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1.
J Biomed Sci ; 31(1): 33, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38532423

RESUMO

BACKGROUND: T cell receptor (TCR) signaling and T cell activation are tightly regulated by gatekeepers to maintain immune tolerance and avoid autoimmunity. The TRAIL receptor (TRAIL-R) is a TNF-family death receptor that transduces apoptotic signals to induce cell death. Recent studies have indicated that TRAIL-R regulates T cell-mediated immune responses by directly inhibiting T cell activation without inducing apoptosis; however, the distinct signaling pathway that regulates T cell activation remains unclear. In this study, we screened for intracellular TRAIL-R-binding proteins within T cells to explore the novel signaling pathway transduced by TRAIL-R that directly inhibits T cell activation. METHODS: Whole-transcriptome RNA sequencing was used to identify gene expression signatures associated with TRAIL-R signaling during T cell activation. High-throughput screening with mass spectrometry was used to identify the novel TRAIL-R binding proteins within T cells. Co-immunoprecipitation, lipid raft isolation, and confocal microscopic analyses were conducted to verify the association between TRAIL-R and the identified binding proteins within T cells. RESULTS: TRAIL engagement downregulated gene signatures in TCR signaling pathways and profoundly suppressed phosphorylation of TCR proximal tyrosine kinases without inducing cell death. The tyrosine phosphatase SHP-1 was identified as the major TRAIL-R binding protein within T cells, using high throughput mass spectrometry-based proteomics analysis. Furthermore, Lck was co-immunoprecipitated with the TRAIL-R/SHP-1 complex in the activated T cells. TRAIL engagement profoundly inhibited phosphorylation of Lck (Y394) and suppressed the recruitment of Lck into lipid rafts in the activated T cells, leading to the interruption of proximal TCR signaling and subsequent T cell activation. CONCLUSIONS: TRAIL-R associates with phosphatase SHP-1 and transduces a unique and distinct immune gatekeeper signal to repress TCR signaling and T cell activation via inactivating Lck. Thus, our results define TRAIL-R as a new class of immune checkpoint receptors for restraining T cell activation, and TRAIL-R/SHP-1 axis can serve as a potential therapeutic target for immune-mediated diseases.


Assuntos
Receptores de Antígenos de Linfócitos T , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Humanos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Células Jurkat , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Transdução de Sinais , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/metabolismo , Fosforilação , Ativação Linfocitária , Tirosina/metabolismo
2.
Transplantation ; 107(7): 1492-1501, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36380450

RESUMO

BACKGROUND: Liver transplantation (LT) is the treatment of choice for patients with hepatocellular carcinoma (HCC). Recurrence of HCC after LT occurs in 10% to 20% of cases. Preclinical studies to evaluate immune checkpoint inhibitors in conjunction with immunosuppressant treatment in transplant recipients have been lacking. Here, we evaluated the efficacy, safety, and mechanism of programmed cell death-1 (PD1) blockade under tacrolimus treatment in transplant recipients. METHODS: We used a murine allogeneic skin transplantation model and murine syngeneic subcutaneous and orthotopic HCC models and measured the tumor volume and the change in tumor-infiltrating lymphocytes under PD1 blockade and tacrolimus treatment. RESULTS: Tacrolimus treatment prolonged allograft survival in the allogeneic transplantation model and enhanced tumor growth in both subcutaneous and orthotopic HCC models. PD1 blockade suppressed tumor growth and lung metastasis in correlation with the number of infiltrating CD8 + T cells. Under tacrolimus treatment, PD1 blockade still resulted in an antitumor effect accompanied by a significant increase in tumor-infiltrating CD8 + T cells, natural killer cells, dendritic cells, and natural killer T cells. Tacrolimus treatment rescued the acceleration of transplant rejection induced by PD1 blockade in the allogeneic transplantation model. CONCLUSIONS: Our data suggest that treatment with high-dose tacrolimus in conjunction with PD1 blockade has an antitumor effect and reduces transplant rejection in mouse models of allograft skin transplantation and HCC. Thus, these results suggest that a clinical trial of PD1 inhibitors for HCC in LT merits consideration.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Carcinoma Hepatocelular/patologia , Tacrolimo/farmacologia , Neoplasias Hepáticas/patologia , Imunoterapia , Imunossupressores/farmacologia , Linfócitos T CD8-Positivos
3.
J Immunol ; 208(7): 1534-1544, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35264458

