Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Biol Chem ; 292(1): 205-216, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-27872193

RESUMO

Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor that plays a crucial role in protection of cells from electrophile-induced toxicity through up-regulating phase II detoxifying enzymes and phase III transporters. We previously reported that oxidative stress induces up-regulation of interleukin-11 (IL-11), a member of the IL-6 family that ameliorates acetaminophen-induced liver toxicity. However, a role for IL-11 in protection of cells from electrophile-induced toxicity remains unclear. Here we show that an environmental electrophile, 1,2-naphthoquinone (1,2-NQ), but not 15d-prostaglandin J2 (PGJ2) or tert-butylhydroxyquinone (tBHQ), induced IL-11 production. Consistent with a crucial role for prolonged ERK activation in H2O2-induced IL-11 production, 1,2-NQ, but not 15d-PGJ2 or tBHQ, elicited prolonged ERK activation. Conversely, inhibition of the ERK pathway by a MEK inhibitor completely blocked 1,2-NQ-induced IL-11 production at both protein and mRNA levels, further substantiating an intimate cross-talk between ERK activation and 1,2-NQ-induced IL-11 production. Promoter analysis of the Il11 gene revealed that two AP-1 sites were essential for 1,2-NQ-induced promoter activities. Among various members of the AP-1 family, Fra-1 was up-regulated by 1,2-NQ, and its up-regulation was blocked by a MEK inhibitor. Although NRF2 was not required for H2O2-induced IL11 up-regulation, NRF2 was essential for 1,2-NQ-induced IL11 up-regulation by increasing Fra-1 proteins possibly through promoting mRNA translation of FOSL1 Finally, intraperitoneal administration of 1,2-NQ induced body weight loss in wild-type mice, which was further exacerbated in Il11ra1-/- mice compared with Il11ra1+/- mice. Together, both Fra-1 and NRF2 play crucial roles in IL-11 production that protects cells from 1,2-NQ intestinal toxicity.


Assuntos
Interleucina-11/biossíntese , Enteropatias/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Naftoquinonas/toxicidade , Peritonite/prevenção & controle , Prostaglandina D2/análogos & derivados , Animais , Antineoplásicos/toxicidade , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Subunidade alfa de Receptor de Interleucina-11/fisiologia , Enteropatias/induzido quimicamente , Enteropatias/metabolismo , Enteropatias/patologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Peritonite/induzido quimicamente , Peritonite/metabolismo , Peritonite/patologia , Prostaglandina D2/toxicidade , Espécies Reativas de Oxigênio/metabolismo
2.
Hepatology ; 65(1): 237-252, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27770461

RESUMO

Tissue-resident macrophages and bone marrow (BM)-derived monocytes play a crucial role in the maintenance of tissue homeostasis; however, their contribution to recovery from acute tissue injury is not fully understood. To address this issue, we generated an acute murine liver injury model using hepatocyte-specific Cflar-deficient (CflarHep-low ) mice. Cellular FLICE-inhibitory protein expression was down-regulated in Cflar-deficient hepatocytes, which thereby increased susceptibility of hepatocytes to death receptor-induced apoptosis. CflarHep-low mice developed acute hepatitis and recovered with clearance of apoptotic hepatocytes at 24 hours after injection of low doses of tumor necrosis factor α (TNFα), which could not induce hepatitis in wild-type (WT) mice. Depletion of Kupffer cells (KCs) by clodronate liposomes did not impair clearance of dying hepatocytes or exacerbate hepatitis in CflarHep-low mice. To elucidate the roles of BM-derived monocytes and neutrophils in clearance of apoptotic hepatocytes, we examined the effect of depletion of these cells on TNFα-induced hepatitis in CflarHep-low mice. We reconstituted CflarHep-low mice with BM cells from transgenic mice in which human diphtheria toxin receptor (DTR) was expressed under control of the lysozyme M (LysM) promoter. TNFα-induced infiltration of myeloid cells, including monocytes and neutrophils, was completely ablated in LysM-DTR BM-reconstituted CflarHep-low mice pretreated with diphtheria toxin, whereas KCs remained present in the livers. Under these experimental conditions, LysM-DTR BM-reconstituted CflarHep-low mice rapidly developed severe hepatitis and succumbed within several hours of TNFα injection. We found that serum interleukin-6 (IL-6), TNFα, and histone H3 were aberrantly increased in LysM-DTR BM-reconstituted, but not in WT BM-reconstituted, CflarHep-low mice following TNFα injection. CONCLUSION: These findings indicate an unexpected role of myeloid cells in decreasing serum IL-6, TNFα, and histone H3 levels via the suppression of TNFα-induced hepatocyte apoptosis. (Hepatology 2017;65:237-252).


