice. Arthritis was significantly attenuated in C57BL/6 mice recipient of cells from RORγt Tg mice. Most of Foxp3+ Treg cells expressed RORγt, produced IL-10 but not IL-17, and overexpressed CC chemokine receptor 6 (CCR6) and surface antigens related to the suppressive activity of Foxp3+ Treg cells in RORγt Tg mice. In vitro suppression assay demonstrated significant augmentation of the suppressive capacity of Foxp3+ Treg cells in RORγt Tg mice. CIA was exacerbated in both C57BL/6 mice and RORγt Tg mice by the treatment of anti-IL-10 antibody. CONCLUSION: Our results indicated that RORγt overexpression in T cells protected against the development of CIA. The protective effects were mediated, at least in part, through the anti-inflammatory effects including high production of IL-10 of RORγt+Foxp3+ Treg cells.


Assuntos
Artrite Experimental/genética , Doenças Autoimunes/genética , Regulação da Expressão Gênica , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , RNA/genética , Animais , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Diferenciação Celular , Células Cultivadas , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T Reguladores/imunologia
10.
Blood ; 125(2): 370-82, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25349175

RESUMO

Although overexpression of T-bet, a master transcription factor in type-1 helper T lymphocytes, has been reported in several hematologic and immune diseases, its role in their pathogenesis is not fully understood. In the present study, we used transgenic model mice (T-bet(tg/wt) and T-bet(tg/tg)) to investigate the effects of T-bet overexpression selectively in T lymphocytes on the development of hematologic and immune diseases. The results showed that T-bet overexpression in T cells spontaneously induced maturation arrest in the mononuclear phagocyte lineage, as well as spontaneous dermatitis and pulmonary alveolar proteinosis (PAP)-like disease in T-bet(tg/wt) and T-bet(tg/tg) mice, respectively. T-bet(tg/tg) alveoli with the PAP phenotype showed remarkable reorganization of alveolar mononuclear phagocyte subpopulations and impaired function, in addition to augmented T-cell infiltration. In addition, PAP development in T-bet(tg/tg) mice was found to be associated with increased migration of myeloid cells from the bone marrow into the peripheral blood. These findings reveal an unexpected link between T-bet overexpression in T lymphocytes and the development of PAP caused by reorganization of mononuclear phagocytes in the lung, and provide new insight into the molecular pathogenesis of secondary PAP accompanied by hematologic disorders.


Assuntos
Hematopoese/imunologia , Macrófagos/imunologia , Células Mieloides/imunologia , Proteinose Alveolar Pulmonar/imunologia , Proteínas com Domínio T/biossíntese , Animais , Citometria de Fluxo , Imuno-Histoquímica , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas com Domínio T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
11.
Brain Behav Immun ; 43: 86-97, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25046854

RESUMO

In a viral model for multiple sclerosis (MS), Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD), both immune-mediated tissue damage (immunopathology) and virus persistence have been shown to cause pathology. T helper (Th) 17 cells are a Th cell subset, whose differentiation requires the transcription factor retinoic acid-related orphan receptor (ROR) γt, secrete pro-inflammatory cytokines, including IL-17, and can antagonize Th1 cells. Although Th17 cells have been shown to play a pathogenic role in immune-mediated diseases or a protective role in bacterial and fungal infections, their role in viral infections is unclear. Using newly established Th17-biased RORγt Tg mice, we tested whether Th17 cells could play a pathogenic or protective role in TMEV-IDD by contributing to immunopathology and/or by modulating anti-viral Th1 immune responses. While TMEV-infected wild-type littermate C57BL/6 mice are resistant to TMEV-IDD, RORγt Tg mice developed inflammatory demyelinating lesions with virus persistence in the spinal cord. TMEV-infected RORγt Tg mice had higher levels of IL-17, lower levels of interferon-γ, and fewer CD8(+) T cells, without alteration in overall levels of anti-viral lymphoproliferative and antibody responses, compared with TMEV-infected wild-type mice. This suggests that a Th17-biased "gain-of-function" mutation could increase susceptibility to virus-mediated demyelinating diseases.