RESUMO

Recent evidence from several autoimmune animal models has demonstrated that TRAIL suppresses the activation of T cells and inhibits autoimmune inflammation via an apoptosis-independent pathway. However, it remains unclear whether the immunosuppressive effects of TRAIL are dependent on its direct effects on T cells or on other immune cells to regulate T cells for the induction of disease. Therefore, we generated mice with T cell-specific TRAIL receptor (TRAIL-R) conditional knockout to investigate the impact of TRAIL on autoimmune inflammation and disease induction in experimental autoimmune encephalomyelitis (EAE). T cell-specific TRAIL-R knockout mice were found to completely reverse the TRAIL-mediated suppression of inflammation and disease induction, indicating that TRAIL-R on T cells is essential for TRAIL-mediated suppression of inflammation and disease induction in EAE. Moreover, the immune suppression effects were not due to the induction of cell apoptosis, but to the direct inhibition of T cell activation. In addition, RNA sequencing and transcriptome analysis revealed that TRAIL-R signaling significantly downregulated the genes involved in TCR signaling pathways, T cell differentiation, and proinflammatory cytokines. These results indicate that TRAIL-R on T cells is critical for pathologic T cell activation and induction of inflammation in EAE, suggesting that TRAIL-R serves as a novel immune checkpoint receptor in T cell-mediated autoimmune diseases.


Assuntos
Encefalomielite Autoimune Experimental , Animais , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T , Ligante Indutor de Apoptose Relacionado a TNF
4.
Lupus ; 30(11): 1849-1855, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34325541

RESUMO

Progressive multifocal leukoencephalopathy (PML) is one of the rare but lethal infectious complication in patients with SLE, manifesting progressive central nervous demyelination caused by JC virus (JCV). There have been no effective antiviral agents so far; however, immune checkpoint inhibitors (ICI) have been demonstrated as potential treatments by reinvigorating antiviral T-cell activity against JC virus. To date, sixteen PML cases treated with anti-PD-1 have been reported; however, there was no report addressing the use of ICI in patients with concomitant PML and rheumatic disease, possibly due to the concern for possible autoimmune disease flare-up. In addition, treatment outcomes of these ICI-treated cases were heterogeneous. Experiences from these cases suggested that high disease burden, JC viral load in CSF, and severe immunosuppression status at baseline may predict poor response to treatment. Our case, a 62-year-old woman with long-standing SLE, turned out to have a delayed but effective response to prolonged ICI treatment despite of her high JC viral load and immunosuppressed status caused by high-dose steroid and rituximab. To our knowledge, this is the first case report with SLE complicated with PML clinically improved by pembrolizumab treatment without consequent immune related adverse events (irAE). Considering the lethal nature of PML and absence of effective medication, ICI is a reasonable consideration in patients with SLE and progressive PML.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Leucoencefalopatia Multifocal Progressiva , Lúpus Eritematoso Sistêmico , Feminino , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Vírus JC , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/etiologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Pessoa de Meia-Idade
5.
Cancers (Basel) ; 13(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801815

RESUMO

Immune checkpoints play critical roles in the regulation of T-cell effector function, and the effectiveness of their inhibitors in cancer therapy has been established. Immune checkpoint inhibitors (ICIs) constitute a paradigm shift in cancer therapy in general and cancer immunotherapy in particular. Immunotherapy has been indicated to reinvigorate antitumor T-cell activity and dynamically modulate anticancer immune responses. However, despite the promising results in the use of immunotherapy in some cancers, numerous patients do not respond to ICIs without the existence of a clear predictive biomarker. Overall, immunotherapy involves a certain degree of uncertainty and complexity. Research on the exploration of cellular and molecular factors within the tumor microenvironment (TME) aims to identify possible mechanisms of immunotherapy resistance, as well as to develop novel combination strategies involving the specific targeting of the TME for cancer immunotherapy. The combination of this approach with other types of treatment, including immune checkpoint blockade therapy involving multiple agents, most of the responses and effects in cancer therapy could be significantly enhanced, but the appropriate combinations have yet to be established. Moreover, the in-depth exploration of complexity within the TME allows for the exploration of pathways of immune dysfunction. It may also aid in the identification of new therapeutic targets. This paper reviews recent advances in the improvement of therapeutic efficacy on the immune context of the TME and highlights its contribution to cancer immunotherapy.

