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1.
Front Immunol ; 10: 1448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293595

RESUMO

Type I interferon (IFN-I) is induced during innate immune response and is required for initiating antiviral activity, growth inhibition, and immunomodulation. STAT1, STAT2, and STAT3 are activated in response to IFN-I stimulation. STAT1, STAT2, and IRF9 form ISGF3 complex which transactivates downstream IFN-stimulated genes and mediates antiviral response. However, the role of STAT3 remains to be characterized. Here, we review the multiple actions of STAT3 on suppressing IFN-I responses, including blocking IFN-I signaling, downregulating the expression of ISGF3 components, and antagonizing the transcriptional activity of ISGF3. Finally, we discuss the evolution of the suppressive activity of STAT3 and the therapeutic potential of STAT3 inhibitors in host defense against viral infections and IFN-I-associated diseases.


Assuntos
Interferon Tipo I/metabolismo , Fator de Transcrição STAT3/metabolismo , Viroses/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fator de Transcrição STAT3/genética , Transdução de Sinais/imunologia , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
2.
J Nanosci Nanotechnol ; 8(2): 828-33, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18464414

RESUMO

In this study, presents an innovative method for nanoparticle synthesis system for nanosized ZnO fabrication with powder or suspension type. The experimental device is primarily composed of a high frequency induction heating system, a pressure control system, a temperature control system and an automatic nanoparticle collection system. This study employs an automatic collection system with liquid nitrogen to condense and collect the nanoparticles. The influence of such process variables such as heating temperature and vacuum pressure are analyzed and compared through experimentation in order to identify the working conditions most conducive to the production of nanoparticles with smaller mean particle size. The prepared ZnO nanoparticles are characterized for nanostructural properties by the TEM and XRD. An Ultraviolet-Visible (UV-Vis) spectrophotometer is used to analyze the optical property of the nanoparticles. The ZnO nanofluid already has good dispersion, so even without dispersant, it can still remain in stable suspension for a fairly long time. Experimental results indicate that the particle size of produced ZnO nanoparticles is around 20 nm and with the production rate of 1.24 g/min.

3.
Front Immunol ; 9: 1886, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30158934

RESUMO

Type I interferon (IFN-I) is a pluripotent cytokine that modulates innate and adaptive immunity. We have previously shown that STAT3 suppresses IFN-I response in a manner dependent on its N-terminal domain (NTD), but independent of its DNA-binding and transactivation ability. Using the yeast two-hybrid system, we have identified phospholipid scramblase 2 (PLSCR2) as a STAT3 NTD-binding partner and a suppressor of IFN-I response. Overexpression of PLSCR2 attenuates ISRE-driven reporter activity, which is further aggravated by co-expression of STAT3. Moreover, PLSCR2 deficiency enhances IFN-I-induced gene expression and antiviral activity without affecting the activation or nuclear translocation of STAT1 and STAT2 or the assembly of ISGF3 complex. Instead, PLSCR2 impedes promoter occupancy by ISGF3, an effect further intensified by the presence of STAT3. Moreover, palmitoylation of PLSCR2 is required for its binding to STAT3 and for this suppressive activity. In addition to STAT3, PLSCR2 also interacts with STAT2, which facilitates the suppressive effect on ISGF3-mediated transcriptional activity. Together, these results define the role of a novel STAT3-PLSCR2 axis in fine-tuning IFN-I response.


Assuntos
Interferon Tipo I/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Citocinas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Modelos Biológicos , Proteínas de Transferência de Fosfolipídeos/genética , Ligação Proteica , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/genética , Técnicas do Sistema de Duplo-Híbrido
4.
Cancer Med ; 7(7): 3073-3083, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29905028

RESUMO

Conduct an accurate risk assessment of resected oral cavity squamous cell carcinoma (OSCC) patients by accessing a nationwide systemic investigation is pivotal to improve treatment outcomes. In this article, we tried to determine the impact of different prognostic factors for OSCC patients who received adjuvant radiotherapy (RT) after curative surgery, using Taiwan's national cancer registry database (TCR). A nationwide, large population-based study was conducted using TCR with patients identified from 2007 to 2015. The study variables included age, gender, cancer subsites, stage, histology grade, margin and extra-nodal extension (ENE) status, treatment type, surgery to RT interval (ORI), total RT treatment time (RTT), and RT dose. Univariate and multivariate analysis were performed to identify predictors of the variables associated with overall survival (OS), cause-specific survival (CSS), local-regional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS). 8986 OSCC patients treated with surgery and adjuvant RT were analyzed. In multivariate analysis, worse outcomes were associated with males, older age, subsite in the oral tongue, advanced stage, higher histologic grade, involved margin, and positive ENE. ORI only showed an adverse trend in LRFS, when exceeding 7 weeks (P = .06). RTT >8 weeks was a significant poor predictor in OS, CSS and LRFS (P < .001). Extreme RT dose (>70 Gy or ≤50 Gy) also demonstrated an adverse impact on the outcomes. Prolonged RT treatment time and extreme RT doses were identified as significantly poor prognostic predictors in OSCC patients who received adjuvant RT after curative surgery.