Assuntos
Modelos Animais de Doenças , Esclerose Múltipla/imunologia , Medula Espinal/imunologia , Células Th17/imunologia , Theilovirus/imunologia , Animais , Suscetibilidade a Doenças , Camundongos , Camundongos Transgênicos , Esclerose Múltipla/patologia , Esclerose Múltipla/virologia , Medula Espinal/patologia
12.
J Neuroimmunol ; 276(1-2): 142-9, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25288300

RESUMO

Th17 cells play an important role in multiple sclerosis (MS) and its autoimmune model, experimental autoimmune encephalomyelitis (EAE). However, studies have not addressed how enhanced Th17 immune responses can affect demyelinating diseases. We induced EAE with MOG in RORγt transgenic C57BL/6 mice that overexpress a Th17 inducing transcription factor. RORγt transgenic mice developed more severe EAE than wild-type mice with more robust anti-MOG Th17 immune responses. In contrast, mice overexpressing T-bet, a Th1-inducing transcription factor, were resistant to EAE. Therefore, a genetic bias toward Th17 immune responses could contribute to CNS immunopathology.


Assuntos
Sistema Nervoso Central/patologia , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sistema Nervoso Central/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/genética , Citometria de Fluxo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Esclerose Múltipla/induzido quimicamente , Proteínas com Domínio T/genética , Células Th1/patologia
13.
Exp Anim ; 63(2): 133-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24770638

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease, and its pathogenesis includes genetic, environmental, and immunological factors, such as T helper cells and their secreted cytokines. T helper cells are classified as Th1, Th2, and Th17 cells. However, it is unclear which T helper cells are important in UC. Dextran sulfate sodium (DSS)-induced colitis is a commonly used model of UC. In this study, we induced DSS colitis in Th1 dominant (T-bet transgenic (Tg)) mice, Th2 dominant (GATA-3 Tg) mice, and Th17 dominant (RORγt Tg) mice to elucidate the roles of T helper cell in DSS colitis. The results showed that GATA-3 Tg mice developed the most severe DSS colitis compared with the other groups. GATA-3 Tg mice showed a significant decreased in weight from day 1 to day 7, and an increased high score for the disease activity index compared with the other groups. Furthermore, GATA-3 Tg mice developed many ulcers in the colon, and many neutrophils and macrophages were detected on day 4 after DSS treatment. Measurement of GATA-3-induced cytokines demonstrated that IL-13 was highly expressed in the colon from DSS-induced GATA-3 Tg mice. In conclusion, GATA-3 overexpression in T-cells and IL-13 might play important roles in the development of DSS colitis.


Assuntos
Colite Ulcerativa/genética , Fator de Transcrição GATA3/genética , Expressão Gênica/genética , Células Th1 , Células Th17 , Células Th2 , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Interleucina-13/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
14.
J Am Soc Nephrol ; 25(11): 2546-57, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24722438

RESUMO

We previously showed that the transcription factor Mafb is essential for podocyte differentiation and foot process formation. Podocytes are susceptible to injury in diabetes, and this injury leads to progression of diabetic nephropathy. In this study, we generated transgenic mice that overexpress Mafb in podocytes using the nephrin promoter/enhancer. To examine a potential pathogenetic role for Mafb in diabetic nephropathy, Mafb transgenic mice were treated with either streptozotocin or saline solution. Diabetic nephropathy was assessed by renal histology and biochemical analyses of urine and serum. Podocyte-specific overexpression of Mafb had no effect on body weight or blood glucose levels in either diabetic or control mice. Notably, albuminuria and changes in BUN levels and renal histology observed in diabetic wild-type animals were ameliorated in diabetic Mafb transgenic mice. Moreover, hyperglycemia-induced downregulation of Nephrin was mitigated in diabetic Mafb transgenic mice, and reporter assay results suggested that Mafb regulates Nephrin directly. Mafb transgenic glomeruli also overexpressed glutathione peroxidase, an antioxidative stress enzyme, and levels of the oxidative stress marker 8-hydroxydeoxyguanosine decreased in the urine of diabetic Mafb transgenic mice. Finally, Notch2 expression increased in diabetic glomeruli, and this effect was enhanced in diabetic Mafb transgenic glomeruli. These data indicate Mafb has a protective role in diabetic nephropathy through regulation of slit diaphragm proteins, antioxidative enzymes, and Notch pathways in podocytes and suggest that Mafb could be a therapeutic target.


