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1.
Vaccines (Basel) ; 12(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38793728

RESUMO

Tuberculosis, caused by Mycobacterium tuberculosis (M. tuberculosis), remains a formidable global health challenge, affecting a substantial portion of the world's population. The current tuberculosis vaccine, bacille Calmette-Guérin (BCG), offers limited protection against pulmonary tuberculosis in adults, underscoring the critical need for innovative vaccination strategies. Cytokines are pivotal in modulating immune responses and have been explored as potential adjuvants to enhance vaccine efficacy. The strategic inclusion of cytokines as adjuvants in tuberculosis vaccines holds significant promise for augmenting vaccine-induced immune responses and strengthening protection against M. tuberculosis. This review delves into promising cytokines, such as Type I interferons (IFNs), Type II IFN, interleukins such as IL-2, IL-7, IL-15, IL-12, and IL-21, alongside the use of a granulocyte-macrophage colony-stimulating factor (GM-CSF) as an adjuvant, which has shown effectiveness in boosting immune responses and enhancing vaccine efficacy in tuberculosis models.

2.
Clin Cancer Res ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691100

RESUMO

PURPOSE: Radiation-mediated immune suppression limits efficacy and is a barrier in cancer therapy. Radiation induces negative regulators of tumor immunity including regulatory T cells (Treg). Mechanisms underlying Treg infiltration after radiotherapy (RT) are poorly defined. Given that dendritic cells (cDC) maintain Treg we sought to identify and target cDC signaling to block Treg infiltration after radiation. EXPERIMENTAL DESIGN: Transcriptomics and high dimensional flow cytometry revealed changes in murine tumor cDC that not only mediate Treg infiltration after RT, but associate with worse survival in human cancer datasets. Antibodies perturbing a cDC-CCL22-Treg axis were tested in syngeneic murine tumors. A prototype interferon-anti-epidermal growth factor receptor fusion protein (αEGFR-IFNα) was examined to block Treg infiltration and promote a CD8+ T cell response after RT. RESULTS: Radiation expands a population of mature cDC1 enriched in immunoregulatory markers that mediates Treg infiltration via the Treg-recruiting chemokine CCL22. Blocking CCL22 or Treg depletion both enhanced RT efficacy. αEGFR-IFNα blocked cDC1 CCL22 production while simultaneously inducing an antitumor CD8+ T cell response to enhance RT efficacy in multiple EGFR-expressing murine tumor models, including following systemic administration. CONCLUSIONS: We identify a previously unappreciated cDC mechanism mediating Treg tumor infiltration after RT. Our findings suggest blocking the cDC1-CCL22-Treg axis augments RT efficacy. αEGFR-IFNα added to RT provided robust antitumor responses better than systemic free interferon administration, and may overcome clinical limitations to interferon therapy. Our findings highlight the complex behavior of cDC after RT and provide novel therapeutic strategies for overcoming RT-driven immunosuppression to improve RT efficacy.

3.
Biomater Adv ; 159: 213835, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38531259

RESUMO

Additive manufacturing (AM) technology has paved the way for manufacturing personalised stents. However, there is a notable gap in comprehensive microstructure analyses and in vitro evaluations of the AM CoCr stents using advanced methodologies. To address this gap, this study focuses on investigating the microstructure and in vitro performance of personalised CoCr stents manufactured through micro-laser powder bed fusion (µ-LPBF). The evaluation process begins with the measurements of dimensions and surface roughness, followed by in-depth microstructural analyses. To improve surface roughness and reduce excessive strut size, the µ-LPBF stents undergo electrochemical polishing. Importantly, in vitro stent deployments are carried out in artificial arteries manufactured based on actual patients' data. Compared to the commercial MULTI-LINK VISION CoCr stent, the µ-LPBF personalised stents have rough surface finish (average roughness: 1.55 µm for µ-LPBF vs. 1.09 µm for commercial) and compromised grain microstructures (elongated for µ-LPBF vs. equiaxed for commercial). However, the personalised stents demonstrate better performances in in vitro tests. Notably, compared to the commercial stent in the two studied cases, they deliver larger lumen gains (up to 11.24 %) and reduced recoils (up to 4 times). This study validates the merit of the lesion-specific designs and the feasibility of using AM technology for stent fabrication.