6.
Cell Mol Immunol ; 18(7): 1772-1782, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32111985

RESUMO

Persistent hepatitis B virus (HBV) infection results in chronic liver diseases that may progress to chronic hepatitis, liver cirrhosis, and subsequent hepatocellular carcinoma. Previous studies demonstrated that adaptive immunity, in particular CD8 T cells, is critical in HBV elimination. Recent studies have revealed a distinct tissue-localized T cell lineage, tissue-resident memory (TRM) cells, that is crucial for protective immunity in peripheral tissues. In this study, we showed that treatment with an anti-asialo GM1 (ASGM1) antibody (Ab), which depletes NK cells, led to impairment of HBV clearance in a mouse animal model. Unexpectedly, the ability to clear HBV was not significantly impaired in NFIL3 KO mice, which are deficient in NK cells, implying that other non-NK ASGM1-positive immune cells mediate HBV clearance. We isolated intrahepatic ASGM1-positive cells from NFIL3 KO mice and analyzed the immune phenotype of these cells. Our results demonstrated a distinct population of CD44+ LFA-1hi CD8 T cells that were the major intrahepatic ASGM1-positive immune cells in NFIL3 KO mice. Importantly, transcriptome analysis revealed that these ASGM1-positive CD8 T cells had distinct gene profiles and shared a similar core gene signature with TRM cells. In addition to both transcriptional and phenotypic liver residency characteristics, ASGM1-positive CD8 T cells were able to home to and be retained in the liver after adoptive transfer. Taken together, our study results indicate that these ASGM1-positive liver-resident CD8 T cells are the major effector immune cells mediating anti-HBV immunity.


Assuntos
Hepatite B Crônica , Hepatite B , Animais , Linfócitos T CD8-Positivos , Gangliosídeo G(M1) , Vírus da Hepatite B , Fígado , Antígeno-1 Associado à Função Linfocitária , Camundongos , Camundongos Endogâmicos C57BL
7.
Arch Rheumatol ; 35(2): 170-179, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32851365

RESUMO

OBJECTIVES: This study aims to evaluate the efficacy and safety profile of opinercept for rheumatoid arthritis (RA) patients undergoing disease- modifying anti-rheumatic drugs (DMARDs) therapy. PATIENTS AND METHODS: A total of 98 patients with active RA (17 males, 81 females; mean age 58.6±12.2 years; range, 24.3 to 85.3 years) were randomized into opinercept plus DMARDs (OD group) or placebo plus DMARDs (PD group), in a 24-week treatment period. Primary outcome was American College of Rheumatology score (ACR20) at week 24. Other exploratory endpoints included ACR50, ACR70 and disease activity score-28 (DAS28) at week 12 and 24, tender/swollen joint counts, pain, Health Assessment Questionnaire-Disability Index, erythrocyte sedimentation rate, and C-reactive protein level. Incidence of adverse events (AEs), vital signs and physical findings, and laboratory test results were also evaluated. RESULTS: Patients in OD group showed significantly higher achievement percentage of ACR20 at week 24 than the PD group (76.6% vs. 30.3%, p<0.001). The evaluation of DAS28 was significantly improved in OD patients compared to PD patients at weeks 12 and 24. Most of the occurred AEs were mild or moderate and considered unrelated to study treatments. CONCLUSION: Opinercept concurrent with DMARDs was superior to DMARDs alone in slowing RA progression and ameliorating symptoms, with well- tolerated and acceptable safety profile.