Assuntos
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Fator de Transcrição MafB/genética , Podócitos/fisiologia , Animais , Apoptose/fisiologia , Glicemia/metabolismo , Peso Corporal/fisiologia , Linhagem Celular Transformada , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Expressão Gênica/fisiologia , Glutationa Peroxidase/metabolismo , Hiperglicemia/genética , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Insulina/sangue , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Podócitos/patologia , Regiões Promotoras Genéticas/genética , Receptor Notch2/metabolismo , Transdução de Sinais/fisiologia
15.
J Exp Med ; 211(3): 563-77, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24516120

RESUMO

Trail(+)DX5(-)Eomes(-) natural killer (NK) cells arise in the mouse fetal liver and persist in the adult liver. Their relationships with Trail(-)DX5(+) NK cells remain controversial. We generated a novel Eomes-GFP reporter murine model to address this question. We found that Eomes(-) NK cells are not precursors of classical Eomes(+) NK cells but rather constitute a distinct lineage of innate lymphoid cells. Eomes(-) NK cells are strictly dependent on both T-bet and IL-15, similarly to NKT cells. We observed that, in the liver, expression of T-bet in progenitors represses Eomes expression and the development of Eomes(+) NK cells. Reciprocally, the bone marrow (BM) microenvironment restricts T-bet expression in developing NK cells. Ectopic expression of T-bet forces the development of Eomes(-) NK cells, demonstrating that repression of T-bet is essential for the development of Eomes(+) NK cells. Gene profile analyses show that Eomes(-) NK cells share part of their transcriptional program with NKT cells, including genes involved in liver homing and NK cell receptors. Moreover, Eomes(-) NK cells produce a broad range of cytokines, including IL-2 and TNF in vitro and in vivo, during immune responses against vaccinia virus. Thus, mutually exclusive expression of T-bet and Eomes drives the development of different NK cell lineages with complementary functions.


Assuntos
Medula Óssea/metabolismo , Linhagem da Célula/imunologia , Células Matadoras Naturais/imunologia , Fígado/metabolismo , Nicho de Células-Tronco/imunologia , Proteínas com Domínio T/metabolismo , Transferência Adotiva , Animais , Diferenciação Celular/imunologia , Primers do DNA/genética , Citometria de Fluxo , Técnicas de Introdução de Genes , Células Matadoras Naturais/citologia , Camundongos , Análise em Microsséries , Modelos Animais , Reação em Cadeia da Polimerase em Tempo Real , Proteínas com Domínio T/genética
16.
Int J Mol Sci ; 15(2): 1700-18, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24463292

RESUMO

T helper (Th)2 cells have been proposed to play a neuroprotective role in multiple sclerosis (MS). This is mainly based on "loss-of-function" studies in an animal model for MS, experimental autoimmune encephalomyelitis (EAE), using blocking antibodies against Th2 related cytokines, and knockout mice lacking Th2-related molecules. We tested whether an increase of Th2 responses ("gain-of-function" approach) could alter EAE, the approach of novel GATA binding protein 3 (GATA3)-transgenic (tg) mice that overexpress GATA3, a transcription factor required for Th2 differentiation. In EAE induced with myelin oligodendrocyte glycoprotein (MOG)35-55 peptide, GATA3-tg mice had a significantly delayed onset of disease and a less severe maximum clinical score, compared with wild-type C57BL/6 mice. Histologically, GATA3-tg mice had decreased levels of meningitis and demyelination in the spinal cord, and anti-inflammatory cytokine profiles immunologically, however both groups developed similar levels of MOG-specific lymphoproliferative responses. During the early stage, we detected higher levels of interleukin (IL)-4 and IL-10, with MOG and mitogen stimulation of regional lymph node cells in GATA3-tg mice. During the late stage, only mitogen stimulation induced higher IL-4 and lower interferon-γ and IL-17 production in GATA3-tg mice. These results suggest that a preexisting bias toward a Th2 immune response may reduce the severity of inflammatory demyelinating diseases, including MS.


Assuntos
Fator de Transcrição GATA3/genética , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Células Th2/imunologia , Células Th2/metabolismo , Animais , Complexo CD3/metabolismo , Citocinas/metabolismo , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Feminino , Fator de Transcrição GATA3/metabolismo , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Esclerose Múltipla/metabolismo , Mutação , Glicoproteína Mielina-Oligodendrócito/imunologia , Medula Espinal/imunologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
17.
J Immunol ; 192(4): 1707-17, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24446514