Assuntos
Hepatite/sangue , Hepatite/etiologia , Histonas/sangue , Células Mieloides/fisiologia , Animais , Apoptose , Progressão da Doença , Hepatócitos , Células de Kupffer , Camundongos , Camundongos Transgênicos , Fator de Necrose Tumoral alfa/fisiologia
3.
Liver Int ; 38(1): 59-67, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28557143

RESUMO

BACKGROUND & AIMS: We investigated the correlation between histological characteristics and changes in liver stiffness (LS) in patients with sustained virological response (SVR) using acoustic radiation force impulse (ARFI) elastography. METHODS: In this prospective study, we enrolled 176 hepatitis C patients with SVR who underwent ARFI elastography and liver biopsy before antiviral treatment, and serial ARFI elastography at the end of treatment (EOT) and at 24 weeks after the EOT. To compare the long-term changes in LS in patients with SVR using ARFI elastography, another group of 140 patients who had undergone paired biopsy after achieving SVR was included. RESULTS: Mean LS values were 1.60±0.63 m/s, 1.48±0.56 m/s and 1.37±0.62 m/s at baseline, EOT and 24 weeks after EOT, respectively, P<.001. Higher inflammatory activity at baseline was associated with an improvement in LS at the EOT, with an odds ratio of 1.940. Significant fibrosis at baseline was associated with an improvement in LS at 24 weeks after the EOT, with an odds ratio of 2.617. Among patients in the paired biopsy group with baseline fibrosis stage identical to the ARFI group, LS values at 24 weeks after the EOT did not show any difference with values at 5 years after EOT. CONCLUSIONS: Pre-treatment histological characteristics influence LS reduction after SVR is achieved.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatite C/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Resposta Viral Sustentada , Idoso , Antivirais/uso terapêutico , Biópsia , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Fígado/efeitos dos fármacos , Fígado/virologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
4.
J Immunol ; 191(9): 4562-72, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24068667

RESUMO

T cell Ig and mucin domain (TIM)-4 is involved in immune regulation. However, the pathological function of TIM-4 has not been understood and remains to be clarified in various disease models. In this study, DBA/1 mice were treated with anti-TIM-4 mAb during the induction or effector phase of collagen-induced arthritis (CIA). Anti-TIM-4 treatment in the induction phase exacerbated the development of CIA. In vitro experiments suggest that CD4 T cells bind to TIM-4 on APCs, which induces inhibitory effect to CD4 T cells. In contrast, therapeutic treatment with anti-TIM-4 mAb just before or after the onset or even at later stage of CIA significantly suppressed the development and progression by reducing proinflammatory cytokines in the ankle joints without affecting T or B cell responses. Consistently, clinical arthritis scores of collagen Ab-induced arthritis, which is not mediated by T or B cells, were significantly reduced in anti-TIM-4-treated mice with a concomitant decrease of proinflammatory cytokines in the joints. In vitro, macrophages secreted proinflammatory cytokines in response to TIM-4-Ig protein and LPS, which were reduced by the anti-TIM-4 mAb. The anti-TIM-4 mAb also inhibited the differentiation and bone-resorbing activity of osteoclasts. These results indicate that TIM-4 has two distinct functions depending on the stage of arthritis. The therapeutic effect of anti-TIM-4 mAb on arthritis is mediated by the inhibition of proinflammatory cytokine production by inflammatory cells, osteoclast differentiation, and bone resorption, suggesting that TIM-4 might be an appropriate target for the therapeutic treatment of arthritis.