5.
Oncotarget ; 8(58): 98384-98393, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29228697

RESUMO

PURPOSE: In the current targeted therapy era, information on the effect of smoking in epidermal growth factor receptor (EGFR)-mutant lung cancer patients is scarce. RESULTS: In total, 11,678 adenocarcinoma patients were enrolled. Of these, 33.3% and 91.8% of male and female patients were non-smokers, respectively. An increased amount of smoking (P < 0.001 for trend), fewer smoke-free years (P < 0.001 for trend), and younger age of smoking initiation (P = 0.034 for trend) were all associated with significantly lower EGFR mutation rates. Smokers had a shorter median overall survival (OS) among both EGFR-mutant and EGFR-wild type patients (17.8 vs. 21.1 months, and 7.9 vs. 11.4 months respectively; both P < 0.001). Among patients with EGFR-mutant adenocarcinoma, younger smokers were associated with shorter OS (P = 0.047). In multivariate analysis, female gender was an independent prognostic factor for OS (hazard ratio: 0.86 [95% confidence interval {CI}: 0.80-0.93]; P < 0.001 in the EGFR-mutant group and 0.88 [95% CI: 0.81-0.96]; P = 0.004 in the EGFR-wild type group). MATERIALS AND METHODS: We reviewed the National Lung Cancer database (Taiwan) to assess the impact of smoking on the EGFR mutation rate and survival in advanced lung adenocarcinoma patients during 2011 and 2014 retrospectively. CONCLUSIONS: Smoking was associated with lower incidence of EGFR mutation rate and reduced OS of advanced lung adenocarcinoma patients in a dose-dependent manner. In addition to EGFR mutation and smoking, gender also plays an important role in survival among these patients.

6.
J Exp Med ; 213(13): 3025-3039, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27849553

RESUMO

Marginal zone B (MZ B) cells can rapidly produce antibody in response to infection with blood-borne encapsulated pathogens. Although TLR-mediated activation of MZ B is known to trigger humoral immune response, the signal cascade directing this response remains undefined. Here, we demonstrate that STAT1 plays an essential role in TLR-mediated antibody response of MZ B cells. Further, the TLR-induced IgM response is impaired in a type I and type II IFN-independent manner. Although activation, proliferation, and apoptosis are not affected, both differentiation into plasma cells and IgM production are impaired in Stat1-/- MZ B cells. Interestingly, STAT1 directly regulates the expression of Prdm1 (encodes BLIMP-1) by binding to its promoter, and Prdm1 expression is reduced in Stat1-/- MZ B cells. Restoration of BLIMP-1 to cells rescues TLR-induced IgM response. Moreover, Stat1-/- mice are more susceptible to S. pneumoniae infection, which can be rescued by the serum of bacteria-primed WT mice. The increased susceptibility to S. pneumoniae infection in Stat1-/- mice is also intrinsic to STAT1 requirement in MZ B cells. Collectively, these results define a differential regulation of TLR-mediated activation and differentiation of MZ B cells by STAT1 and reveal a STAT1-dependent, but IFN-independent, antibody response during infection and inflammation.


Assuntos
Linfócitos B/imunologia , Patógenos Transmitidos pelo Sangue , Diferenciação Celular/imunologia , Infecções Pneumocócicas/imunologia , Fator de Transcrição STAT1/imunologia , Streptococcus pneumoniae/imunologia , Animais , Linfócitos B/patologia , Diferenciação Celular/genética , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Interferons/genética , Interferons/imunologia , Camundongos , Camundongos Knockout , Infecções Pneumocócicas/genética , Infecções Pneumocócicas/patologia , Fator 1 de Ligação ao Domínio I Regulador Positivo , Fator de Transcrição STAT1/genética , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia
7.
Oncotarget ; 7(29): 46628-46635, 2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27191886

RESUMO

Lung cancer is relatively rare in young patients as the median age at diagnosis is 65-70 years. The main objective of this nationwide study was to investigate the characteristics of young lung cancer in Taiwan, especially the relationships among smoking behavior, epidermal growth factor receptor (EGFR) mutation, and age. The National Taiwan Lung Cancer Registry, a database contain detailed cancer statistics, was analyzed in this study for the period 2011-2012. Young lung cancer was defined as age ≦ 45 years. There were 21,536 lung cancer patients (13,187 men and 8349 women). Among these patients, 1074 (5.0%) were in the younger group, and 20,462 patients (95.0%) were in the older group. Female gender (48.8% versus 38.2%, P < 0.001), never-smokers (47.3% versus 43.8%, P = 0.015), and adenocarcinoma (70.4% versus 58.1%, P < 0.001) were more frequent in the younger group. While the EGFR mutation rate was lower in the younger group (52.5% versus 60.6%, P = 0.001), the primary site of lung cancer and stage distribution were not significantly different. If only adenocarcinoma patients were included in the analysis, female gender, older age, and never-smokers were more likely to have EGFR mutation. In conclusion, lung cancer in young patients (≦ 45 year-old) was associated with unique characteristics, with greater percentages of female patients, adenocarcinoma, and never-smokers and a lower EGFR mutation rate compared with older patients.


Assuntos
Receptores ErbB/genética , Neoplasias Pulmonares/etiologia , Mutação , Sistema de Registros , Fumar/efeitos adversos , Adulto , Fatores Etários , Quinase do Linfoma Anaplásico , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Receptores Proteína Tirosina Quinases/genética , Taiwan/epidemiologia
8.
J Invest Dermatol ; 135(5): 1329-1337, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25615554

RESUMO

In a routine phenotype-driven screen, we identified a point mutation in exon 7 of the IL-15 gene in Pedigree 191 (deficient memory (DM)) of N-ethyl-N-nitrosourea mutagenized mice. The DM epidermis expressed an alternatively spliced IL-15 mRNA isoform, IL-15ΔE7, and a wild-type (WT) IL-15 isoform at comparable levels. Mechanical stimulation of DM skin or DM skin graft transplanted onto the WT host resulted in reduced keratinocyte activation and inhibition of neutrophil infiltration into the dermis, demonstrating that DM keratinocytes produced less inflammatory response to external stimulation. Ectopic expression of IL-15ΔE7 in WT skin prevented abrasion-induced epidermal thickening, blocked the accumulation of nuclear antigen Ki67(+) cells in the basal and the suprabasal cell layers, increased loricrin expression, and also increased keratinocyte CXCL1 and G-CSF production. IL-15ΔE7 also profoundly blocked neutrophil infiltration in SDS- or immiquimod (IMQ)-treated WT skin. Recombinant IL-15ΔE7 failed to activate STAT-5 and its downstream target bcl-2 expression. Our study points to IL-15ΔE7 as a potential therapeutic agent for treating neutrophilia-associated inflammatory skin disorders.


Assuntos
Processamento Alternativo/fisiologia , Interleucina-15/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Psoríase/metabolismo , Psoríase/patologia , Estresse Mecânico , Processamento Alternativo/genética , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Quimiocina CXCL1/metabolismo , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos/metabolismo , Interleucina-15/genética , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/patologia , Mutação Puntual/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
9.
Hum Vaccin Immunother ; 8(9): 1243-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22894960

RESUMO

The efficacy and effectiveness of influenza vaccines depend primarily on the vaccine recipient and the virus similarity to the endemic virus. Regulatory T cells (Tregs) and cytokines are known to restrict immune responses against viral infections. We conducted this study to explore the role of Tregs, cytokines, and antibody production after influenza vaccination. The whole blood was collected from healthy subjects (n = 36) before and two weeks after influenza vaccine immunization for two or three consecutive years. The cell surface markers, intracellular staining of Foxp3(+) Tregs, and Th1/Th2 cytokines were determined. The antibody titer was detected using the hemagglutination inhibition test. The CD3(+), CD127(+), CD4(+)CD25(+) and CD4(+)Foxp3(+) cells were increased significantly post vaccination. The plasma level of the transforming growth factor (TGF-ß), but not interleukin (IL)-2, IL-4, IL-5, IL-10, IFN-γ, TNF-α, was also found to increase significantly after vaccination. We further correlated the cytokine fold-increases with the anti-influenza antibody titer for individual post vaccination. It was found that the IL-10 level after vaccination correlated with the fold-increases of anti-H1N1, anti-H3N2, anti-B/Yamagata, and anti-B/Victoria antibodies. But, a negative relationship occurs between the TGF-ß level and fold-increases of anti-H1N1, anti-H3N2, anti-B/Yamagata, and anti-B/Victoria antibodies post vaccination. Treg cells and TGF-ß seem to participate in the downregulation of the anti-influenza antibody response post influenza vaccination. Alteration of Treg activity might enhance influenza vaccine antibody responses and efficacy.


Assuntos
Anticorpos Antivirais/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Linfócitos T CD4-Positivos/enzimologia , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Influenza Humana/prevenção & controle , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
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