8.
Rheumatology (Oxford) ; 59(11): 3340-3349, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32306043

RESUMO

OBJECTIVES: SLE is an autoimmune disease characterized by aberrant autoantibody production and immune dysfunctions. Whether the anti-CMV immunity is impaired in SLE patients is poorly understood. We investigated the specific anti-viral T-cell response in SLE patients with CMV infection and its possible impacts on clinical manifestations in lupus. METHODS: CD28 null T-cell percentages were measured by flow cytometry in 89 SLE patients and 58 healthy controls. A specific anti-CMV CD8 T-cell response was assessed ex vivo by the production of intracellular cytokines in response to CMV phosphoprotein 65 (pp65) by flow cytometry. Clinical manifestations and immune parameters were analysed in SLE patients according to their CMV serostatus. RESULTS: CD28 null T cells were significantly expanded in SLE patients. When the anti-CMV pp65 CD8 polyfunctional T cell response was analysed, as defined by production of at least three of four functional cytokines or effectors (intracellular IFN-γ, IL-2, TNF-α and surface CD107a), the results demonstrated that it was not impaired in SLE patients. In contrast, when comparing clinical manifestations, there were lower anti-ds-DNA levels and decreased SLEDAI in SLE patients with CMV infection. Furthermore, the expansion of CD4+CD28 null T cells was negatively associated with anti-ds-DNA levels and SLEDAI in these lupus patients. CONCLUSION: In SLE patients with CMV infection, the specific anti-CMV CD8 T-cell response is preserved but is associated with decreased disease activity and lower anti-DNA levels among these patients, suggesting CMV infection may mitigate lupus activity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Proteínas da Matriz Viral/imunologia , Adulto , Anticorpos Antivirais/sangue , Especificidade de Anticorpos , Antígenos CD28/imunologia , Linfócitos T CD4-Positivos/imunologia , Estudos de Casos e Controles , Citomegalovirus/imunologia , Infecções por Citomegalovirus/sangue , DNA/imunologia , Feminino , Citometria de Fluxo , Humanos , Imunidade Celular , Imunoglobulina G/sangue , Interferon gama/biossíntese , Interleucina-2/biossíntese , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/complicações , Ativação Linfocitária , Linfócitos Nulos/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/biossíntese , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/biossíntese
10.
Liver Cancer ; 8(3): 155-171, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31192153

RESUMO

BACKGROUND: Anti-programmed cell death-1(anti-PD1) treatment has shown promising antitumor efficacy in patients with advanced hepatocellular carcinoma (HCC). This study sought to explore the functional significance of programmed death ligand-1 (PD-L1) expression in tumor cells in the tumor microenvironment. METHODS: The mouse liver cancer cell line BNL-MEA was transfected with PD-L1 plasmids and stable clones expressing PD-L1 were selected. An orthotopic HCC model was generated by implanting the cells into the subcapsular space of BALB/c mice. Cell growth features were measured by proliferation assay, colony formation, flow cytometry (in vitro), ultrasonography, and animal survival (in vivo). The changes in T-cell function were examined by cytokine assay, expression of T-cell related genes, and flow cytometry. The efficacy of anti-PD1 therapy was compared between the parental and PD-L1-expressing tumors. RESULTS: PD-L1 expression did not affect growth characteristics of BNL-MEA cells but downregulated the expression of genes related to T-cell activation in the tumor microenvironment. Co-culture of PD-L1-expressing BNL-MEA cells with CD8+ T cells reduced T-cell proliferation and expression of cytokines IFNγ and TNFα. Tumors with PD-L1 expression showed better response to anti-PD1 therapy and depletion of CD8+ T cells abolished the antitumor effect. The difference in treatment response between parental and PD-L1-expressing tumors disappeared when a combination of anti-PD1 and sorafenib was given. CONCLUSIONS: PD-L1 expression in HCC cells may inhibit T-cell function in the liver tumor microenvironment. Anti-PD1 therapy appeared more effective in PD-L1-expressing than nonexpressing tumors, but the difference was diminished by the addition of sorafenib.