Assuntos
Anticorpos Monoclonais/imunologia , Artrite Experimental/imunologia , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Animais , Anticorpos Monoclonais/uso terapêutico , Células Apresentadoras de Antígenos/imunologia , Linfócitos B/imunologia , Reabsorção Óssea/imunologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Colágeno , Citocinas/biossíntese , Lipopolissacarídeos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos Knockout , Osteoclastos/efeitos dos fármacos , Osteoclastos/imunologia
5.
J Enzyme Inhib Med Chem ; 30(6): 981-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26147347

RESUMO

The single-crystal structure of anagliptin, N-[2-({2-[(2S)-2-cyanopyrrolidin-1-yl]-2-oxoethyl}amino)-2-methylpropyl]-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxamide, was determined. Two independent molecules were held together by intermolecular hydrogen bonds, and the absolute configuration of the 2-cyanopyrrolidine ring delivered from l-prolinamide was confirmed to be S. The interactions of anagliptin with DPP-4 were clarified by the co-crystal structure solved at 2.85 Å resolution. Based on the structure determined by X-ray crystallography, the potency and selectivity of anagliptin were discussed, and an SAR study using anagliptin derivatives was performed.


Assuntos
Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Cristalografia por Raios X , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/isolamento & purificação , Inibidores da Dipeptidil Peptidase IV/síntese química , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/síntese química , Relação Estrutura-Atividade
6.
Pediatr Int ; 56(6): 873-883, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24750209

RESUMO

BACKGROUND: Although pediatric inflammatory bowel disease (IBD) is characterized by extensive intestinal involvement and rapid early progression, the precise cause and specific factors involved in disease aggravation have not been well established. The aim of this study was to investigate the pathogenesis of pediatric IBD. METHODS: The expression of inflammatory molecules in colon samples taken from active ulcerative colitis (UC) and Crohn's disease (CD) patients was compared with those of controls. Three children each with UC and CD in both the active and remission phase and their controls were enrolled, and the inflammatory gene expression in the mucosa was examined by microarray. Additionally, six children from each group were further enrolled in a real-time reverse transcription polymerase chain reaction and an immunohistochemical study to examine the expression of CXCL9, 10, 11, CXCR3, matrix metalloproteinase (MMP)-1, -3, -7, and -10. RESULTS: The microarray analysis revealed enhanced expression of the CXCL9, 10, and 11 genes in the active phase of CD. The expression of MMP-1, -3, -7, and -10 was significantly enhanced in the active phase of UC. These changes were also confirmed by real-time reverse transcription polymerase chain reaction. Immunohistochemical analysis revealed enhanced expression of CXCL9, 10, and 11 in both the lamina propria and epithelial cells in these patients. CXCR3-positive cells were also confirmed in the lamina propria. The expression of MMP-1, -3, -7, and -10 was also enhanced in the mucosal epithelial cells and the lamina propria in both CD and UC patients. CONCLUSIONS: These findings suggest that CXCR3 axis components and MMP play an important role in the mucosal damage in pediatric IBD.


Assuntos
Quimiocinas CXC/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Metaloproteinases da Matriz/metabolismo , Receptores CXCR3/metabolismo , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/patologia , Masculino
7.
J Heart Lung Transplant ; 43(8): 1348-1357, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38657776

RESUMO

BACKGROUND: Transplantation of human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) has emerged as a promising therapy to treat end-stage heart failure. However, the immunogenicity of hiPS-CMs in transplanted patients has not been fully elucidated. Thus, in vivo models are required to estimate immune responses against hiPS-CMs in transplant recipients. METHODS: We transferred human peripheral blood mononuclear cells (hPBMCs) into NOD/Shi-scid IL-2rgnull (NOG) MHC class I/II double knockout (NOG-ΔMHC) mice, which were reported to accept hPBMCs without xenogeneic-graft-versus-host disease (xeno-GVHD). Then, hiPS-CM sheets generated from the hiPS cell line 201B7 harboring a luciferase transgene were transplanted into the subcutaneous space of NOG-ΔMHC mice. Graft survival was monitored by bioluminescent images using a Xenogen In Vivo Imaging System. RESULTS: The human immune cells were engrafted for more than 3 months in NOG-ΔMHC mice without lethal xeno-GVHD. The hiPS-CMs expressed a moderate level of human leukocyte antigen (HLA)-class I, but not HLA-class II, molecules even after interferon-gamma (IFN-γ) stimulation. Consistently, the allogenic IFN-γ-treated hiPS-CMs induced weak CD8+ but not CD4+ T cell responses in vitro. hiPS-CM sheets disappeared approximately 17 to 24 days after transplantation in hPBMC-transferred NOG-ΔMHC mice, and CD8+ T cell depletion significantly prolonged graft survival, similar to what was observed following tacrolimus treatment. CONCLUSIONS: hiPS-CMs are less immunogenic in vitro but induce sufficient CD8+ T cell-mediated immune responses for graft rejection in vivo.