RESUMO

Th1 immune responses are thought to be important in protection against intracellular pathogens. T-bet is a critical regulator for Th1 cell differentiation and Th1 cytokine production. The aim of this study was to determine the role of T-bet in host defense against Mycobacterium avium complex (MAC) infection. Wild-type mice, T-bet-deficient mice, and T-bet-overexpressing mice were infected with MAC via intratracheal inoculation. Macrophages and dendritic cells obtained from these mice were incubated with MAC. T-bet-deficient mice were highly susceptible to MAC, compared with wild-type mice and T-bet-overexpressing mice. Neutrophilic pulmonary inflammation was also enhanced in T-bet-deficient mice, but attenuated in T-bet-overexpressing mice, following MAC infection. Cytokine expression shifted toward Th1 in the lung and spleen of T-bet-overexpressing mice, but toward Th17 in T-bet-deficient mice. IFN-γ supplementation to T-bet-deficient mice reduced systemic MAC growth but did not reduce pulmonary inflammation. In contrast, neutralization of IL-17 in T-bet-deficient mice reduced pulmonary inflammation but did not affect mycobacterial growth in any organs tested. T-bet-deficient T cells tended to differentiate toward Th17 cells in vitro following exposure to MAC. Treatment with NO donor suppressed MAC-induced Th17 cell differentiation of T-bet-deficient T cells. This study identified that the fine balance between Th1 and Th17 responses is essential in defining the outcome of MAC disease. T-bet functions as a regulator for Th1/Th17 balance and is a critical determinant for host resistance to MAC infection by controlling cytokine and NO levels.


Assuntos
Infecção por Mycobacterium avium-intracellulare/imunologia , Proteínas com Domínio T/metabolismo , Células Th1/imunologia , Células Th17/imunologia , Animais , Diferenciação Celular , Células Dendríticas/imunologia , Modelos Animais de Doenças , Feminino , Inflamação/imunologia , Interferon gama/metabolismo , Interleucina-17/imunologia , Interleucina-6/metabolismo , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Complexo Mycobacterium avium/crescimento & desenvolvimento , Complexo Mycobacterium avium/imunologia , Neutrófilos/imunologia , Óxido Nítrico/metabolismo , Baço/imunologia , Proteínas com Domínio T/deficiência , Proteínas com Domínio T/genética
18.
Clin Exp Nephrol ; 18(5): 697-703, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24198050

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a major global problem and is also associated with a decreased health-related quality of life (HRQOL). The aim of this study was to evaluate measured HRQOL based on the new CKD classification including proteinuria stage, and the effect of measured HRQOL on CKD progression and clinical outcomes over a 3-year period. METHODS: EuroQol (EQ-5D), a generic preference-based questionnaire, was administered to 537 CKD outpatients at the University of Tsukuba Hospital between November and December 2008. We evaluated disease progression in CKD patients including the incidence of end-stage kidney disease (ESKD), cardiovascular disease (CVD) and all-cause mortality over a 3-year follow-up period. RESULTS: The proportions progressing to the higher stages were 32.6, 20.0, 36.6, 39.5, and 45.8 % from glomerular filtration rate (GFR) stages (G) 1-4, respectively. The proportion progressing to ESKD (G5D) was 0.7 % from G2, 3.9 % from G3b, 20.8 % from G4 and 63.4 % from G5. The incidence of CVD and/or death was 1.2, 4.6, 4.9, 5.3, 8.3 and 21.1 % from G1-G5, respectively. The quality-adjustment weights at G4-5 were significantly lower than at G1-2 and the weights at proteinuria stage (A) 3 were significantly lower than at A1-2. The quality-adjustment weights of patients with events such as 50 % estimated GFR decline, dialysis, CVD, and/or death were significantly lower than those without events. CONCLUSION: We showed CKD progression and clinical outcomes over a 3-year period. Quality-adjustment weights in CKD patients were associated with not only disease progression such as initiation of dialysis treatment and incidence of CVD events and all-cause death, but also the level of proteinuria at baseline.


Assuntos
Proteinúria/epidemiologia , Qualidade de Vida , Progressão da Doença , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteinúria/diagnóstico , Diálise Renal , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia
19.
J Immunol ; 190(3): 1056-65, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23293351