11.
Cancers (Basel) ; 11(4)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999581

RESUMO

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is the most common subtype of gastric lymphoma. Most gastric MALT lymphomas are characterized by their association with the Helicobacter pylori (HP) infection and are cured by first-line HP eradication therapy (HPE). Several studies have been conducted to investigate why most gastric MALT lymphomas remain localized, are dependent on HP infection, and show HP-specific intratumoral T-cells (e.g., CD40-mediated signaling, T-helper-2 (Th2)-type cytokines, chemokines, costimulatory molecules, and FOXP3+ regulatory T-cells) and their communication with B-cells. Furthermore, the reason why the antigen stimuli of these intratumoral T-cells with tonic B-cell receptor signaling promote lymphomagenesis of gastric MALT lymphoma has also been investigated. In addition to the aforementioned mechanisms, it has been demonstrated that the translocated HP cytotoxin-associated gene A (CagA) can promote B-cell proliferation through the activation of Src homology-2 domain-containing phosphatase (SHP-2) phosphorylation-dependent signaling, extracellular-signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), B-cell lymphoma (Bcl)-2, and Bcl-xL. Furthermore, the expression of CagA and these CagA-signaling molecules is closely associated with the HP-dependence of gastric MALT lymphomas (completely respond to first-line HPE). In this article, we summarize evidence of the classical theory of HP-reactive T-cells and the new paradigm of direct interaction between HP and B-cells that contributes to the HP-dependent lymphomagenesis of gastric MALT lymphomas. Although the role of first-line HPE in the treatment of HP-negative gastric MALT lymphoma remains uncertain, several case series suggest that a proportion of HP-negative gastric MALT lymphomas remains antibiotic-responsive and is cured by HPE. Considering the complicated interaction between microbiomes and the genome/epigenome, further studies on the precise mechanisms of HP- and other bacteria-directed lymphomagenesis in antibiotic-responsive gastric MALT lymphomas are warranted.

12.
J Med Econ ; 22(8): 777-787, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30982378

RESUMO

Aims: Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). This analysis investigated the cost-effectiveness of the second-line treatment with tofacitinib, compared with adalimumab, both plus methotrexate (MTX), in patients with moderate-to-severe RA and an inadequate response to the first-line MTX, from a Taiwan National Health Insurance Administration perspective. Materials and methods: A patient-level simulation model was used to project lifetime costs and quality-adjusted life-years (QALYs). Base-case analysis compared second-line treatment with tofacitinib 5 mg twice daily plus MTX vs adalimumab 40 mg every 2 weeks plus MTX. Patients switched or discontinued treatment due to a lack or loss of effectiveness or a serious adverse event. Efficacy was measured by change in Health Assessment Questionnaire-Disability Index (HAQ-DI) score. HAQ-DI scores were used to predict mortality and resource utilization, and were mapped onto utility values to estimate QALYs. Efficacy and safety data were derived from clinical trials and other secondary sources. Uncertainty in model parameters was explored using one-way deterministic and probabilistic sensitivity analyses. Results: Patients gained 0.09 more QALYs with second-line tofacitinib plus MTX compared with adalimumab plus MTX (5.13 vs 5.04, respectively) at an additional cost of New Taiwan Dollars (NT$) 12,881. The incremental cost-effectiveness ratio was NT$143,122/QALY. One-way sensitivity analysis confirmed the base-case result was robust. Limitations: The lack of available clinical data, particularly for HAQ-DI scores, may introduce some bias in the analysis. No patients were in an early stage of RA, which may limit the generalizability of these results. Base-case results from our study are not necessarily generalizable to countries with healthcare systems that differ considerably from Taiwan. Conclusions: From a payer perspective, second-line treatment with tofacitinib plus MTX is a cost-effective treatment strategy, compared with adalimumab plus MTX, in patients with moderate-to-severe RA in Taiwan.


Assuntos
Adalimumab/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Adalimumab/administração & dosagem , Adalimumab/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antirreumáticos/administração & dosagem , Antirreumáticos/economia , Análise Custo-Benefício , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Modelos Econômicos , Piperidinas/administração & dosagem , Piperidinas/economia , Pirimidinas/administração & dosagem , Pirimidinas/economia , Pirróis/administração & dosagem , Pirróis/economia , Anos de Vida Ajustados por Qualidade de Vida , Índice de Gravidade de Doença , Taiwan , Adulto Jovem
13.
Cell Death Dis ; 10(2): 77, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30692521

RESUMO

Human osteoclast formation from mononuclear phagocyte precursors involves interactions between members of the tumor necrosis factor (TNF) ligand superfamily and their receptors. Recent evidence indicated that TNF-α-related apoptosis-inducing ligand (TRAIL) induces osteoclast differentiation via a TRAF6-dependent signaling pathway; but paradoxically, it inhibits RANK ligand (RANKL)-induced osteoclast differentiation. Although a number of signaling pathways were linked to the RANK and osteoclastogenesis, it is not known how TRAIL regulates RANK signaling. In this study, we demonstrate that TRAIL regulates RANK-induced osteoclastogenesis in terms of the assembly of lipid raft-associated signaling complexes. RANKL stimulation induced recruitment of TRAF6, c-Src, and DAP-12 into lipid rafts. However, the RANKL-induced assembly of lipid raft-associated signaling complexes and TRAF6 recruitment was abolished in the presence of TRAIL. TRAIL-induced dissociation of RANKL-induced lipid raft signaling complexes was reversed by treatment with TRAIL receptor (TRAIL-R) siRNA or an anti-TRAIL-R blocking antibody, indicating that TRAIL mediates suppression of RANKL-induced lipid raft signaling via interactions with TRAIL-R. Finally, we demonstrated that TRAIL suppressed inflammation-induced bone resorption and osteoclastogenesis in a collagen-induced arthritis (CIA) rat animal model. Our results provide a novel apoptosis-independent role of TRAIL in regulating RANK signaling and suppresses osteoclast activation via inhibiting lipid raft assembly and TRAF6 recruitment.


Assuntos
Osteoclastos/metabolismo , Fragmentos de Peptídeos/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Fator 6 Associado a Receptor de TNF/genética , Animais , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Transfecção
14.
Front Immunol ; 9: 15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29403497

RESUMO

Objective: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces cell apoptosis by transducing apoptosis signals after interacting with its receptor (TRAIL-R). Although the actual biological role of TRAIL remains to be elucidated, recent accumulating evidence implies that TRAIL regulates immune responses and immune cell homeostasis via an apoptosis-independent pathway, suggesting a novel immune-regulatory role of TRAIL in autoimmune diseases. The purpose of this study is to address the immune-regulatory role and molecular mechanism of TRAIL in regulating T cell activation in autoimmune diseases. Design: TRAIL was administered to mice to induce experimental autoimmune encephalomyelitis (EAE), and to evaluate its impact on neuroinflammation and disease activity. The effects of TRAIL on neuroantigen [myelin oligodendrocyte glycoprotein (MOG)35-55]-activated T cell proliferation and cytokine production were investigated. TRAIL-treated MOG35-55-activated splenic Th17 cells were further adoptively transferred into Rag1 KO mice to induce passive EAE. Gene expression profiles of CD4+ T cells from EAE mice treated with TRAIL were analyzed by RNA sequencing and transcriptome analysis. Results: TRAIL suppressed autoimmune encephalomyelitis and inhibited T cell reactivity to neuro-antigen in murine EAE, and the effects were dependent on TRAIL-R signaling. Moreover, TRAIL directly inhibited activation of MOG35-55-activated CD4+ T cells, resulting in suppression of neuroinflammation and reduced disease activity in adoptive transfer-induced EAE. Furthermore, TRAIL-R signaling inhibited phosphorylation of proximal T cell receptor (TCR)-associated tyrosine kinases in activated CD4+ T cells. Importantly, TRAIL/TRAIL-R interaction downregulated TCR downstream signaling genes in RNA sequencing and transcriptome analysis. Conclusion: TRAIL/TRAIL-R interaction regulates CD4+ T cell activation in autoimmune inflammation and directly suppresses T cell activation via inhibiting TCR signaling, suggesting that TRAIL-R serves as a novel immune checkpoint in T cell responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Encefalomielite Autoimune Experimental/terapia , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T/antagonistas & inibidores , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transferência Adotiva , Animais , Apoptose/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/transplante , Proliferação de Células , Citocinas/biossíntese , Encefalomielite Autoimune Experimental/imunologia , Feminino , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/genética , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Glicoproteína Mielina-Oligodendrócito/metabolismo , Fragmentos de Peptídeos/metabolismo , Transdução de Sinais/imunologia
15.
Cell Death Dis ; 9(2): 135, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29374180

RESUMO

The ubiquitin E3 ligase DELTEX1 (DTX1) is specifically downregulated in gastric cancer tissues, and expression of DTX1 is linked to better prognoses and survival in gastric cancer. Cellular FLICE inhibitory protein (c-FLIP) is known for its pivotal role in the resistance of cancer cells to death receptor-induced cell death. Here, we show that DTX1 is an E3 ligase for c-FLIP in gastric cancer cells. DTX1 promoted c-FLIP downregulation. Overexpression of DTX1 sensitized gastric cancer cells to TRAIL-induced apoptosis, whereas DTX1-knockdown attenuated apoptosis induction. DTX1 binds c-FLIPL and directs it into the endosome-lysosomal pathway for proteasome-independent degradation. Moreover, induction of DTX1 in AGS cells by geldanamycin conferred susceptibility of those cells to TRAIL-induced apoptosis. Our results reveal a tumor-suppressive role for DTX1 and suggest a new approach to increasing TRAIL efficacy by raising DTX1 levels in gastric cancer therapy. DTX1 also enhanced c-FLIP degradation and FasL-induced and TRAIL-induced apoptosis in T cells, suggesting that DTX1 constitutes one of the physiological mechanisms regulating c-FLIP stability.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Neoplasias Gástricas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Linhagem Celular Tumoral , Progressão da Doença , Intervalo Livre de Doença , Regulação para Baixo/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Proteína Ligante Fas/metabolismo , Humanos , Lactamas Macrocíclicas/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Neoplasias Gástricas/patologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
17.
J Formos Med Assoc ; 117(11): 1003-1010, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29174174

RESUMO

BACKGROUND/PURPOSE: Chronic periodontitis (CP) and rheumatoid arthritis (RA) are the most common chronic inflammatory diseases and their immunopathogenesis is similar. The aim of this study was to evaluate the effect of non-surgical periodontal treatment on the serum levels of RA-related inflammatory markers in patients with chronic periodontitis. METHODS: Thirty-one Taiwanese adults with CP were included. Demographics and periodontal parameters, including probing depth, clinical attachment level, and number of remaining teeth in the oral cavity, were recorded. All subjects received non-surgical periodontal treatment such as scaling and subgingival root planing. Serum samples were collected before and after the treatment. Serum levels of anti-citrullinated protein antibodies (ACPA), rheumatoid factor, tumor necrosis factor-α (TNF-α), C-reactive protein, interleukin-1ß (IL-1ß), and Interleukin-6 (IL-6) were measured using an enzyme-linked immunosorbent assay. RESULTS: Non-surgical periodontal treatment significantly reduced the serum ACPA (p = 0.015) and TNF-α levels (p = 0.026) in CP patients, particularly in patients with generalized CP. Furthermore, there was a significant and positive correlation between the number of extracted teeth and the reduction in the serum ACPA (p = 0.05) and IL-1ß levels (p = 0.029) after non-surgical periodontal treatment. CONCLUSION: Non-surgical periodontal therapy may aid in the control of RA-related inflammatory markers in patients with CP. A large-scale study with well-defined populations is needed to clarify the benefit of non-surgical periodontal therapy.


Assuntos
Artrite Reumatoide/sangue , Biomarcadores/sangue , Periodontite Crônica/sangue , Periodontite Crônica/terapia , Raspagem Dentária , Curetagem Subgengival , Adulto , Anticorpos Antiproteína Citrulinada/sangue , Feminino , Humanos , Interleucina-1beta/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fator de Necrose Tumoral alfa/sangue
18.
J Rheumatol ; 45(1): 83-89, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29142034

RESUMO

OBJECTIVE: The aim of this population-based study is to examine the adverse events (AE) associated with longitudinal systemic glucocorticoid (GC) use among an ethnic Chinese systemic lupus erythematosus (SLE) cohort. METHODS: Our study subjects were patients with newly diagnosed SLE aged 18 and older who received at least 1 prescription of systemic GC between 2001 and 2012 from Taiwan's National Health Insurance Research Database (NHIRD). The earliest prescription date of systemic GC for each subject was defined as the index date. For each subject, we calculated the average prednisolone-equivalent dose and the medication possession ratio (MPR) of GC use every 90 days for each patient after the index date. Patients with a diagnosis of AE (defined by the International Classification of Diseases-9-Clinical Modification diagnosis code) during the followup were also identified from the NHIRD. Generalized estimating equations adjusted for propensity score were applied to examine the association between longitudinal GC use and risks of prespecified AE (musculoskeletal, gastrointestinal, ophthalmologic, infectious, cardiovascular, neuropsychiatric, metabolic, and dermatologic diseases). RESULTS: We identified 11,288 patients with SLE (mean followup: 6.28 yrs). Higher doses and higher MPR of GC were associated with increased risk of osteonecrosis [adjusted OR (aOR) 2.87-9.09]. Similar results were found regarding the risk of osteoporosis (aOR 1.71-3.67), bacterial infection (aOR 2.12-3.89), Cushingoid syndrome (aOR 6.51-62.03), and sleep disorder (aOR 1.42-3.59). CONCLUSION: To our knowledge, this is the first study to show that the dose and intensity of longitudinal use of GC were both associated with risk of AE among a nationwide Asian SLE cohort.


Assuntos
Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/etnologia , Adulto , Infecções Bacterianas/etnologia , Infecções Bacterianas/etiologia , Síndrome de Cushing/etnologia , Síndrome de Cushing/etiologia , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Programas Nacionais de Saúde , Osteonecrose/etnologia , Osteonecrose/etiologia , Osteoporose/etnologia , Osteoporose/etiologia , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/etnologia , Transtornos do Sono-Vigília/etiologia , Taiwan/etnologia , Resultado do Tratamento , Adulto Jovem
19.
Int J Rheum Dis ; 21(2): 362-372, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29205904

RESUMO

AIM: To review the published studies that dose down and then discontinue biologic therapy in patients with rheumatoid arthritis (RA), particularly concerning the criteria for such dosing and the impact on clinical outcomes. METHODS: Published studies conducted in patients with RA that sequentially decreased the dose and then discontinued therapy were included if one or more of the following biologic disease modifying antirheumatic drugs (bDMARDs) was evaluated: abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab, rituximab or tocilizumab. RESULTS: Five studies qualified for inclusion. The populations of patients with RA were heterogeneous among the studies; patients were required to have low disease activity (LDA) or to be in remission prior to dose titration. Approximately 25-65% of patients successfully decreased and in some cases, discontinued the bDMARD. However, the flare rate was higher than for the patients who remained on a standard dose. The only variable that predicted relapse in more than one study was down-titration of the bDMARD dose. CONCLUSION: In patients who have achieved LDA or remission, down-titration and discontinuation of bDMARD therapy may be attempted, with careful monitoring. However, it is likely that some patients will flare, and it is not known how to predict these patients.


Assuntos
Antirreumáticos/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/administração & dosagem , Antirreumáticos/efeitos adversos , Antirreumáticos/economia , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/economia , Artrite Reumatoide/imunologia , Produtos Biológicos/efeitos adversos , Produtos Biológicos/economia , Análise Custo-Benefício , Esquema de Medicação , Custos de Medicamentos , Humanos , Recidiva , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
20.
Cell Mol Immunol ; 15(9): 846-857, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28392572

RESUMO

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has been implicated in the regulation of inflammation in rheumatoid arthritis (RA), primarily due to its ability to promote apoptosis in synoviocytes and infiltrating lymphocytes. The aim of this study was to investigate the immunomodulatory mechanism and role of TRAIL in inflammatory arthritis. We created an animal model of inflammatory arthritis and demonstrated that TRAIL significantly inhibited joint inflammation and reduced the severity of arthritis. The suppression of joint inflammation was not due to the TRAIL-mediated induction of apoptosis in T cells, macrophages or synovial fibroblasts. In contrast, TRAIL directly inhibited T-cell proliferation and suppressed the production of cytokines, which indicated that TRAIL exerted its anti-inflammatory effects by direct inhibition of T-cell activation. Moreover, TRAIL receptor (TRAIL-R)-knockout mice developed more severe disease, and the protective effects of TRAIL were abolished in the experimental arthritis model in TRAIL-R knockout mice. From these results, we conclude that TRAIL suppresses joint inflammation via an apoptosis-independent pathway and directly inhibits T-cell activation. Our results provide a novel apoptosis-independent, immune regulatory role for TRAIL in suppressing inflammatory arthritis and shed light on the development of effective new therapies for autoimmune inflammatory diseases.


Assuntos
Artrite Experimental/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Animais , Apoptose/genética , Apoptose/imunologia , Artrite Experimental/genética , Artrite Experimental/patologia , Proliferação de Células/genética , Fibroblastos/imunologia , Fibroblastos/patologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Knockout , Ratos , Ratos Sprague-Dawley , Membrana Sinovial/imunologia , Membrana Sinovial/patologia , Linfócitos T/patologia , Ligante Indutor de Apoptose Relacionado a TNF/genética
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