Assuntos
Linfócitos T CD8-Positivos , Rejeição de Enxerto , Células-Tronco Pluripotentes Induzidas , Leucócitos Mononucleares , Camundongos Knockout , Miócitos Cardíacos , Animais , Humanos , Camundongos , Rejeição de Enxerto/imunologia , Linfócitos T CD8-Positivos/imunologia , Camundongos SCID , Camundongos Endogâmicos NOD , Modelos Animais de Doenças , Sobrevivência de Enxerto
8.
Langmuir ; 29(25): 8164-9, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23734978

RESUMO

We identified the mechanism of the formation of needle-shaped microcrystals on which the contact angle of a water droplet exceeds 170° [Nishikawa, N. et al. Langmuir, 2012, 28, 17817-17824]. The standing needle-shaped crystal of the closed-ring isomer of a diarylethene 3c grew at a much lower temperature than the eutectic temperature by irradiation of UV light on the thin films of the open-ring isomer 3o, due to the epitaxial growth of the 013 plane of 3c over the 110 plane of the crystal lattice of 3o in the subphase. Therefore, the new crystal-growth mechanism triggered by the photoisomerization does not require special inorganic single-crystal substrates and may be called self-epitaxial crystal growth. The needle-shaped crystals appeared well-ordered and stood inclined at an angle of about 60° to the surface. Consequently, the photo-induced rough surface shows not only the superhydrophobic lotus effect, but also the antireflection moth-eye effect, and these effects were switchable by alternate irradiation with UV and visible light.


Assuntos
Cristalização , Etilenos/química , Fotoquímica/métodos , Interações Hidrofóbicas e Hidrofílicas , Temperatura , Raios Ultravioleta
9.
Nat Med ; 12(6): 693-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16680149

RESUMO

Tumor-cell apoptosis is the basis of many cancer therapies, and tumor-specific T cells are the principal effectors of successful antitumor immunotherapies. Here we show that induction of tumor-cell apoptosis by an agonistic monoclonal antibody to DR5, the apoptosis-inducing receptor for TNF-related apoptosis-inducing ligand (TRAIL), combined with T-cell activation by agonistic monoclonal antibodies to the costimulatory molecules CD40 and CD137, potently and rapidly stimulated tumor-specific effector CD8+ T cells capable of eradicating preestablished tumors. Primary fibrosarcomas initiated with the carcinogen 3-methylcholanthrene (MCA), multiorgan metastases and a primary tumor containing as many as 90% tumor cells resistant to DR5-specific monoclonal antibody were rejected without apparent toxicity or induction of autoimmunity. This combination therapy of three monoclonal antibodies (trimAb) rapidly induced tumor-specific CD8+ T cells producing interferon (IFN)-gamma in the tumor-draining lymph node, consistent with a crucial requirement for CD8+ T cells and IFN-gamma in the tumor rejection process. These results in mice indicate that a rational monoclonal antibody-based therapy that both causes tumor-cell apoptosis through DR5 and activates T cells may be an effective strategy for cancer immunotherapy in humans.


Assuntos
Anticorpos Monoclonais , Neoplasias , Receptores do Fator de Necrose Tumoral/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Interferon gama/genética , Interferon gama/imunologia , Ativação Linfocitária , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos SCID , Transplante de Neoplasias , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Receptores do Fator de Necrose Tumoral/genética , Taxa de Sobrevida , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/imunologia
10.
Biol Pharm Bull ; 36(12): 1902-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292050

RESUMO

When carbohydrate metabolism is impaired, fatty acid metabolism is activated. Excess acetyl-coenzyme A (CoA) is generated from fatty acids by ß-oxidation and is used for the formation of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) and subsequently for acetoacetate. High levels of secreted ketone bodies (acetoacetate and 3ß-hydroxybutyrate) lower the pH of blood and urine, resulting in ketoacidosis. HMG-CoA lyase in hepatic cells is a rate-limiting enzyme catalyzing the cleavage of HMG-CoA to acetoacetate, and thus inhibition of this enzyme results in reduced acetoacetate production, in other words, impaired ketoacidosis. Inhibition of HMG-CoA lyase activity possibly prevents ketoacidosis and should be the therapeutic target. Polyphenols are common and abundant dietary constituents with beneficial effects on human health. We examined the inhibitory effects of dietary polyphenols on HMG-CoA lyase activity in cellular extracts of human hepatoma HepG2 cells. Of the nine representative dietary polyphenols tested, (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), and gallic acid (GA) effectively inhibited HMG-CoA lyase activity. Lineweaver-Burk analysis revealed that EGC and EGCG are likely to be mixed-type noncompetitive inhibitors. Pyrogallol with the gallyl structure also inhibited HMG-CoA lyase activity, suggesting that the gallyl moiety of polyphenols is important for the inhibition of HMG-CoA lyase activity.