Assuntos
Artérias , Stents , Humanos , Leitos , Comércio , Grão Comestível
4.
J Colloid Interface Sci ; 640: 750-760, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36898181

RESUMO

HYPOTHESIS: Despite that the development of Cu2SnS3 (CTS) catalyst has attracted increasing interests, few study has reported to investigate its heterogeneous catalytic degradation of organic pollutants in a Fenton-like process. Furthermore, the influence of Sn components towards Cu (II)/Cu (I) redox cycling in CTS catalytic systems remains a fascinating research. EXPERIMENTS: In this work, a series of CTS catalysts with controlled crystalline phases were prepared via a microwave-assisted pathway and applied in the H2O2 activation for phenol degradation. The efficiency of phenol degradation in CTS-1/H2O2 system (CTS-1: the molar ratio of Sn (copper acetate) and Cu (tin dichloride) is determined to be Sn:Cu = 1:1) was systematically investigated by controlling various reaction parameters including H2O2 dosage, initial pH and reaction temperature. We discovered that Cu2SnS3 exhibited superior catalytic activity to the contrast monometallic Cu or Sn sulfides and Cu (I) acted as the dominant active sites. The higher Cu (I) proportions conduce to the higher catalytic activities of CTS catalysts. Quenching experiments and electron paramagnetic resonance (EPR) further proved that the activation of H2O2 by CTS catalyst produces reactive oxygen species (ROS) and subsequently leads to degradation of the contaminants. A reasonable mechanism of enhanced H2O2 activation in Fenton-like reaction of CTS/H2O2 system was proposed for phenol degradation by investigating the roles of copper, tin and sulfur species. FINDINGS: The developed CTS acted as a promising catalyst in Fenton-like oxidation progress for phenol degradation. Importantly, the copper and tin species contribute to a synergetic effect for the promotion of Cu (II)/Cu (I) redox cycle, which thus enhanced the activation of H2O2. Our work may offer new insight on the facilitation of Cu (II)/Cu (I) redox cycle in Cu-based Fenton-like catalytic systems.

5.
Environ Pollut ; 316(Pt 1): 120460, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273687

RESUMO

Per- and polyfluorolkyl substances (PFAS) were measured in the water and fish from 20 coastal tourist resorts in China, to investigate their sources, seasonal differences, and bioconcentration. An oxidative method with hydroxyl radicals was used to extract potential perfluoroalkyl acid (PFAA) precursors in the water of resorts. The results indicated that the total concentrations of target chemicals (i.e., ΣPFAS) in the original water were 59.4-138, 32.7-77.2, and 14.6-29.9 ng L-1 in December, April, and August, respectively. C4-C10 perfluorocarboxlate (PFCA) and perfluorooctane sulfonate (PFOS) accounted for 67%-92% of the ΣPFAS contents in all water samples. The PFAS concentrations in the muscles and liver of fish were 16.0-162 ng g-1 ww and 186-1240 ng g-1 ww, respectively. The dominant compounds were perfluorobutanoate acid (PFBA) and PFOS in the water, and perfluorooctanoic acid (PFOA) and PFOS in fish tissues. High bioconcentration were observed for PFCA (C ≥ 8) and perfluorosulfonate (PFSA, C ≥ 6). After oxidative conversion, the water exhibited a noticeable increase in the ΣPFAS value. Precursors that generated C4-C9 PFCA were more prevalent than precursors that generated other PFCA upon oxidation. The concentration of C8-based precursor was higher than that of C6-based precursor in wet and dry seasons. This study is the first to apply an oxidative method to investigate PFAS pollution in the water of coastal tourist resorts. The results verified that PFAA precursors exist in the water of coastal tourist resorts, and more attention should be given to the existence of PFAA precursors and the safety of water in coastal tourist resorts.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Animais , Fluorocarbonos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Ácidos Carboxílicos/química , Ácidos Alcanossulfônicos/análise , Água , Peixes
6.
Cell Rep Med ; 3(3): 100554, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35492873

RESUMO

Mutations in STK11/LKB1 in non-small cell lung cancer (NSCLC) are associated with poor patient responses to immune checkpoint blockade (ICB), and introduction of a Stk11/Lkb1 (L) mutation into murine lung adenocarcinomas driven by mutant Kras and Trp53 loss (KP) resulted in an ICB refractory syngeneic KPL tumor. Mechanistically this occurred because KPL mutant NSCLCs lacked TCF1-expressing CD8 T cells, a phenotype recapitulated in human STK11/LKB1 mutant NSCLCs. Systemic inhibition of Axl results in increased type I interferon secretion from dendritic cells that expanded tumor-associated TCF1+PD-1+CD8 T cells, restoring therapeutic response to PD-1 ICB in KPL tumors. This was observed in syngeneic immunocompetent mouse models and in humanized mice bearing STK11/LKB1 mutant NSCLC human tumor xenografts. NSCLC-affected individuals with identified STK11/LKB1 mutations receiving bemcentinib and pembrolizumab demonstrated objective clinical response to combination therapy. We conclude that AXL is a critical targetable driver of immune suppression in STK11/LKB1 mutant NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Receptor de Morte Celular Programada 1/genética , Proteínas Serina-Treonina Quinases/genética , Receptor Tirosina Quinase Axl
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-935044

RESUMO

@#[摘 要] 新兴的肿瘤免疫疗法是通过激活抗原特异性T细胞来实现强大的抗肿瘤反应,尽管其取得了令人瞩目的进展,但许多肿瘤患者对这些抗肿瘤疗法仅部分出现反应或根本没有反应。mRNA-脂质纳米颗粒(mRNA-LNP)技术可以应用于肿瘤免疫治疗,目前正在多个领域进行研究,包括治疗性肿瘤疫苗、双特异性抗体、细胞因子、共刺激配体和受体以及CAR-T细胞治疗等,而其中研究比较集中的领域则是治疗性肿瘤疫苗和肿瘤内免疫治疗。治疗性肿瘤疫苗使用编码含有在肿瘤中发现的突变肽,即创建一种由患者肿瘤特有的由新抗原组成的个性化肿瘤疫苗。肿瘤内免疫治疗是通过提供编码有效免疫刺激蛋白的mRNA将免疫细胞浸润很少的“冷”肿瘤转化为免疫细胞浸润增加的“热”肿瘤,以在有限的全身毒性的情况下促进有效的抗肿瘤免疫活性。mRNA-LNP技术在肿瘤免疫疗法的多个领域的应用为肿瘤免疫治疗注入了新的活力。

9.
Nat Commun ; 12(1): 5866, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620867

RESUMO

Type I interferon is promising in treating different kinds of tumors, but has been limited by its toxicity, lack of tumor targeting, and very short half-life. To target tumors, reduce systemic toxicity, and increase half-life, here we engineer a masked type I IFN-Fc (ProIFN) with its natural receptor connected by a cleavable linker that can be targeted by tumor-associated proteases. ProIFN has a prolonged serum half-life and shows an improved tumor-targeting effect. Interestingly, ProIFN-treated mice show enhanced DC cross-priming and significant increased CD8+ infiltration and effector function in the tumor microenvironment. ProIFN is able to improve checkpoint blockade efficacy in established tumors, as well as radiation efficacy for both primary and metastatic tumors. ProIFN exhibits superior long-term pharmacokinetics with minimal toxicity in monkeys. Therefore, this study demonstrates an effective tumor-activating IFN that can increase targeted immunity against primary tumor or metastasis and reduce periphery toxicity to the host.


Assuntos
Antineoplásicos/imunologia , Imunidade , Interferon Tipo I/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Microscopia Crioeletrônica , Haplorrinos , Imunoterapia , Cinética , Camundongos , Microambiente Tumoral
10.
Nat Commun ; 12(1): 2768, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986267

RESUMO

As a potent lymphocyte activator, interleukin-2 (IL-2) is an FDA-approved treatment for multiple metastatic cancers. However, its clinical use is limited by short half-life, low potency, and severe in vivo toxicity. Current IL-2 engineering strategies exhibit evidence of peripheral cytotoxicity. Here, we address these issues by engineering an IL-2 prodrug (ProIL2). We mask the activity of a CD8 T cell-preferential IL-2 mutein/Fc fusion protein with IL2 receptor beta linked to a tumor-associated protease substrate. ProIL2 restores activity after cleavage by tumor-associated enzymes, and preferentially activates inside tumors, where it expands antigen-specific CD8 T cells. This significantly reduces IL-2 toxicity and mortality without compromising antitumor efficacy. ProIL2 also overcomes resistance of cancers to immune checkpoint blockade. Lastly, neoadjuvant ProIL2 treatment can eliminate metastatic cancer through an abscopal effect. Taken together, our approach presents an effective tumor targeting therapy with reduced toxicity.


Assuntos
Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Interleucina-2/farmacologia , Neoplasias/tratamento farmacológico , Pró-Fármacos/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia/métodos , Interleucina-2/efeitos adversos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfotoxina-alfa/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/farmacologia
11.
Sci Transl Med ; 13(582)2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627484

RESUMO

Tumor-induced CD45-Ter119+CD71+ erythroid progenitor cells, termed "Ter cells," promote tumor progression by secreting artemin (ARTN), a neurotrophic peptide that activates REarranged during Transfection (RET) signaling. We demonstrate that both local tumor ionizing radiation (IR) and anti-programmed death ligand 1 (PD-L1) treatment decreased tumor-induced Ter cell abundance in the mouse spleen and ARTN secretion outside the irradiation field in an interferon- and CD8+ T cell-dependent manner. Recombinant erythropoietin promoted resistance to radiotherapy or anti-PD-L1 therapies by restoring Ter cell numbers and serum ARTN concentration. Blockade of ARTN or potential ARTN signaling partners, or depletion of Ter cells augmented the antitumor effects of both IR and anti-PD-L1 therapies in mice. Analysis of samples from patients who received radioimmunotherapy demonstrated that IR-mediated reduction of Ter cells, ARTN, and GFRα3, an ARTN signaling partner, were each associated with tumor regression. Patients with melanoma who received immunotherapy exhibited favorable outcomes associated with decreased expression of GFRα3. These findings demonstrate an out-of-field, or "abscopal," effect mediated by adaptive immunity, which is induced during local tumor irradiation. This effect, in turn, governs the therapeutic effects of radiation and immunotherapy. Therefore, our results identify multiple targets to potentially improve outcomes after radiotherapy and immunotherapy.


Assuntos
Células Precursoras Eritroides , Neoplasias , Imunidade Adaptativa , Animais , Humanos , Imunoterapia , Camundongos , Proteínas do Tecido Nervoso
12.
Cancer Cell ; 39(1): 96-108.e6, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33338425

RESUMO

Increased neoantigens in hypermutated cancers with DNA mismatch repair deficiency (dMMR) are proposed as the major contributor to the high objective response rate in anti-PD-1 therapy. However, the mechanism of drug resistance is not fully understood. Using tumor models defective in the MMR gene Mlh1 (dMLH1), we show that dMLH1 tumor cells accumulate cytosolic DNA and produce IFN-ß in a cGAS-STING-dependent manner, which renders dMLH1 tumors slowly progressive and highly sensitive to checkpoint blockade. In neoantigen-fixed models, dMLH1 tumors potently induce T cell priming and lose resistance to checkpoint therapy independent of tumor mutational burden. Accordingly, loss of STING or cGAS in tumor cells decreases tumor infiltration of T cells and endows resistance to checkpoint blockade. Clinically, downregulation of cGAS/STING in human dMMR cancers correlates with poor prognosis. We conclude that DNA sensing within tumor cells is essential for dMMR-triggered anti-tumor immunity. This study provides new mechanisms and biomarkers for anti-dMMR-cancer immunotherapy.


Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Proteínas de Membrana/genética , Proteína 1 Homóloga a MutL/deficiência , Neoplasias/genética , Nucleotidiltransferases/genética , Animais , Linhagem Celular Tumoral , Reparo de Erro de Pareamento de DNA , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon beta/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Transplante de Neoplasias , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Nucleotidiltransferases/metabolismo , Prognóstico , Transdução de Sinais/efeitos dos fármacos
13.
Huan Jing Ke Xue ; 41(12): 5428-5437, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33374059

RESUMO

Coastal tourism resorts have been developing rapidly in recent years, and the quality of their waterbodies directly affects human health. Perfluoroalkyl substances (PFASs) are found in every environmental medium and have garnered widespread social concern because of their potential ecological harm. This study investigated the contamination characteristics and potential ecological risks of 12 PFASs in the water and sediment of 20 coastal tourism resorts in Shandong Peninsula. The results revealed that all targeted pollutants were observed in the water and most sediment samples collected from the coastal tourism resorts. The sum of the 12 PFASs ∑PFASs averaged 67.91 ng·L-1 and 5.89 ng·g-1 in the water and sediment, respectively. The predominant compounds were perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in both water and sediment. The ∑PFASs and its homologues concentration indicated the spatial variations in the water and sediment of different tourism resorts, and the values were higher in the tourism resorts near the city center and the industrial areas than in other areas. The partition coefficient (Kd) of all the target compounds in the water/sediment system of different tourism resorts showed obvious differences. In addition, the Kd of the compounds with longer carbon chains (C ≥ 7) generally had higher Kd values, which suggests that long-chain PFAAs are prone to adsorption by sediment. Therefore, the discharge of municipal industrial wastewater and domestic sewage is the main source of contamination. The salinity of water and the total carbon contents of sediment did not show any effect on the partition of PFASs in the water/sediment system. PFOS and PFOA might have great potential ecological risks in the water environment of all tourism resorts.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Caprilatos , China , Cidades , Monitoramento Ambiental , Fluorocarbonos/análise , Humanos , Turismo , Água , Poluentes Químicos da Água/análise
14.
Nat Immunol ; 21(11): 1470, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32939095

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
Nat Immunol ; 21(5): 546-554, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32231300

RESUMO

High-dose radiation activates caspases in tumor cells to produce abundant DNA fragments for DNA sensing in antigen-presenting cells, but the intrinsic DNA sensing in tumor cells after radiation is rather limited. Here we demonstrate that irradiated tumor cells hijack caspase 9 signaling to suppress intrinsic DNA sensing. Instead of apoptotic genomic DNA, tumor-derived mitochondrial DNA triggers intrinsic DNA sensing. Specifically, loss of mitochondrial DNA sensing in Casp9-/- tumors abolishes the enhanced therapeutic effect of radiation. We demonstrated that combining emricasan, a pan-caspase inhibitor, with radiation generates synergistic therapeutic effects. Moreover, loss of CASP9 signaling in tumor cells led to adaptive resistance by upregulating programmed death-ligand 1 (PD-L1) and resulted in tumor relapse. Additional anti-PD-L1 blockade can further overcome this acquired immune resistance. Therefore, combining radiation with a caspase inhibitor and anti-PD-L1 can effectively control tumors by sequentially blocking both intrinsic and extrinsic inhibitory signaling.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Caspase 9/metabolismo , Inibidores de Caspase/uso terapêutico , Quimiorradioterapia/métodos , Neoplasias Colorretais/terapia , Ácidos Pentanoicos/uso terapêutico , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Caspase 9/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante de Neoplasias , Transdução de Sinais , Regulação para Cima
16.
Mar Pollut Bull ; 136: 481-490, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30509833

RESUMO

Precursors that can be transformed into perfluoroalkyl acids (PFAAs) have not been investigated in detail. In this study, the levels of potential PFAA precursors in the Jiaozhou Bay, inflowing rivers, and STP (sewage treatment plant) effluents were investigated by converting all PFAA precursors into perfluorinated carboxylic acids (PFCAs) by chemical oxidation. The significance of controlling PFAA precursors was indicated by the ratios of PFCAs converted by the oxidative treatment of precursors to PFAAs before oxidation (∑△[PFCAC4-C12]/∑[PFAA]before oxidation). The higher levels of △[PFCAC4-C12] (average = 18.89 ng/L) and lower ratios (∑△[PFCAC4-C12]/∑[PFAA]before oxidation, average = 0.21) were revealed in the STP effluents rather than in the water of the Jiaozhou Bay and rivers, which implied the precursors conversion during the sewage treatment process. The concentrations of △[PFCAs] and the aforementioned ratios showed apparent spatial and temporal differences. These results indicated that STPs were the important sources of precursors to other water bodies.


Assuntos
Fluorocarbonos/análise , Fluorocarbonos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Baías , China , Monitoramento Ambiental/métodos , Radical Hidroxila , Oxirredução , Rios , Esgotos/química
17.
PLoS Pathog ; 14(11): e1007455, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30444918

RESUMO

[This corrects the article DOI: 10.1371/journal.ppat.1007075.].

18.
J Virol ; 92(21)2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30111563

RESUMO

Hepatitis C virus (HCV) infection is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV can be sensed by host innate immunity to induce expression of interferons (IFNs) and a number of antiviral effectors. In this study, we found HCV infection induced the expression of neuralized E3 ubiquitin protein ligase 3 (NEURL3), a putative E3 ligase, in a manner that requires the involvement of innate immune sensing but is independent of the IFN action. Furthermore, we showed that NEURL3 inhibited HCV infection while it had little effect on other RNA viruses, including Zika virus (ZIKV), dengue virus (DENV), and vesicular stomatitis virus (VSV). Mechanistic studies demonstrated that NEURL3 inhibited HCV assembly by directly binding HCV envelope glycoprotein E1 to interfere with the E1/E2 heterodimerization, an important prerequisite for virion morphogenesis. Finally, we showed that knockout of NEURL3 significantly enhanced HCV infection. In summary, we identified NEURL3 as a novel inducible antiviral host factor that suppresses HCV assembly. Our results not only shed new insight into how host innate immunity acts against HCV but also revealed a new important biological function for NEURL3.IMPORTANCE The exact biological function of NEURL3, a putative E3 ligase, remains largely unknown. In this study, we found that NEURL3 could be upregulated upon HCV infection in a manner dependent on pattern recognition receptor-mediated innate immune response. NEURL3 inhibits HCV assembly by directly binding viral E1 envelope glycoprotein to disrupt its interaction with E2, an action that requires its Neuralized homology repeat (NHR) domain but not the RING domain. Furthermore, we found that NEURL3 has a pangenotypic anti-HCV activity and interacts with E1 of genotypes 2a, 1b, 3a, and 6a but does not inhibit other closely related RNA viruses, such as ZIKV, DENV, and VSV. To our knowledge, our study is the first report to demonstrate that NEURL3 functions as an antiviral host factor. Our results not only shed new insight into how host innate immunity acts against HCV, but also revealed a new important biological function for NEURL3.


Assuntos
Antivirais/farmacologia , Hepatite C/prevenção & controle , Imunidade Inata/imunologia , Infecções por Vírus de RNA/virologia , Ubiquitina-Proteína Ligases/farmacologia , Proteínas do Envelope Viral/antagonistas & inibidores , Vírus da Dengue/efeitos dos fármacos , Células HEK293 , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Infecções por Vírus de RNA/tratamento farmacológico , Infecções por Vírus de RNA/imunologia , Vírus de RNA/imunologia , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismo , Montagem de Vírus , Zika virus/efeitos dos fármacos
19.
PLoS Pathog ; 14(5): e1007075, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29782532

RESUMO

Toll-like receptor 3 (TLR3) senses dsRNA intermediates produced during RNA virus replication to activate innate immune signaling pathways through adaptor protein TRIF. Many viruses have evolved strategies to block TLR3-mediated interferon signaling via targeting TRIF. Here we studied how hepatitis C virus (HCV) antagonizes the TLR3-mediated interferon signaling. We found that HCV-encoded NS4B protein inhibited TLR3-mediated interferon signaling by down-regulating TRIF protein level. Mechanism studies indicated that the downregulation of TRIF by NS4B was dependent on caspase8. NS4B transfection or HCV infection can activate caspase8 to promote TRIF degradation, leading to suppression of TLR3-mediated interferon signaling. Knockout of caspase8 can prevent TRIF degradation triggered by NS4B, thereby enhancing the TLR3-mediated interferon signaling activation in response to HCV infection. In conclusion, our work revealed a new mechanism for HCV to evade innate immune response by blocking the TLR3-mediated interferon signaling via NS4B-induced TRIF degradation.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Hepacivirus/fisiologia , Interferons/metabolismo , Transdução de Sinais/fisiologia , Receptor 3 Toll-Like/antagonistas & inibidores , Proteínas não Estruturais Virais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sistemas CRISPR-Cas , Caspase 8/genética , Caspase 8/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Evasão da Resposta Imune/fisiologia , Imunidade Inata/imunologia , Proteínas de Membrana/fisiologia , Receptor 3 Toll-Like/metabolismo , Transfecção
20.
Immunity ; 47(2): 363-373.e5, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28801234

RESUMO

Inhibition of cytosolic DNA sensing represents a strategy that tumor cells use for immune evasion, but the underlying mechanisms are unclear. Here we have shown that CD47-signal regulatory protein α (SIRPα) axis dictates the fate of ingested DNA in DCs for immune evasion. Although macrophages were more potent in uptaking tumor DNA, increase of DNA sensing by blocking the interaction of SIRPα with CD47 preferentially occurred in dendritic cells (DCs) but not in macrophages. Mechanistically, CD47 blockade enabled the activation of NADPH oxidase NOX2 in DCs, which in turn inhibited phagosomal acidification and reduced the degradation of tumor mitochondrial DNA (mtDNA) in DCs. mtDNA was recognized by cyclic-GMP-AMP synthase (cGAS) in the DC cytosol, contributing to type I interferon (IFN) production and antitumor adaptive immunity. Thus, our findings have demonstrated how tumor cells inhibit innate sensing in DCs and suggested that the CD47-SIRPα axis is critical for DC-driven antitumor immunity.


Assuntos
Antígenos de Diferenciação/metabolismo , Neoplasias do Colo/imunologia , DNA Mitocondrial/imunologia , Células Dendríticas/imunologia , Proteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo , Animais , Anticorpos Bloqueadores/uso terapêutico , Antígeno CD47/imunologia , Antígeno CD47/metabolismo , Células Cultivadas , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Apresentação Cruzada , Modelos Animais de Doenças , Humanos , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Evasão Tumoral
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