RESUMO

In refractory asthma, neutrophils, rather than eosinophils, often predominate in the airways. Neutrophilic airway inflammation appears to be resistant to steroids and may be related to the Th17, rather than the Th2, cytokine milieu. However, the role of GATA-3 and RORγt, transcription factors for Th2 and Th17 cell differentiation, respectively, in the pathogenesis of steroid-insensitive asthma remains unclear. To examine the effect of GATA-3- and RORγt-overexpression backgrounds on airway inflammation and steroid sensitivity, we generated two strains of transgenic mice overexpressing GATA-3 or RORγt. Mice were sensitized and challenged with OVA. Some OVA-sensitized/challenged mice were treated with dexamethasone, anti-IL-17 Ab, CXCR2 antagonist, or anti-IL-6R Ab to demonstrate their therapeutic effects on airway inflammation. Although Ag-specific airway inflammation and hyperresponsiveness were induced in each mouse, the phenotype of inflammation showed a distinct difference that was dependent upon the genotype. GATA-3-overexpressing mice exhibited steroid-sensitive eosinophilic inflammation with goblet cell hyperplasia and mucus hyperproduction under Th2-biased conditions, and RORγt-overexpressing mice developed steroid-insensitive neutrophilic inflammation under Th17-biased conditions. The levels of keratinocyte-derived chemokine, MIP-2, IL-6, and other neutrophil chemotaxis-related mediators were significantly elevated in OVA-exposed RORγt-overexpressing mice compared with wild-type mice. Interestingly, airway hyperresponsiveness accompanied by neutrophilic airway inflammation in RORγt-overexpressing mice was effectively suppressed by anti-IL-17 Ab, CXCR2 antagonist, or anti-IL-6R Ab administration. In conclusion, our results suggest that the expression levels of GATA-3 and RORγt may be important for determining the phenotype of asthmatic airway inflammation. Furthermore, blockade of the Th17-signaling pathway may be a treatment option for steroid-insensitive asthma.


Assuntos
Asma/genética , Fator de Transcrição GATA3/fisiologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/fisiologia , Células Th17/imunologia , Células Th2/imunologia , Animais , Asma/imunologia , Quimiocinas/biossíntese , Quimiocinas/genética , Modelos Animais de Doenças , Feminino , Fator de Transcrição GATA3/biossíntese , Fator de Transcrição GATA3/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Interleucina-17/antagonistas & inibidores , Interleucina-17/fisiologia , Pulmão/imunologia , Pulmão/patologia , Linfocinas/biossíntese , Linfocinas/genética , Linfopoese/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neutrófilos/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/biossíntese , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Ovalbumina/imunologia , Ovalbumina/toxicidade , Fenótipo , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/fisiologia , Células Th17/metabolismo , Células Th2/metabolismo
20.
Eur J Immunol ; 42(8): 1999-2009, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22623033

RESUMO

Retinoic acid related orphan receptor gamma-t (RORγt) is known to be a master regulator of Th17-cell development. In this study, we generated RORγt-overexpressing transgenic (RORγt Tg) mice in which transgene expression was driven by the CD2 promoter, and found that these mice developed polyclonal plasmacytosis and autoantibody production. RORγt Tg mice were generated on a C57BL/6 background, and also were intercrossed with BALB/c mice. BALB/c F1 (BALB/F1) RORγt Tg mice developed massive polyclonal plasma-cytosis, and had shorter life spans. Splenomegaly and infiltration of plasma cells into the lung were observed. Hyperglobulinemia, anti-double-stranded DNA antibodies, anti-erythrocyte antibodies, and anti-platelet antibodies were detected in BALB/F1 RORγt Tg mice. In the present study, polyclonal plasmacytosis in BALB/F1 RORγt Tg mice appeared to be due to the induction of excessive IL-6 production by IL-17. We detected increased numbers of CD11b(+) cells that produced IL-6. We also generatedIL-6-deficient RORγt Tg BALB/F1 background mice, which displayed high levels of serum IL-17, but did not develop severe hyperglobulinemia. Excessive IL-6 production by several cell types, including macrophages, in BALB/F1 RORγt Tg mice, might effect the development of plasma-cytosis. These results suggest that RORγt plays important roles in the development of plasmacytosis and autoantibody production.


Assuntos
Autoanticorpos/biossíntese , Interleucina-17/biossíntese , Interleucina-6/biossíntese , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Plasmócitos/fisiologia , Regiões Promotoras Genéticas , Animais , Plaquetas/imunologia , Antígeno CD11b/biossíntese , Antígenos CD2/genética , DNA/imunologia , Eritrócitos/imunologia , Interleucina-17/sangue , Interleucina-17/metabolismo , Interleucina-6/deficiência , Interleucina-6/genética , Pulmão/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Púrpura Hiperglobulinêmica/imunologia , Esplenomegalia/imunologia
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