Assuntos
Oxo-Ácido-Liases/metabolismo , Polifenóis/farmacologia , Carcinoma Hepatocelular , Extratos Celulares , Células Hep G2 , Humanos , Neoplasias Hepáticas , Oxo-Ácido-Liases/antagonistas & inibidores
11.
J Biol Chem ; 286(50): 43383-93, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22020938

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/death receptor 5 (DR5)-mediated cell death plays an important role in the elimination of tumor cells and transformed cells. Recently, recombinant TRAIL and agonistic anti-DR5 monoclonal antibodies have been developed and applied to cancer therapy. However, depending on the type of cancer, the sensitivity to TRAIL has been reportedly different, and some tumor cells are resistant to TRAIL-mediated apoptosis. Using confocal microscopy, we found that large amounts of DR5 were localized in the nucleus in HeLa and HepG2 cells. Moreover, these tumor cells were resistant to TRAIL, whereas DU145 cells, which do not have nuclear DR5, were highly sensitive to TRAIL. By means of immunoprecipitation and Western blot analysis, we found that DR5 and importin ß1 were physically associated, suggesting that the nuclear DR5 was transported through the nuclear import pathway mediated by importin ß1. Two functional nuclear localization signals were identified in DR5, the mutation of which abrogated the nuclear localization of DR5 in HeLa cells. Moreover, the nuclear transport of DR5 was also prevented by the knockdown of importin ß1 using siRNA, resulting in the up-regulation of DR5 expression on the cell surface and an increased sensitivity of HeLa and HepG2 cells to TRAIL. Taken together, our findings suggest that the importin ß1-mediated nuclear localization of DR5 limits the DR5/TRAIL-induced cell death of human tumor cells and thus can be a novel target to improve cancer therapy with recombinant TRAIL and anti-DR5 antibodies.


Assuntos
Morte Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , beta Carioferinas/metabolismo , Western Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Células HeLa , Células Hep G2 , Humanos , Microscopia Confocal , Ligação Proteica/efeitos dos fármacos , Transporte Proteico , RNA Interferente Pequeno , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , beta Carioferinas/genética
12.
Cell Immunol ; 274(1-2): 26-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22425227

RESUMO

We examined the effects of nicotine on differentiation and function of monocyte-derived human dendritic cells (DCs). NiDCs, which were the DCs differentiated in the presence of nicotine, showed lower levels of CD1a. Secretion of IL-12 and TNF-α by lipopolysaccharide (LPS)-stimulated NiDCs was significantly suppressed compared to monocyte-derived DCs grown without nicotine. NiDCs displayed a diminished capacity to induce allogeneic T cell proliferation with a reduced production of IFN-γ, and maintained/enhanced LPS-mediated expression of coinhibitory molecules. Interestingly, NiDCs enhanced the expression of nuclear receptor peroxisome proliferator-activated receptors γ (PPAR γ), which has immunomodulatory properties. Expression of PPAR γ and PPAR γ-target genes was significantly inhibited by pretreatment with d-tubocurarine, antagonist of non-selective nicotinic acetylcholine receptors (nAChR). In addition, reduction of Th1 responses was inhibited after blocking nAChR-mediated signal. These data suggest the effect of nicotine on altering DC immunogenicity by impeding Th1 immunity is partially mediated by upregulation of PPAR γ.


