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Vibrio vulnificus (Vv) is known to cause life-threatening infections, particularly septicemia. These patients often exhibit elevated levels of pro-inflammatory cytokines. While it is established that mitogen-activated protein kinase (MAPK)-interacting kinase (MNK) contributes to the production of pro-inflammatory cytokines, the role of MNK in macrophages during Vv infection remains unclear. In this study, we investigate the impact of MNK on macrophages. We demonstrate that the inhibition of MNK in J774A.1 cells, when treated with lipopolysaccharide or Vv, resulted in decreased production of tumor necrosis factor alpha and interleukin-6, without affecting their transcription. Interestingly, treatment with MNK inhibitor CGP57380 led to enhanced phosphorylation of MNK1 but decreased phosphorylation of eIF4E. Moreover, MNK1 knockout cells exhibited an increased capacity for phagocytosis and clearance of Vv, with more acidic phagosomes than the parental cells. Notably, CGP57380 did not impact phagocytosis, bacterial clearance, or phagosome acidification in Vv-infected J774A.1 cells. Considering the reported association between MNK and mammalian target of rapamycin complex 1 (mTORC1) activation, we investigated the mTORC1 signaling in MNK1 knockout cells infected with Vv. Our results revealed that attenuation of the mTORC1 signaling in these cells and treatment with the mTORC1 inhibitor rapamycin significantly enhanced bacterial clearance in J774A.1 cells following Vv infection. In summary, our findings suggest that MNK promotes the Vv-induced cytokine production in J774A.1 cells without affecting their transcription levels. MNK1 appears to impair the phagocytosis, bacterial clearance, and phagosome acidification in Vv-infected J774A.1 cells through the MNK1-mTORC1 signaling pathway rather than the MNK1-eIF4E signaling pathway. Our findings highlight the importance of the MNK1-mTORC1 pathway in modulating macrophage responses to Vv infection. IMPORTANCE: Mitogen-activated protein kinase (MAPK)-interacting kinase (MNK) plays a role in promoting the production of tumor necrosis factor alpha and interleukin-6 in macrophages during Vibrio vulnificus (Vv) infection. Inhibition or knockout of MNK1 in J774A.1 cells resulted in reduced cytokine production without affecting their transcription levels. MNK1 also impairs phagocytosis, bacterial clearance, and phagosome acidification in Vv-infected cells through the MNK1-mammalian target of rapamycin complex 1 (mTORC1) signaling pathway. The findings highlight the importance of the MNK1-mTORC1 pathway in modulating macrophage responses to Vv infection.
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Macrófagos , Alvo Mecanístico do Complexo 1 de Rapamicina , Fagocitose , Proteínas Serina-Treonina Quinases , Vibrio vulnificus , Vibrio vulnificus/metabolismo , Vibrio vulnificus/genética , Macrófagos/microbiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Animais , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Linhagem Celular , Vibrioses/imunologia , Vibrioses/microbiologia , Transdução de Sinais , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fosforilação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Humanos , Compostos de Anilina , PurinasRESUMO
Genome editing has the potential to improve the unsatisfactory therapeutic effect of antitumor immunotherapy. However, the cell plasma membrane prevents the entry of almost all free genome-manipulation agents. Therefore, a system can be spatiotemporally controlled and can instantly open the cellular membrane to allow the entry of genome-editing agents into target cells is needed. Here, inspired by the ability of T cells to deliver cytotoxins to cancer cells by perforation, an ultrasound (US)-controlled perforation system (UPS) is established to enhance the delivery of free genome-manipulating agents. The UPS can perforate the tumor cell membrane while maintaining cell viability via a controllable lipid peroxidation reaction. In vitro, transmembrane-incapable plasmids can enter cells and perform genome editing with the assistance of UPS, achieving an efficiency of up to 90%. In vivo, the UPS is biodegradable, nonimmunogenic, and tumor-targeting, enabling the puncturing of tumor cells under US. With the application of UPS-assisted genome editing, gasdermin-E expression in 4T1 tumor-bearing mice is successfully restored, which leads to pyroptosis-mediated antitumor immunotherapy via low-dose X-ray irradiation. This study provides new insights for designing a sonoporation system for genome editing. Moreover, the results demonstrate that restoring gasdermin expression by genome editing significantly improves the efficacy of radioimmunotherapy.