Assuntos
Células Dendríticas/imunologia , Ativação Linfocitária/efeitos dos fármacos , Nicotina/farmacologia , PPAR gama/biossíntese , Receptores Nicotínicos/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Interferon gama/biossíntese , Interleucina-12/biossíntese , Interleucina-12/metabolismo , Lipopolissacarídeos/imunologia , Monócitos/metabolismo , Antagonistas Nicotínicos/farmacologia , PPAR gama/genética , Fenótipo , Fumar/efeitos adversos , Fumar/imunologia , Células Th1/imunologia , Células Th2/imunologia , Tubocurarina/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
13.
Langmuir ; 28(51): 17817-24, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23198739

RESUMO

A superhydrophobic surface on which the contact angle of a water droplet exceeds 170° was reversibly produced by alternate irradiation with UV and visible light. Superhydrophobicity is due to the formation of densely generated submicrometer sized needle-shaped crystals (less than 0.2-0.3 µm diameter and 2.2-2.5 µm long) at 30 °C, which is much lower than the eutectic temperature of either isomers of the diarylethene. Below the eutectic temperature, the generated crystals were much smaller than those generated above the eutectic temperature. These smaller crystals more effectively enhanced the superhydrophobicity.


Assuntos
Hidrocarbonetos Aromáticos/química , Interações Hidrofóbicas e Hidrofílicas , Processos Fotoquímicos , Água/química , Propriedades de Superfície , Temperatura
14.
J Immunol ; 184(10): 5493-501, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20400706

RESUMO

The blockade of immune suppression against antitumor responses is a particularly attractive strategy when combined with agents that promote tumor-specific CTLs. In this study, we have attempted to further improve the CTL induction and potent antitumor efficacy of a combination mAb-based therapy (termed "trimAb therapy") that comprises tumor cell death-inducing anti-death receptor 5 mAb and immune activating anti-CD40 and anti-CD137 mAbs. Among trimAb-treated tumors, the infiltration of CD4(+) Foxp3(+) cells was greater in progressing tumors compared with stable tumors. Blockade of CTLA-4 (CD152)-mediated signals by an antagonistic mAb substantially increased the tumor rejection rate of trimAb therapy, although the immune responses of draining lymph node cells were not augmented. Interestingly, by comparison, additional treatment with agonistic anti-glucocorticoid-induced TNF receptor mAb, antagonistic anti-programmed death-1 (CD279) mAb, or agonistic anti-OX40 (CD134) mAb significantly augmented immune responses of draining lymph node cells, but did not augment the therapeutic effect of trimAb. CD4 T cell depletion reduced the antitumor effect of anti-CTLA-4 mAb treatment alone, but did not reduce the tumor rejection rate of trimAb in conjunction with anti-CTLA-4 mAb. Thus, the blockade of the CTLA-4-mediated inhibitory signal in tumor infiltrating CTL may be the most effective strategy to augment the effect of immune therapies that generate tumor-specific CTL.


Assuntos
Anticorpos Bloqueadores/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/terapia , Animais , Anticorpos Bloqueadores/fisiologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/fisiologia , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Superfície/imunologia , Proteínas Reguladoras de Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Antígeno CTLA-4 , Citotoxicidade Imunológica , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/patologia , Ativação Linfocitária/imunologia , Depleção Linfocítica , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Receptor de Morte Celular Programada 1 , Transporte Proteico/imunologia , Receptores de Fator de Crescimento Neural/imunologia , Receptores OX40/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia
15.
Eur J Oral Sci ; 120(5): 408-14, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22984998

RESUMO

Tobacco smoking is a significant risk factor for periodontal diseases. Nicotine, one of the most studied constituents in cigarette smoke, is thought to modify immune responses. Dendritic cells (DCs), which are key mediators between innate and adaptive immunity, stimulate naive T cells to differentiate to effector T-cell subsets that may be actively involved in the immunopathogenesis of periodontal diseases. In this study, we evaluated the effects of nicotine and lipopolysaccharide (LPS) from Porphyromonas gingivalis, alone and in combination, on the functions of human monocyte-derived DCs to elucidate the mechanism of tissue destruction of smoking-associated periodontal diseases. P. gingivalis LPS-stimulated DCs differentiated with nicotine (NiDCs) induced lower T-cell proliferation and human leukocyte antigen (HLA)-DR expression, but elevated expression of programmed cell death ligand 1. Additionally, NiDCs impaired interferon-γ production but maintained interleukin (IL)-5 and IL-10 production in co-cultured T cells. Furthermore, NiDCs produced lower levels of proinflammatory cytokines compared with DCs differentiated in the absence of nicotine. Interestingly, NiDCs preferentially produced the T helper 2 (Th2)-type chemokines macrophage chemotactic protein-1 and macrophage-derived chemokine. These results suggest that the presence of nicotine during differentiation of DCs modulates the immunoregulatory functions of P. gingivalis LPS-stimulated DCs.


Assuntos
Citocinas/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Lipopolissacarídeos/imunologia , Nicotina/farmacologia , Doenças Periodontais/etiologia , Porphyromonas gingivalis/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Análise de Variância , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/imunologia , Citometria de Fluxo , Humanos , Lipopolissacarídeos/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Nicotina/metabolismo , Doenças Periodontais/imunologia , Porphyromonas gingivalis/metabolismo , Subpopulações de Linfócitos T/metabolismo
16.
J Allergy Clin Immunol ; 127(5): 1267-76.e6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21333342

RESUMO

BACKGROUND: Autophagy plays a crucial role in controlling various biological responses including starvation, homeostatic turnover of long-lived proteins, and invasion of bacteria. However, a role for autophagy in development and/or function of mast cells is unknown. OBJECTIVE: To investigate a role for autophagy in mast cells, we generated bone marrow-derived mast cells (BMMCs) from mice lacking autophagy related gene (Atg) 7, an essential enzyme for autophagy induction. METHODS: Bone marrow-derived mast cells were generated from bone marrow cells of control and IFN-inducible Atg7-deficient mice, and morphologic and functional analyses were performed. RESULTS: We found that conversion of type I to type II light chain (LC3)-II, a hallmark of autophagy, was constitutively induced in mast cells under full nutrient conditions, and LC3-II localized in secretory granules of mast cells. Although deletion of Atg7 did not impair the development of BMMCs, Atg7(-/-) BMMCs showed severe impairment of degranulation, but not cytokine production on FcεRI cross-linking. Intriguingly, LC3-II but not LC3-I was co-localized with CD63, a secretory lysosomal marker, and was released extracellularly along with degranulation in Atg7(+/+) but not Atg7(-/-) BMMCs. Moreover, passive cutaneous anaphylaxis reactions were severely impaired in mast cell-deficient WBB6F1-W/W(V) mice reconstituted with Atg7(-/-) BMMCs compared with Atg7(+/+) BMMCs. CONCLUSION: These results suggest that autophagy is not essential for the development but plays a crucial role in degranulation of mast cells. Thus, autophagy might be a potential target to treat allergic diseases in which mast cells are critically involved.


Assuntos
Autofagia/fisiologia , Degranulação Celular/fisiologia , Mastócitos/fisiologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Proteína 7 Relacionada à Autofagia , Humanos , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Glicoproteínas da Membrana de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/metabolismo , Vesículas Secretórias/metabolismo , Tetraspanina 30
17.
Biomed Rep ; 17(4): 83, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36158316

RESUMO

Bile acids are strongly associated with the pathogenesis of functional gastrointestinal diseases. In recent years, blue laser imaging (BLI) endoscopy has emerged as a novel image-enhanced endoscopic method, which illustrates bile as a reddish hue. The present study investigated the factors that affect the area of bile in duodenal bulbs using BLI. For this purpose, patients (356 cases) who underwent upper endoscopy with BLI between April, 2017 and December, 2019, and completed patient background and symptom questionnaires [Constipation Scoring System (CSS), Bristol Stool Form Scale (BSFS) and Frequency Scale for Symptoms of gastroesophageal reflux disease (FSSG)], were retrospectively investigated. Each BLI bile score was calculated as a percentage of bile area in a field of view in the duodenal bulb using a KS400 image analysis system, and the association with abdominal symptoms was examined using multiple regression analysis. The patient characteristics included the following: Age (in years), 69.9±11.3; male/female ratio, 146/210; body mass index, 23.0±3.8; reflux esophagitis (M/A/B/C), 143/19/3/3; atrophic gastritis (C-0/C1-3/O1-3), 132/100/124; proton pump inhibitor potassium competitive acid blocker/aspirin/ursodeoxycholic acid/gall bladder stones/cholecystectomy, 105/27/18/43/18; BLI bile score, 7.10 (±14.34); CSS score, 3.55 (±3.80); BSFS score, 3.91 (±1.02); and FSSG score, 4.80 (±5.76). Correlation coefficients (P<0.05) for the BLI bile score were found for cholecystectomy (Rho=0.137) and aspirin use (Rho=0.118). In multiple regression analysis, independent predictors of the BLI bile score were cholecystectomy [standardized partial regression coefficient (ß)=0.169, P=0.001] and the BSFS score (ß=0.107, P=0.042). On the whole, the present study demonstrates that the duodenal bile area in BLI upper endoscopy is associated with cholecystectomy and fecal characteristics.