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Piroptose , Radioimunoterapia , Linfócitos T , Animais , Camundongos , Linhagem Celular Tumoral , Humanos , Radioimunoterapia/métodos , Linfócitos T/metabolismo , Raios X , Edição de Genes , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Feminino , Ondas Ultrassônicas , GasderminasRESUMO
The Gasdermin protein is a membrane disruptor that can mediate immunogenic pyroptosis and elicit anti-tumor immune function. However, cancer cells downregulate Gasdermin and develop membrane repair mechanisms to resist pyroptosis. Therefore, an artificial membrane disruptor (AMD) that can directly mediate membrane rupture in pyroptosis-deficient cells and induce antitumor immune responses in a controllable manner will be valuable in preclinical and clinical research. A micron-scale Ce6-based AMD that can directly induce plasma membrane rupture (PMR) in gasdermin-deficient tumor cells is established. Micron-scale AMDs localize Ce6 specifically to the plasma membrane without labeling other organelles. Compared to free Ce6 molecules, the use of AMDs results in a higher degree of specificity for the plasma membrane. Due to this specificity, AMDs mediate fast and irreversible PMR under 660 nm red light. Furthermore, the AMDs are capable of inducing programmed cell death and lytic cell death in a catalytic manner, demonstrating that the amount of Ce6 used by AMDs is only one-fifth of that used by Ce6 alone when inducing 80% of cancer cell death. In vivo, the AMDs show specificity for tumor targeting and penetration, suggesting that light-driven programmed cell death is specific to tumors. AMDs are applied to antitumor therapy in gasdermin-deficient tumors, resulting in efficient tumor elimination with minimal damage to major organs when combined with anti-PD-1 therapy. Tumor regression is correlated with PMR-mediated inflammation and T-cell-based immune responses. This study provides new insights for designing bioinspired membrane disruptors for PMR and mediating anti-tumor immunotherapy. Additionally, AMD is a dependable tool for examining the immunogenicity of PMR both in vitro and in vivo.
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Membrana Celular , Animais , Camundongos , Membrana Celular/metabolismo , Humanos , Modelos Animais de Doenças , Linhagem Celular Tumoral , Neoplasias/imunologia , Piroptose/imunologia , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismoRESUMO
A Cytotoxic T lymphocyte-inspired system capable of using ultralow-dose chemical drugs to manipulate cell death is needed to investigate the antitumor immunotherapy. Recent studies reveal pyroptosis promotes antitumor immune function. However, high-dose chemotherapy leads to cytokine release syndrome by pyroptosis. Therefore, pyroptosis-inducing ultralow-dose chemotherapy is potential in preclinical and clinical research, but its efficacy, safety, and the antitumor immune responses are not clear. Here, a near-infrared light controllable killing system (BIK system) is established by which ultralow-dose doxorubicin can be spatiotemporally transported to tumor cells and mediate efficient pyroptosis. This BIK system reduces total drug consumption to less than one-thirtieth the common dose in vitro. Moreover, this BIK system exhibited good tumor targeting and tumor penetration. This system is applied for pyroptosis-induced antitumor therapies, which shows less than ≈25 µg kg-1 doxorubicin is sufficient for tumor regression with negligible injuries to major organs. The antitumor immune function are proven to correlate with the impressive efficacy of pyroptosis-inducing ultralow-dose chemotherapy. This study provides new insights into the design of nanoassisted systems for activating the antitumor immunity by microstimulation; the application of the BIK system suggests that ultralow-dose chemotherapy is sufficient for inducing a robust pyroptosis-mediated antitumor immunity.
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Neoplasias , Piroptose , Humanos , Linfócitos T Citotóxicos , Neoplasias/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , ImunidadeRESUMO
In 2019, a dengue outbreak occurred with 290 confirmed cases in Wenzhou, a coastal city in southeast China. To identify the origin of the dengue virus (DENV) from this outbreak, viral RNA was extracted from four serum samples and sequenced for whole genome analysis. Then, phylogenetic analysis, gene mutation, secondary structure prediction, selection pressure analysis, and recombination analysis were performed. DENV strains Cam-03 and Cam-11 were isolated from patients traveling from Cambodia, while ZJWZ-18 and ZJWZ-62 strains were isolated from local patients without a record of traveling abroad. The whole genome sequence of all four strains was 10,735 nucleotides long. Phylogenetic tree analysis showed that the four strains belonged to genotype 1 of DENV-1, but the local Wenzhou strains and imported strains clustered in different branches. ZJWZ-18 and ZJWZ-62 were closely related to strain MF033254-Singapore-2016, and Cam-03 and Cam-11 were closely related to strain AB608788-China : Taiwan-1994. A comparison of the coding regions between the local strains and the DENV-1 standard strain (EU848545-Hawaii-1944) showed 82 amino acid mutations between the two strains. A total of 55 amino acid mutations were found between the coding regions of the local and imported strains. The overall secondary structure of the 3' UTR of the local strains had changed: apparent changes in the head and tail position were observed when compared to DENV-1 standard strain. Furthermore, selection pressure analysis and recombination detection using the 4 isolates and 41 reference strains showed two credible positive selection sites and eight credible recombination events, which warrant further studies. This study may enhance the understanding of viral replication, infection, evolution, virulence, and pathogenicity of DENV.
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Vírus da Dengue , Dengue , Aminoácidos , China/epidemiologia , Dengue/epidemiologia , Surtos de Doenças , Genoma Viral , Genótipo , Humanos , FilogeniaRESUMO
Circular RNAs (circRNAs) are a novel type of non-coding RNAs that have aroused growing attention in this decade. They are widely expressed in eukaryotes and generally have high stability owing to their special closed-loop structure. Many circRNAs are abundant, evolutionarily conserved, and exhibit cell-type-specific and tissue-specific expression patterns. Mounting evidence suggests that circRNAs have regulatory potency for gene expression by acting as microRNA sponges, interacting with proteins, regulating transcription, or directly undergoing translation. Dysregulated expression of circRNAs were found in many pathological conditions and contribute to the pathogenesis and progression of various disorders, including renal diseases. Recent studies have revealed that circRNAs may serve as novel reliable biomarkers for the diagnosis and prognosis prediction of multiple kidney diseases, such as renal cell carcinoma (RCC), acute kidney injury (AKI), diabetic kidney disease (DKD), and other glomerular diseases. Furthermore, circRNAs expressed by intrinsic kidney cells are shown to play a substantial role in kidney injury, mostly reported in DKD and RCC. Herein, we review the biogenesis and biological functions of circRNAs, and summarize their roles as promising biomarkers and therapeutic targets in common kidney diseases.
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OBJECTIVE: Increasing the efficiency of early diagnosis using noninvasive biomarkers is crucial for enhancing the survival rate of lung cancer patients. We explore the differential expression of non-small cell lung cancer (NSCLC)-related long noncoding RNAs (lncRNAs) in urinary exosomes in NSCLC patients and normal controls to diagnose lung cancer. METHODS: A differential expression analysis between NSCLC patients and healthy controls was performed using microarrays. Gene ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were used to predict potential functions of lncRNAs in NSCLC. quantitative real-time PCR (QT-PCR) was used to verify microarray results. RESULTS: A total of 640 lncRNAs (70 up- and 570 down-regulated) were differentially expressed in NSCLC patients in comparison to healthy controls. Six lncRNAs were detected by QT-PCR. GO term and KEGG pathway analyses showed that differential lncRNAs were enriched in cellular component organization or biogenesis, as well as other biological processes and signaling pathways, such as the PI3K-AKT, FOXO, p53, and fatty acid biosynthesis. CONCLUSIONS: The differential lncRNAs in urinary exosomes are potential diagnostic biomarkers of NSCLC. The lncRNAs enriched in specific pathways may be associated with tumor cell proliferation, tumor cell apoptosis, and the cell cycle involved in the pathogenesis of NSCLC.
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Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Exossomos/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Idoso , Biomarcadores Tumorais/urina , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/urina , Estudos de Casos e Controles , Bases de Dados Genéticas , Detecção Precoce de Câncer , Exossomos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/urina , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , RNA Longo não Codificante/urina , UrináliseRESUMO
T Follicular helper (Tfh) cells promote germinal center (GC) B cell responses to develop effective humoral immunity against pathogens. However, dysregulated Tfh cells can also trigger autoantibody production and the development of autoimmune diseases. We report here that Tsc1, a regulator for mTOR signaling, plays differential roles in Tfh cell/GC B cell responses in the steady state and in immune responses to antigen immunization. In the steady state, Tsc1 in T cells intrinsically suppresses spontaneous GC-Tfh cell differentiation and subsequent GC-B cell formation and autoantibody production. In immune responses to antigen immunization, Tsc1 in T cells is required for efficient GC-Tfh cell expansion, GC-B cell induction, and antigen-specific antibody responses, at least in part via promoting GC-Tfh cell mitochondrial integrity and survival. Interestingly, in mixed bone marrow chimeric mice reconstituted with both wild-type and T cell-specific Tsc1-deficient bone marrow cells, Tsc1 deficiency leads to enhanced GC-Tfh cell differentiation of wild-type CD4 T cells and increased accumulation of wild-type T regulatory cells and T follicular regulatory cells. Such bystander GC-Tfh cell differentiation suggests a potential mechanism that could trigger self-reactive GC-Tfh cell/GC responses and autoimmunity via neighboring GC-Tfh cells.
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Autoimunidade , Diferenciação Celular/imunologia , Imunomodulação/genética , Células T Auxiliares Foliculares/imunologia , Células T Auxiliares Foliculares/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética , Animais , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoimunidade/genética , Autoimunidade/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína 1 do Complexo Esclerose Tuberosa/metabolismoRESUMO
Introduction: "U" route transforaminal percutaneous endoscopic lumbar discectomy (PELD) was introduced for lumbar spinal stenosis (LSS) combined with disc herniation (DH) treatment. This study aims to explore the efficacy and safety of "U" route PELD on chronic pain patients with LSS combined with DH. Methods: Degenerative LSS combined with DH patients who underwent "U" route PELD were reexamined, and 80 patients were recruited and followed up for 2 years. The other 80 healthy individuals who were age- and sex-matched to the patients without chronic pain were enrolled as healthy controls. Minimum dura sac cross-sectional area (mDCSA) by MRI, Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and modified MacNab outcomes were assessed. Emotional evaluation of pain catastrophizing and depression was documented with Pain Catastrophizing Scale (PCS) and Beck Depression Inventory (BDI), respectively, for patients before and after surgery and healthy individuals. Results: All patients were of the age range from 47 to 85 years, with an average of 59.5 ± 9.76 years. Symptoms duration was 114.6 ± 22.77 months, operation time was 87.7 ± 25.20 minutes, and the average hospital stay was 5.8 ± 2.81 days. Four patients quit, and hence, a total of 76 patients completed the follow-up. The results indicated that mDCSA was improved significantly after operation (p < 0.001), either low back and leg VAS or ODI decreased over time (p < 0.001), and the excellent-to-good rate was improved from 88.75% to 93.42% during postoperative 2 years (p < 0.05). Complications of dural tear, nerve root, or dysesthesia were reported in 5 patients, and all recovered after conservative therapy. The scores of pain catastrophizing were reduced after operation (p < 0.001), but no significance of BDI was found between patients and healthy controls (p > 0.05). Conclusions: The "U" route PELD seems an alternative to LSS combined with DH treatment, which might reach a better decompression and effectively improve chronic pain conditions. Still, the complications were potential and required further consideration.
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Dor Crônica/etiologia , Dor Crônica/terapia , Discotomia Percutânea/métodos , Discotomia/métodos , Endoscopia/métodos , Estenose Espinal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estenose Espinal/patologia , Resultado do TratamentoRESUMO
The marine bacterium Vibrio vulnificus causes potentially fatal bloodstream infections, typically in patients with chronic liver diseases. The inflammatory response and anti-bacterial function of phagocytes are crucial for limiting bacterial infection in the human hosts. How V. vulnificus affects macrophages after phagocytosis is unclear. In this report, we found that the bactericidal activity of macrophages to internalize V. vulnificus was dependent on mammalian target of rapamycin (mTOR) and NOD-like receptor (NLR) family pyrin domain containing 3 (NLRP3) interaction. Additionally, the NLRP3 expression was dependent on mTORC1 activation. Inhibited mTORC1 or absence of NLRP3 in macrophages impaired V. vulnificus-induced phagosome acidification and phagolysosome formation, leading to a reduction of intracellular bacterial clearance. mTORC1 signaling overactivation could increase NLRP3 expression and restore insufficient phagosome acidification. Together, these findings indicate that the intracellular bactericidal activity of macrophages responding to V. vulnificus infection is tightly controlled by the crosstalk of NLRP3 and mTOR and provide critical insight into the host bactericidal activity basis of clearance of V. vulnificus through lyso/phagosome.
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Diacylglycerol kinases (DGKs) play important roles in restraining diacylglycerol (DAG)-mediated signaling. Within the DGK family, the ζ isoform appears to be the most important isoform in T cells for controlling their development and function. DGKζ has been demonstrated to regulate T cell maturation, activation, anergy, effector/memory differentiation, defense against microbial infection, and antitumor immunity. Given its critical functions, DGKζ function should be tightly regulated to ensure proper signal transduction; however, mechanisms that control DGKζ function are still poorly understood. We report here that DGKζ dynamically translocates from the cytosol into the nuclei in T cells after TCR stimulation. In mice, DGKζ mutant defective in nuclear localization displayed enhanced ability to inhibit TCR-induced DAG-mediated signaling in primary T cells, maturation of conventional αßT and iNKT cells, and activation of peripheral T cells compared with WT DGKζ. Our study reveals for the first time nuclear sequestration of DGKζ as a negative control mechanism to spatially restrain it from terminating DAG mediated signaling in T cells. Our data suggest that manipulation of DGKζ nucleus-cytosol shuttling as a novel strategy to modulate DGKζ activity and immune responses for treatment of autoimmune diseases and cancer.
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Diacilglicerol Quinase/metabolismo , Diglicerídeos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/fisiologia , Animais , Doenças Autoimunes/metabolismo , Diferenciação Celular/fisiologia , Núcleo Celular/metabolismo , Citosol/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/metabolismoRESUMO
Vibrio vulnificus (V. vulnificus) is an estuarine bacterium that is capable of causing rapidly fatal infection in humans. Proper polarization and bactericidal activity of macrophages play essential roles in defending against invading pathogens. How macrophages limit V. vulnificus infection remains not well understood. Here we report that tuberous sclerosis complex 1 (TSC1) is crucial for the regulation of V. vulnificus-induced macrophage polarization, bacterial clearance, and cell death. Mice with myeloid-specific deletion of TSC1 exhibit a significant reduction of survival time after V. vulnificus infection. V. vulnificus infection induces both M1 and M2 polarization. However, TSC1 deficient macrophages show enhanced M1 response to V. vulnificus infection. Interestedly, the absence of TSC1 in myeloid cells results in impaired bacterial clearance both in vivo and in vitro after V. vulnificus infection. Inhibition of the mammalian target of rapamycin (mTOR) activity significantly reverses V. vulnificus-induced hypersensitive M1 response and resistant bactericidal activity both in wild-type and TSC1-deficient macrophages. Moreover, V. vulnificus infection causes cell death of macrophages, possibly contributes to defective of bacterial clearance, which also exhibits in a mTORC1-dependent manner. These findings highlight an essential role for the TSC1-mTOR signaling in the regulation of innate immunity against V. vulnificus infection.
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Esclerose Tuberosa , Vibrioses , Animais , Macrófagos , Camundongos , Proteína 1 do Complexo Esclerose TuberosaRESUMO
BACKGROUND AND AIM: Thrombopoietin receptor agonists (TPO-RAs) have been shown to be safe and effective for adults with chronic immune thrombocytopenia (ITP). The aim of this meta-analysis is to assess the efficacy and safety of thrombopoietin receptor agonists for children with chronic ITP. MATERIALS AND METHODS: Clinical randomized controlled trials (RCTs) evaluating the efficacy and safety of TPO-RAs in pediatric ITP patients published up to June 2017 were retrieved from PubMed, Cochrane Library, and Embase databases. Relevant data were extracted, and the Physiotherapy Evidence Database scale was used to assess the methodological quality. Stata/SE 12.0 was used to perform a meta-analysis. RESULTS: Seven RCTs were included, with 238 patients and 107 patients in the TPO-RA group and the control group, respectively. Assessing efficacy, better results were found in the TPO-RA group for the rate of overall platelet response, durable response, and rescue medication needed. Furthermore, the TPO-RA group yielded superior results in the incidence of clinically significant bleeding events but had a comparable result in the incidence of any bleeding events and severe bleeding events. No significant difference was found between the two groups in health-related quality of life and parental burden. Assessing safety, no significant difference was found between the two groups in the incidence of any adverse events and severe adverse events. CONCLUSIONS: TPO-RAs are effective and safe agents for the treatment of chronic ITP in pediatric patients. Eltrombopag appears to be better than romiplostim in terms of the rate of rescue medication needed and clinically significant bleeding events.
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Vibrio vulnificus (V. vulnificus), a Gram-negative marine bacterium, can cause life-threatening primary septicemia, especially in patients with liver diseases. How V. vulnificus affects the liver and how it acts on macrophages are not well understood. In this report, we demonstrated that V. vulnificus infection causes a strong inflammatory response, marked expansion of liver-resident macrophages, and liver damage in mice. We demonstrated further that V. vulnificus activates mTOR in macrophages and inhibition of mTOR differentially regulates V. vulnificus induced inflammatory responses, suggesting the possibility of targeting mTOR as a strategy to modulate V. vulnificus induced inflammatory responses.
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Macrófagos/metabolismo , Macrófagos/microbiologia , Serina-Treonina Quinases TOR/metabolismo , Vibrio vulnificus/fisiologia , Animais , Ativação Enzimática , Inflamação/microbiologia , Células de Kupffer/citologia , Fígado/imunologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neutrófilos/citologia , Vibrioses/complicaçõesRESUMO
Signals from the T-cell receptor (TCR) and γ-chain cytokine receptors play crucial roles in initiating activation and effector/memory differentiation of CD8 T-cells. We report here that simultaneous deletion of both diacylglycerol kinase (DGK) α and ζ (DKO) severely impaired expansion of CD8 effector T cells and formation of memory CD8 T-cells after Listeria monocytogenes infection. Moreover, ablation of both DGKα and ζ in preformed memory CD8 T-cells triggered death and impaired homeostatic proliferation of these cells. DKO CD8 T-cells were impaired in priming due to decreased expression of chemokine receptors and migration to the draining lymph nodes. Moreover, DKO CD8 T-cells were unexpectedly defective in NFκB-mediated miR-155 transcript, leading to excessive SOCS1 expression and impaired γ-chain cytokine signaling. Our data identified a DGK-NFκB-miR-155-SOCS1 axis that bridges TCR and γ-chain cytokine signaling for robust CD8 T-cell primary and memory responses to bacterial infection.
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Linfócitos T CD8-Positivos/imunologia , Diacilglicerol Quinase/imunologia , MicroRNAs/imunologia , NF-kappa B/imunologia , Animais , Diferenciação Celular/imunologia , Quimiotaxia de Leucócito/imunologia , Memória Imunológica/imunologia , Listeria monocytogenes , Listeriose/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/imunologiaRESUMO
Development of effective immune therapies for cancer patients requires better understanding of hurdles that prevent the generation of effective antitumor immune responses. Administration of α-galactosylceramide (α-GalCer) in animals enhances antitumor immunity via activation of the invariant NKT (iNKT) cells. However, repeated injections of α-GalCer result in long-term unresponsiveness or anergy of iNKT cells, severely limiting its efficacy in tumor eradication. The mechanisms leading to iNKT cell anergy remain poorly understood. We report in this study that the tuberous sclerosis 1 (TSC1), a negative regulator of mTOR signaling, plays a crucial role in iNKT cell anergy. Deficiency of TSC1 in iNKT cells results in resistance to α-GalCer-induced anergy, manifested by increased expansion of and cytokine production by iNKT cells in response to secondary Ag stimulation. It is correlated with impaired upregulation of programmed death-1, Egr2, and Grail. Moreover, TSC1-deficient iNKT cells display enhanced antitumor immunity in a melanoma lung metastasis model. Our data suggest targeting TSC1/2 as a strategy for boosting antitumor immune therapy.
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Anergia Clonal/imunologia , Melanoma Experimental/imunologia , Células T Matadoras Naturais/imunologia , Esclerose Tuberosa/imunologia , Animais , Linhagem Celular Tumoral , Citocinas/imunologia , Citocinas/metabolismo , Proteína 2 de Resposta de Crescimento Precoce/genética , Proteína 2 de Resposta de Crescimento Precoce/imunologia , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Citometria de Fluxo , Expressão Gênica/imunologia , Homeostase/genética , Homeostase/imunologia , Immunoblotting , Imunoterapia Adotiva , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células T Matadoras Naturais/metabolismo , Células T Matadoras Naturais/transplante , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esclerose Tuberosa/genética , Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/imunologia , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The engagement of the T cell receptor (TCR) induces the generation of diacylglycerol (DAG), an important second messenger activating both the Ras/Erk and PKCθ/NFκB pathways. DAG kinases (DGKs) participate in the metabolism of DAG by converting it to phosphatidic acid. DGKζ has been demonstrated to be able to inhibit DAG signaling following TCR engagement. Deficiency of DGKζ increases the sensitivity of T cells to TCR stimulation, resulting in enhanced T cell activation ex vivo and in vivo. However, the mechanisms that control DGKζ expression are poorly understood. Here we demonstrate that DGKζ mRNA is a direct target of a cellular microRNA miR-34a. The DGKζ transcript is decreased, whereas the primary miR-34a is upregulated upon TCR stimulation. Ectopic miR-34a expression suppresses DGKζ protein expression through the seed match binding to both the 3' untranslated region and coding region of DGKζ mRNA, leading to increased ERK1/2 phosphorylation and surface expression of the T cell activation marker CD69 following TCR cross-linking. In contrast, overexpression of a miR-34a competitive inhibitor increases DGKζ expression and suppresses TCR-mediated T cell activation. Together, our data demonstrate that miR-34a is a negative regulator for DGKζ and may play an important role in regulating T cell activation.
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Diacilglicerol Quinase/metabolismo , MicroRNAs/metabolismo , Linfócitos T/metabolismo , Animais , Diacilglicerol Quinase/genética , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T/imunologiaRESUMO
Interleukin-4 (IL-4) plays an important role in the pathogenesis of cancer. The -590C/T polymorphism in the IL-4 gene has been implicated in susceptibility to cancer, but the results have been inconclusive. The aim of this study was to analyze the association between this polymorphism with the risk of cancer by meta-analysis. PubMed, Embase, CNKI, and Wanfang databases were searched for all publications concerning the association between this polymorphism and cancer risk. Statistical analyses were analyzed by using RevMan 4.2 and STATA10.0 softwares. A total of 8,715 cases and 9,532 controls in 23 case-control studies were included. The results suggested that there was no significant association between IL-4 -590C/T polymorphism and cancer risks (TT + TC vs. CC: OR = 0.97, 95 % CI = 0.90-1.04, P = 0.36). In the subgroup analysis by ethnicity, no significant association was detected in Asians and Caucasians. In the subgroup analysis by cancer types, no significant association was found in gastric cancer and colorectal cancer. The current meta-analysis suggested that the -590C/T polymorphism in the IL-4 gene might not be associated with increased/decreased risk of cancer. The -590C/T polymorphism might be not a risk factor for cancers.
Assuntos
Interleucina-4/genética , Neoplasias/genética , Povo Asiático/genética , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Risco , Neoplasias Gástricas/genética , População Branca/genéticaRESUMO
T-cell anergy is a state of T cells that is hyporesponsive to stimulation via the T-cell receptor and costimulatory molecules and is thought to be important for self-tolerance. How T-cell anergy is regulated is still poorly understood. We report here that tuberous sclerosis (TSC)1 is critical for T-cell anergy. Deficiency of TSC1 resulted in enhanced T-cell proliferation and cytokine production in the absence of cluster of differentiation (CD)28-mediated costimulation, accompanied by enhanced T-cell metabolism. Resistance of TSC1-deficient T cells to anergy is correlated with increased signaling through the mammalian target of rapamycin complex (mTORC)1 and can be reverted by treatment of these cells with mTORC1 inhibitor rapamycin. Expression of the inducible costimulator (ICOS) is increased in TSC1-deficient T cells, which can be inhibited by rapamycin. Simultaneous blockade of both CD28 and ICOS costimulation partially restored sensitivity of TSC1-deficient T cells to anergy induction. Together, our data indicate that TSC1 is crucial for T-cell anergy by inhibiting mTORC1 signaling through both ICOS-dependent and -independent mechanisms.
Assuntos
Anergia Clonal/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Proteínas Supressoras de Tumor/imunologia , Animais , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Divisão Celular/imunologia , Metabolismo Energético/imunologia , Tolerância Imunológica/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Ativação Linfocitária/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Knockout , Complexos Multiproteicos , Proteínas/imunologia , Proteínas/metabolismo , Transdução de Sinais/imunologia , Linfócitos T/metabolismo , Serina-Treonina Quinases TOR , Proteína 1 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismoRESUMO
Activation of the transcription factor NF-κB is critical for cytokine production and T cell survival after TCR engagement. The effects of persistent NF-κB activity on T cell function and survival are poorly understood. In this study, using a murine model that expresses a constitutively active form of inhibitor of NF-κB kinase ß (caIKKß) in a T cell-specific manner, we demonstrate that chronic inhibitor of NF-κB kinase ß signaling promotes T cell apoptosis, attenuates responsiveness to TCR-mediated stimulation in vitro, and impairs T cell responses to bacterial infection in vivo. caIKKß T cells showed increased Fas ligand expression and caspase-8 activation, and blocking Fas/Fas ligand interactions enhanced cell survival. T cell unresponsiveness was associated with defects in TCR proximal signaling and elevated levels of B lymphocyte-induced maturation protein 1, a transcriptional repressor that promotes T cell exhaustion. caIKKß T cells also showed a defect in IL-2 production, and addition of exogenous IL-2 enhanced their survival and proliferation. Conditional deletion of B lymphocyte-induced maturation protein 1 partially rescued the sensitivity of caIKKß T cells to TCR triggering. Furthermore, adoptively transferred caIKKß T cells showed diminished expansion and increased contraction in response to infection with Listeria monocytogenes expressing a cognate Ag. Despite their functional defects, caIKKß T cells readily produced proinflammatory cytokines, and mice developed autoimmunity. In contrast to NF-κB's critical role in T cell activation and survival, our study demonstrates that persistent IKK-NF-κB signaling is sufficient to impair both T cell function and survival.