18.
Blood ; 113(16): 3821-30, 2009 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-19224762

RESUMO

Phagocytes such as macrophages and dendritic cells (DCs) engulf apoptotic cells to maintain peripheral immune tolerance. However, the mechanism for the recognition of dying cells by phagocytes is not fully understood. Here, we demonstrate that T-cell immunoglobulin mucin-3 (Tim-3) recognizes apoptotic cells through the FG loop in the IgV domain, and is crucial for clearance of apoptotic cells by phagocytes. Whereas Tim-4 is highly expressed on peritoneal resident macrophages, Tim-3 is expressed on peritoneal exudate macrophages, monocytes, and splenic DCs, indicating distinct Tim-mediated phagocytic pathways used by different phagocytes. Furthermore, phagocytosis of apoptotic cells by CD8(+) DCs is inhibited by anti-Tim-3 mAb, resulting in a reduced cross-presentation of dying cell-associated antigens in vitro and in vivo. Administration of anti-Tim-3 as well as anti-Tim-4 mAb induces autoantibody production. These results indicate a crucial role for Tim-3 in phagocytosis of apoptotic cells and cross-presentation, which may be linked to peripheral tolerance.


Assuntos
Apresentação de Antígeno/imunologia , Apoptose/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/fisiologia , Macrófagos Peritoneais/imunologia , Fagocitose/imunologia , Receptores Virais/imunologia , Animais , Anticorpos/farmacologia , Apresentação de Antígeno/efeitos dos fármacos , Antígenos CD8/imunologia , Linhagem Celular , Receptor Celular 2 do Vírus da Hepatite A , Tolerância Imunológica/efeitos dos fármacos , Camundongos , Ratos , Receptores Virais/antagonistas & inibidores
19.
Langmuir ; 27(10): 6395-400, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21504166

RESUMO

By alternate UV and visible light irradiation, reversible topographical changes were observed on a newly synthesized diarylethene microcrystalline surface between the rough crystalline surface of an open-ring isomer and flat eutectic surfaces. The contact angle changes of a water droplet between 80° and 150° and peak intensities changes of the open-ring isomer in XRD patterns within 2 h of repeating cycle were observed. The results indicated that reversibly photogenerated rod-shaped crystals on the surface were produced based on the lattice of the open-ring isomer crystals in the subphase.


Assuntos
Hidrocarbonetos Aromáticos/química , Raios Ultravioleta , Molhabilidade , Absorção , Temperatura
20.
Proc Natl Acad Sci U S A ; 105(31): 10895-900, 2008 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-18667695

RESUMO

Chronic cholestasis often results in premature death from liver failure with fibrosis; however, the molecular mechanisms contributing to biliary cirrhosis are not demonstrated. In this article, we show that the death signal mediated by TNF-related apoptosis-inducing ligand (TRAIL) receptor 2/death receptor 5 (DR5) may be a key regulator of cholestatic liver injury. Agonistic anti-DR5 monoclonal antibody treatment triggered cholangiocyte apoptosis, and subsequently induced cholangitis and cholestatic liver injury in a mouse strain-specific manner. TRAIL- or DR5-deficient mice were relatively resistant to common bile duct ligation-induced cholestasis, and common bile duct ligation augmented DR5 expression on cholangiocytes, sensitizing mice to DR5-mediated cholangitis. Notably, anti-DR5 monoclonal antibody-induced cholangitis exhibited the typical histological appearance, reminiscent of human primary sclerosing cholangitis. Human cholangiocytes constitutively expressed DR5, and TRAIL expression and apoptosis were significantly elevated in cholangiocytes of human primary sclerosing cholangitis and primary biliary cirrhosis patients. Thus, TRAIL/DR5-mediated apoptosis may substantially contribute to chronic cholestatic disease, particularly primary sclerosing cholangitis.


Assuntos
Apoptose/imunologia , Colangite/metabolismo , Colestase/imunologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Anticorpos Monoclonais , Linhagem Celular Tumoral , Colangite/patologia , Colestase/metabolismo , Colestase/patologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Mutantes , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA