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Autophagy-related protein 7 (ATG7) is an essential autophagy effector enzyme. Although it is well known that autophagy plays crucial roles in the infections with various viruses including influenza A virus (IAV), function and underlying mechanism of ATG7 in infection and pathogenesis of IAV remain poorly understood. Here, in vitro studies showed that ATG7 had profound effects on replication of IAV. Depletion of ATG7 markedly attenuated the replication of IAV, whereas overexpression of ATG7 facilitated the viral replication. ATG7 conditional knockout mice were further employed and exhibited significantly resistant to viral infections, as evidenced by a lower degree of tissue injury, slower body weight loss, and better survival, than the wild type animals challenged with either IAV (RNA virus) or pseudorabies virus (DNA virus). Interestingly, we found that ATG7 promoted the replication of IAV in autophagy-dependent and -independent manners, as inhibition of autophagy failed to completely block the upregulation of IAV replication by ATG7. To determine the autophagy-independent mechanism, transcriptome analysis was utilized and demonstrated that ATG7 restrained the production of interferons (IFNs). Loss of ATG7 obviously enhanced the expression of type I and III IFNs in ATG7-depleted cells and mice, whereas overexpression of ATG7 impaired the interferon response to IAV infection. Consistently, our experiments demonstrated that ATG7 significantly suppressed IRF3 activation during the IAV infection. Furthermore, we identified long noncoding RNA (lncRNA) GAPLINC as a critical regulator involved in the promotion of IAV replication by ATG7. Importantly, both inactivation of IRF3 and inhibition of IFN response caused by ATG7 were mediated through control over GAPLINC expression, suggesting that GAPLINC contributes to the suppression of antiviral immunity by ATG7. Together, these results uncover an autophagy-independent mechanism by which ATG7 suppresses host innate immunity and establish a critical role for ATG7/GAPLINC/IRF3 axis in regulating IAV infection and pathogenesis.
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Vírus da Influenza A , Influenza Humana , Viroses , Animais , Humanos , Camundongos , Imunidade Inata , Interferons , Replicação ViralRESUMO
Effective viral clearance requires fine-tuned immune responses to minimize undesirable inflammatory responses. Circular RNAs (circRNAs) are a class of non-coding RNAs that are abundant and highly stable, formed by backsplicing pre-mRNAs, and expressed ubiquitously in eukaryotic cells, emerging as critical regulators of a plethora of signaling pathways. Recent progress in high-throughput sequencing has enabled a better understanding of the physiological and pathophysiological functions of circRNAs, overcoming the obstacle of the sequence overlap between circRNAs and their linear cognate mRNAs. Some viruses also encode circRNAs implicated in viral replication or disease progression. There is increasing evidence that viral infections dysregulate circRNA expression and that the altered expression of circRNAs is critical in regulating viral infection and replication. circRNAs were shown to regulate gene expression via microRNA and protein sponging or via encoding small polypeptides. Recent studies have also highlighted the potential role of circRNAs as promising diagnostic and prognostic biomarkers, RNA vaccines and antiviral therapy candidates due to their higher stability and lower immunogenicity. This review presents an up-to-date summary of the mechanistic involvement of circRNAs in innate immunity against viral infections, the current understanding of their regulatory roles, and the suggested applications.
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RNA Circular , Viroses , Humanos , RNA Circular/genética , Imunidade Inata , Viroses/genética , Progressão da Doença , Células EucarióticasRESUMO
Respiratory syncytial virus (RSV) is the leading cause of respiratory illness in ruminants and infants. The G glycoprotein of RSV serves as the viral attachment ligand. Despite currently available vaccines, RSV immunity is insufficient, and re-infections occur. Vaccine studies employing the G-protein's 174-187 amino acids, representing the immunodominant domain, have protected mice and calves against infections. To investigate the causes of vaccination failure, we designed four synthetic peptides for the ruminant RSV isolates (391-2, Maryland-BRSV, European-BRSV, and ORSV) using the immune-dominant sequence and vaccinated mice groups with them. The produced antibodies targeting each peptide were evaluated using ELISA and flow cytometry to determine their reactivity against the linear antigen and the native form of the G protein, respectively. Antibodies responded to homologous and heterologous peptides as determined by ELISA. Using flow cytometry-analysis targeting the natively folded protein, most generated antibodies reacted only with their homologous strain. However, antibodies raised to 391-2 peptide reacted with homologous and heterologous Maryland-BRSV viral epitopes. Accordingly, inadequate immunity and recurring RSV infections might be attributed to variations of antibodies targeting the immunodominant region of the G-protein.
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Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Bovinos , Animais , Camundongos , Epitopos Imunodominantes , Camundongos Endogâmicos BALB C , Aminoácidos , Formação de Anticorpos , Anticorpos Antivirais , Proteínas de Ligação ao GTPRESUMO
Circular RNAs (circRNAs) are an important subclass of noncoding RNAs implicated in the regulation of multiple biological processes. However, the functional involvement of circRNAs in the pathogenesis of influenza A viruses (IAVs) remains largely unknown. Here, we employed RNA sequencing (RNA-Seq) to examine the differentially expressed circRNAs in mouse lung tissues challenged or not challenged with IAV to evaluate the impact of viral infection on circRNAs in vivo. We observed that 413 circRNAs exhibited significantly altered levels following IAV infection. Among these, circMerTK, the derivative of myeloid-epithelial-reproductive tyrosine kinase (MerTK) pre-mRNA, was highly induced by IAV. Interestingly, circMerTK expression was also increased upon infection with multiple DNA and RNA viruses in human and animal cell lines, and thus it was selected for further studies. Poly(I:C) and interferon ß (IFN-ß) stimulated circMerTK expression, while RIG-I knockout and IFNAR1 knockout cell lines failed to elevate circMerTK levels after IAV infection, demonstrating that circMerTK is regulated by IFN signaling. Furthermore, circMerTK overexpression or silencing accelerated or impeded IAV and Sendai virus replication, respectively. Silencing circMerTK enhanced the production of type I IFNs and interferon-stimulating genes (ISGs), whereas circMerTK overexpression suppressed their expression at both the mRNA and protein levels. Notably, altering circMerTK expression had no effect on the MerTK mRNA level in cells infected or not infected with IAV, and vice versa. In addition, human circMerTK and mouse homologs functioned similarly in antiviral responses. Together, these results identify circMerTK as an enhancer of IAV replication through suppression of antiviral immunity. IMPORTANCE CircRNAs are an important class of noncoding RNAs characterized by a covalently closed circular structure. CircRNAs have been proven to impact numerous cellular processes, where they conduct specialized biological activities. In addition, circRNAs are believed to play a crucial role in regulating immune responses. Nevertheless, the functions of circRNAs in the innate immunity against IAV infection remain obscure. In this study, we employed transcriptomic analysis to investigate the alterations in circRNAs expression following IAV infection in vivo. It was found that expression of 413 circRNAs was significantly altered, of which 171 were upregulated, and 242 were downregulated following the IAV infection. Interestingly, circMerTK was identified as a positive regulator of IAV replication in both human and mouse hosts. CircMerTK was shown to influence IFN-ß production and its downstream signaling, enhancing IAV replication. This finding provides new insights into the critical roles of circRNAs in regulating antiviral immunity.
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MIR155HG encodes a precursor RNA of microRNA-155 (miRNA-155). We previously identified this RNA also as a long noncoding RNA (lncRNA) that we call lncRNA-155. To define the functions of miRNA-155 and lncRNA-155, we generated miRNA-155 knockout (KO) mice lacking only 19 bp of the miRNA-155 core sequence without affecting the expression of lncRNA-155. Surprisingly, compared with the miRNA-155KO mice, previously generated lncRNA-155KO mice were more susceptible to both influenza virus (RNA virus) and pseudorabies virus (DNA virus) infection, as characterized by lower survival rate, higher body weight loss, and higher viral load. We found that miRNA-155-5p enhanced antiviral responses by positively regulating activation of signal transducer and activator of transcription 1 (STAT1), but the STAT1 activity differed greatly in the animals (lncRNA-155KO < miRNA-155KO < wild type). In line with this, expression levels of several critical interferon-stimulated genes (ISGs) were also significantly different (lncRNA-155KO < miRNA-155KO < wild type). We found that lncRNA-155 augmented interferon beta (IFN-ß) production during the viral infection, but miRNA-155 had no significant effect on the virus-induced IFN-ß expression. Furthermore, we observed that lncRNA-155 loss in mice resulted in dramatic inhibition of virus-induced activation of interferon regulatory factor 3 compared to both miRNA-155KO and wild-type (WT) animals. Moreover, lncRNA-155 still significantly suppressed the viral infection even though the miRNA-155 derived from lncRNA-155 was deleted or blocked. These results reveal that lncRNA-155 and miRNA-155 regulate antiviral responses through distinct mechanisms, indicating a bivalent role for MIR155HG in innate immunity. IMPORTANCE Here, we found that lncRNA-155KO mice lacking most of the lncRNA-155 sequences along with pre-miRNA-155, were more susceptible to influenza virus or pseudorabies virus infection than miRNA-155KO mice lacking only 19 bp of the miRNA-155 core sequence without affecting the expression of lncRNA-155, as evidenced by faster body weight loss, poorer survival, and higher viral load, suggesting an additional role of lncRNA-155 in regulating viral pathogenesis besides via processing miRNA-155. Congruously, miRNA-155-deleted lncRNA-155 significantly attenuated the viral infection. Mechanistically, we demonstrated miRNA-155-5p potentiated antiviral responses by promoting STAT1 activation but could not directly regulate the IFN-ß expression. In contrast, lncRNA-155 enhanced virus-induced IFN-ß production by regulating the activation of interferon regulatory factor 3. This finding reveals a bivalent role of MIR155HG in regulating antiviral responses through encoding lncRNA-155 and miRNA-155-5p and provides new insights into complicated mechanisms underlying interaction between virus and host innate immunity.
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MicroRNAs , RNA Longo não Codificante , Viroses , Vírus , Animais , Camundongos , Antivirais , RNA Longo não Codificante/genética , Fator Regulador 3 de Interferon/metabolismo , Replicação Viral/genética , Imunidade Inata/genética , Interferon beta/genética , MicroRNAs/genética , Vírus/genética , Redução de PesoRESUMO
Spleen tyrosine kinase (Syk) has recently come forth as a critical regulator of innate immune response. Previous studies identify Syk as a key kinase for STAT1 activation at the early stage of influenza A virus (IAV) infection that is involved in initial antiviral immunity. However, the involvement of Syk in host antiviral immunity during the late phase of IAV infection and its effect on pathogenesis of the virus remain unknown. Here, we found through time course studies that Syk restrained antiviral immune response at the late stage of IAV infection, thereby promoting viral replication. Depletion of Syk suppressed IAV replication in vitro, whereas ectopic expression of Syk facilitated viral replication. Moreover, Syk-deficient mice were employed, and we observed that knockout of Syk rendered mice more resistant to IAV infection, as evidenced by a lower degree of lung injury, slower body weight loss, and an increased survival rate of Syk knockout mice challenged with IAV. Furthermore, we revealed that Syk repressed the interferon response at the late stage of viral infection. Loss of Syk potentiated the expression of type I and III interferons in both Syk-depleted cells and mice. Mechanistically, Syk interacted with TBK1 and modulated its phosphorylation status, thereby impeding TBK1 activation and restraining innate immune signaling that governs interferon response. Together, these findings unveil a role of Syk in temporally regulating host antiviral immunity and advance our understanding of complicated mechanisms underlying regulation of innate immunity against viral invasion. IMPORTANCE Innate immunity must be tightly controlled to eliminate invading pathogens while avoiding autoimmune or inflammatory diseases. Syk is essential for STAT1 activation at the early stage of IAV infection, which is critical for initial antiviral responses. Surprisingly, here a time course study showed that Syk suppressed innate immunity during late phases of IAV infection and thereby promoted IAV replication. Syk deficiency enhanced the expression of type I and III interferons, inhibited IAV replication, and rendered mice more resistant to IAV infection. Syk impaired innate immune signaling through impeding TBK1 activation. These data reveal that Syk participates in the initiation of antiviral defense against IAV infection and simultaneously contributes to the restriction of innate immunity at the late stage of viral infection, suggesting that Syk serves a dual function in regulating antiviral responses. This finding provides new insights into complicated mechanisms underlying interaction between virus and host immune system.
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Imunidade Inata , Vírus da Influenza A , Infecções por Orthomyxoviridae , Animais , Antivirais/metabolismo , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Interferons/metabolismo , Camundongos , Infecções por Orthomyxoviridae/enzimologia , Infecções por Orthomyxoviridae/imunologia , Quinase Syk/genética , Quinase Syk/imunologia , Replicação ViralRESUMO
Long noncoding RNAs (lncRNAs) are involved in numerous cellular processes. Increasing evidence suggests that some lncRNAs function in immunity through various complex mechanisms. However, implication of a large fraction of lncRNAs in antiviral innate immunity remains uncharacterized. Here, we identified an lncRNA called lncRNA IFITM4P that was transcribed from interferon-induced transmembrane protein 4 pseudogene (IFITM4P), a pseudogene belonging to the interferon-induced transmembrane protein (IFITM) family. We found that expression of lncRNA IFITM4P was significantly induced by infection with several viruses, including influenza A virus (IAV). Importantly, lncRNA IFITM4P acted as a positive regulator of innate antiviral immunity. Ectopic expression of lncRNA IFITM4P significantly suppressed IAV replication in vitro, whereas IFITM4P deficiency promoted viral production. We further observed that expression of lncRNA IFITM4P was upregulated by interferon (IFN) signaling during viral infection, and altering the expression of this lncRNA had significant effects on the mRNA levels of several IFITM family members, including IFITM1, IFITM2, and IFITM3. Moreover, lncRNA IFITM4P was identified as a target of the microRNA miR-24-3p, which represses mRNA of IFITM1, IFITM2, and IFITM3. The experiments demonstrated that lncRNA IFITM4P was able to cross-regulate the expression of IFITM family members as a competing endogenous RNA (ceRNA), leading to increased stability of these IFITM mRNAs. Together, our results reveal that lncRNA IFITM4P, as a ceRNA, is involved in innate immunity against viral infection through the lncRNA IFITM4P-miR-24-3p-IFITM1/2/3 regulatory network. IMPORTANCE lncRNAs play important roles in various biological processes, but their involvement in host antiviral responses remains largely unknown. In this study, we revealed that the pseudogene IFITM4P belonging to the IFITM family can transcribe a functional long noncoding RNA termed lncRNA IFITM4P. Importantly, results showed that lncRNA IFITM4P was involved in innate antiviral immunity, which resembles some interferon-stimulated genes (ISGs). Furthermore, lncRNA IFITM4P was identified as a target of miR-24-3p and acts as a ceRNA to inhibit the replication of IAV through regulating the mRNA levels of IFITM1, IFITM2, and IFITM3. These data provide new insight into the role of a previously uncharacterized lncRNA encoded by a pseudogene in the host antiviral response and a better understanding of the IFITM antiviral network.
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Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Imunidade Inata/genética , Vírus da Influenza A/imunologia , Proteínas de Membrana/genética , RNA Longo não Codificante/genética , Células A549 , Animais , Cães , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno/imunologia , Humanos , Vírus da Influenza A/genética , Interferons/genética , Células K562 , Células Madin Darby de Rim Canino , Proteínas de Membrana/imunologia , RNA Longo não Codificante/imunologia , Transdução de Sinais , Replicação ViralRESUMO
Viral infections can cause rampant disease in human beings, ranging from mild to acute, that can often be fatal unless resolved. An acute viral infection is characterized by sudden or rapid onset of disease, which can be resolved quickly by robust innate immune responses exerted by the host or, instead, may kill the host. Immediately after viral infection, elements of innate immunity, such as physical barriers, various phagocytic cells, group of cytokines, interferons (IFNs), and IFN-stimulated genes, provide the first line of defense for viral clearance. Innate immunity not only plays a critical role in rapid viral clearance but can also lead to disease progression through immune-mediated host tissue injury. Although elements of antiviral innate immunity are armed to counter the viral invasion, viruses have evolved various strategies to escape host immune surveillance to establish successful infections. Understanding complex mechanisms underlying the interaction between viruses and host's innate immune system would help develop rational treatment strategies for acute viral infectious diseases. In this review, we discuss the pathogenesis of acute infections caused by viral pathogens and highlight broad immune escape strategies exhibited by viruses.
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Complicated production procedures and superior characteristics of nano-sized sulfur elevate its price to 25-40 fold higher than micrograde kind. Also, natural gas hydrogen sulfide levels are restricted because of its toxic environmental consequences. Thioalkalivibrio versutus is a polyextremophilic industrial autotroph with high natural gas desulfurization capability. Here, nanometric (>50 nm) sulfur bioproduction using T. versutus while desulfurizing natural gas was validated. Also, this production was enhanced by 166.7% via lowering sulfate production by 55.1%. A specially-developed CRISPR system, with 42% editing efficiency, simplified the genome editing workflow scheme for this challenging bacterium. In parallel, sulfur metabolism was uncovered using proteins mining and transcriptome studies for defining sulfate-producing key genes (heterodisulfide reductase-like complex, sulfur dioxygenase, sulfite dehydrogenase and sulfite oxidase). This study provided cost-effective nanometric sulfur production and improved this production using a novel CRISPR strategy, which could be suitable for industrial polyextremophiles, after uncovering sulfur pathways in T. versutus.
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Ectothiorhodospiraceae , Oxirredução , Sulfatos , EnxofreRESUMO
Influenza A virus (IAV) infection regulates the expression of numerous host genes. However, the precise mechanism underlying implication of these genes in IAV pathogenesis remains largely unknown. Here, we employed isobaric tags for relative and absolute quantification (iTRAQ) to identify host proteins regulated by IAV infection. iTRAQ analysis of mouse lungs infected or uninfected with IAV showed a total of 167 differentially upregulated proteins in response to the viral infection. Interestingly, we observed that p27Kip1, a potent cyclin-dependent kinase inhibitor, was markedly induced by IAV both at mRNA and protein levels through in vitro and in vivo studies. Furthermore, it was shown that innate immune signalling positively regulated p27Kip1 expression in response to IAV infection. Ectopic expression of p27Kip1 in A549 cells dramatically inhibited IAV replication, whereas, p27Kip1 knockdown significantly enhanced the virus replication. in vivo experiments demonstrated that p27Kip1 knockout (KO) mice were more susceptible to IAV than wild-type (WT) mice: exhibiting higher viral load in lung tissue, faster body-weight loss, reduced survival rate and more severe organ damage. Moreover, we found that p27Kip1 overexpression facilitated the degradation of viral NS1 protein, caused a dramatic STAT1 activation and promoted the expression of IFN-ß and several critical antiviral interferon-stimulated genes (ISGs). Increased p27Kip1 expression also restricted infections of several other viruses. Conversely, IAV-infected p27Kip1 KO mice exhibited a sharp increase in NS1 protein accumulation, reduced level of STAT1 activation and decreased expression of IFN-ß and the ISGs in the lung compared to WT animals. These findings reveal a key role of p27Kip1 in enhancing antiviral innate immunity.
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Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Imunidade Inata , Vírus da Influenza A Subtipo H1N1/imunologia , Infecções por Orthomyxoviridae/imunologia , Animais , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p27/biossíntese , Inibidor de Quinase Dependente de Ciclina p27/genética , Interações Hospedeiro-Patógeno , Humanos , Vírus da Influenza A Subtipo H1N1/metabolismo , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/genética , Influenza Humana/imunologia , Influenza Humana/metabolismo , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Transdução de Sinais , Regulação para Cima , Proteínas não Estruturais Virais/metabolismo , Viroses/imunologia , Viroses/metabolismo , Viroses/virologia , Replicação ViralRESUMO
Long noncoding RNAs (lncRNAs) are single-stranded RNA molecules longer than 200 nt that regulate many cellular processes. MicroRNA 155 host gene (MIR155HG) encodes the microRNA (miR)-155 that regulates various signalling pathways of innate and adaptive immune responses against viral infections. MIR155HG also encodes a lncRNA that we call lncRNA-155. Here, we observed that expression of lncRNA-155 was markedly upregulated during influenza A virus (IAV) infection both in vitro (several cell lines) and in vivo (mouse model). Interestingly, robust expression of lncRNA-155 was also induced by infections with several other viruses. Disruption of lncRNA-155 expression in A549 cells diminished the antiviral innate immunity against IAV. Furthermore, knockout of lncRNA-155 in mice significantly increased IAV replication and virulence in the animals. In contrast, overexpression of lncRNA-155 in human cells suppressed IAV replication, suggesting that lncRNA-155 is involved in host antiviral innate immunity induced by IAV infection. Moreover, we found that lncRNA-155 had a profound effect on expression of protein tyrosine phosphatase 1B (PTP1B) during the infection with IAV. Inhibition of PTP1B by lncRNA-155 resulted in higher production of interferon-beta (IFN-ß) and several critical interferon-stimulated genes (ISGs). Together, these observations reveal that MIR155HG derived lncRNA-155 can be induced by IAV, which modulates host innate immunity during the virus infection via regulation of PTP1B-mediated interferon response.
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Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Vírus da Influenza A/imunologia , MicroRNAs/genética , Infecções por Orthomyxoviridae/genética , RNA Longo não Codificante/genética , Células A549 , Animais , Citocinas/genética , Citocinas/imunologia , Regulação da Expressão Gênica , Células HEK293 , Interações Hospedeiro-Patógeno/genética , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/patogenicidade , Influenza Humana/genética , Influenza Humana/imunologia , Influenza Humana/virologia , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/imunologia , Interferon beta/genética , Interferon beta/imunologia , Interferon gama/genética , Interferon gama/imunologia , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Células NIH 3T3 , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/virologia , Células RAW 264.7 , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/imunologia , Transdução de Sinais , Análise de Sobrevida , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/imunologia , Ubiquitinas/genética , Ubiquitinas/imunologia , Replicação Viral/genética , Replicação Viral/imunologiaRESUMO
Objective: Despite extensive studies, the precise mechanism underlying spondyloarthritis, especially ankylosing spondylitis, remains elusive. This study aimed to develop an ideal animal model for an insight into mechanism of spondyloarthritis and functional relevance of SOCS3 in spondyloarthritis. Methods: Since SOCS3 is a major regulator of IL23-STAT3 signaling, we generated SOCS3 knockdown transgenic (TG) mice for development of an animal model of spondyloarthritis. A hydrodynamic delivery method was employed to deliver minicircle DNA expressing IL23 (mc-IL23) into wild-type (WT) and the TG mice. Knockdown/overexpression systems mediated by lentivirus and retrovirus were used to determine whether SOCS3 regulated osteoblast differentiation. Results: Forced expression of IL23 induced severe joint destruction and extensive bone loss in SOCS3 knockdown TG mice, while this treatment only caused moderate symptoms in WT mice. Furthermore, severe spondyloarthritis was found in IL23-injected TG mice as compared to mild disease observed in WT controls under same condition. Moreover, our studies showed that IL23 promoted osteoblast differentiation via activation of STAT3 pathway and disruption of SOCS3 expression greatly increased phosphorylation of STAT3. In addition, silencing SOCS3 resulted in enhanced osteoblast differentiation through activation of Smad1/5/9 signaling, as evidenced by elevated phosphorylation level of Smad1/5/9. Experiments further demonstrated that SOCS3 interacted with Smad1 and thus suppressed the BMP2-Smad signaling. Conclusions: The results reveal that SOCS3 is involved in IL23-induced spondyloarthritis and acts as a key regulator of osteoblast differentiation, and suggest that SOCS3 knockdown TG mice may be an ideal animal model for further studies of spondyloarthritis.
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Diferenciação Celular , Interleucina-23 , Osteoblastos , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem Celular , DNA Circular/efeitos adversos , DNA Circular/genética , DNA Circular/imunologia , DNA Circular/farmacologia , Modelos Animais de Doenças , Inativação Gênica , Interleucina-23/efeitos adversos , Interleucina-23/genética , Interleucina-23/imunologia , Camundongos , Camundongos Knockout , Osteoblastos/imunologia , Osteoblastos/patologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Espondilite Anquilosante/induzido quimicamente , Espondilite Anquilosante/genética , Espondilite Anquilosante/imunologia , Espondilite Anquilosante/patologia , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/imunologiaRESUMO
Virus infected host cells serve as a central immune ecological niche during viral infection and replication and stimulate the host immune response via molecular signaling. The viral infection and multiplication process involves complex intracellular molecular interactions between viral components and the host factors. Various types of host cells are also involved to modulate immune factors in delicate and dynamic equilibrium to maintain a balanced immune ecosystem in an infected host tissue. Antiviral host arsenals are equipped to combat or eliminate viral invasion. However, viruses have evolved with strategies to counter against antiviral immunity or hijack cellular machinery to survive inside host tissue for their multiplication. However, host immune systems have also evolved to neutralize the infection; which, in turn, either clears the virus from the infected host or causes immune-mediated host tissue injury. A complex relationship between viral pathogenesis and host antiviral defense could define the immune ecosystem of virus-infected host tissues. Understanding of the molecular mechanism underlying this ecosystem would uncover strategies to modulate host immune function for antiviral therapeutics. This review presents past and present updates of immune-ecological components of virus infected host tissue and explains how viruses subvert the host immune surveillances.
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Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Viroses/imunologia , Vírus/imunologia , Antivirais/uso terapêutico , Vírus de DNA/genética , Vírus de DNA/imunologia , Humanos , Viroses/virologia , Replicação Viral/imunologia , Vírus/patogenicidadeRESUMO
Influenza A viruses (IAVs) are contagious pathogens responsible for severe respiratory infection in humans and animals worldwide. Upon detection of IAV infection, host immune system aims to defend against and clear the viral infection. Innate immune system is comprised of physical barriers (mucus and collectins), various phagocytic cells, group of cytokines, interferons (IFNs), and IFN-stimulated genes, which provide first line of defense against IAV infection. The adaptive immunity is mediated by B cells and T cells, characterized with antigen-specific memory cells, capturing and neutralizing the pathogen. The humoral immune response functions through hemagglutinin-specific circulating antibodies to neutralize IAV. In addition, antibodies can bind to the surface of infected cells and induce antibody-dependent cell-mediated cytotoxicity or complement activation. Although there are neutralizing antibodies against the virus, cellular immunity also plays a crucial role in the fight against IAVs. On the other hand, IAVs have developed multiple strategies to escape from host immune surveillance for successful replication. In this review, we discuss how immune system, especially innate immune system and critical molecules are involved in the antiviral defense against IAVs. In addition, we highlight how IAVs antagonize different immune responses to achieve a successful infection.
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Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Imunidade Inata , Memória Imunológica , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Humanos , Vigilância Imunológica , Influenza Humana/patologiaRESUMO
Non-coding RNAs (ncRNAs) are a new type of regulators that play important roles in various cellular processes, including cell growth, differentiation, survival, and apoptosis. ncRNAs, including small non-coding RNAs (e.g., microRNAs, small interfering RNAs) and long non-coding RNAs (lncRNAs), are pervasively transcribed in human and mammalian cells. Recently, it has been recognized that these ncRNAs are critically implicated in the virus-host interaction as key regulators of transcription or post-transcription during viral infection. Influenza A virus (IAV) is still a major threat to human health. Hundreds of ncRNAs are differentially expressed in response to infection with IAV, such as infection by pandemic H1N1 and highly pathogenic avian strains. There is increasing evidence demonstrating functional involvement of these regulatory microRNAs, vault RNAs (vtRNAs) and lncRNAs in pathogenesis of influenza virus, including a variety of host immune responses. For example, it has been shown that ncRNAs regulate activation of pattern recognition receptor (PRR)-associated signaling and transcription factors (nuclear factor κ-light-chain-enhancer of activated B cells, NF-κB), as well as production of interferons (IFNs) and cytokines, and expression of critical IFN-stimulated genes (ISGs). The vital functions of IAV-regulated ncRNAs either to against defend viral invasion or to promote progeny viron production are summarized in this review. In addition, we also highlight the potentials of ncRNAs as therapeutic targets and diagnostic biomarkers.
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Interações Hospedeiro-Patógeno , Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/genética , RNA não Traduzido/genética , Animais , Humanos , Imunidade Inata , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: High-frequency deep brain stimulation (DBS) with a single electrical source is effective for motor symptom relief in patients with Parkinson's disease. We postulated that a multiple-source, constant-current device that permits well defined distribution of current would lead to motor improvement in patients with Parkinson's disease. METHODS: We did a prospective, multicentre, non-randomised, open-label intervention study of an implantable DBS device (the VANTAGE study) at six specialist DBS centres at universities in six European countries. Patients were judged eligible if they were aged 21-75 years, had been diagnosed with bilateral idiopathic Parkinson's disease with motor symptoms for more than 5 years, had a Hoehn and Yahr score of 2 or greater, and had a Unified Parkinson's disease rating scale part III (UPDRS III) score in the medication-off state of more than 30, which improved by 33% or more after a levodopa challenge. Participants underwent bilateral implantation in the subthalamic nucleus of a multiple-source, constant-current, eight-contact, rechargeable DBS system, and were assessed 12, 26, and 52 weeks after implantation. The primary endpoint was the mean change in UPDRS III scores (assessed by site investigators who were aware of the treatment assignment) from baseline (medication-off state) to 26 weeks after first lead implantation (stimulation-on, medication-off state). This study is registered with ClinicalTrials.gov, number NCT01221948. FINDINGS: Of 53 patients enrolled in the study, 40 received a bilateral implant in the subthalamic nucleus and their data contributed to the primary endpoint analysis. Improvement was noted in the UPDRS III motor score 6 months after first lead implantation (mean 13·5 [SD 6·8], 95% CI 11·3-15·7) compared with baseline (37·4 [8·9], 34·5-40·2), with a mean difference of 23·8 (SD 10·6; 95% CI 20·3-27·3; p<0·0001). One patient died of pneumonia 24 weeks after implantation, which was judged to be unrelated to the procedure. 125 adverse events were reported, the most frequent of which were dystonia, speech disorder, and apathy. 18 serious adverse events were recorded, three of which were attributed to the device or procedure (one case each of infection, migration, and respiratory depression). All serious adverse events resolved without residual effects and stimulation remained on during the study. INTERPRETATION: The multiple-source, constant-current, eight-contact DBS system suppressed motor symptoms effectively in patients with Parkinson's disease, with an acceptable safety profile. Future trials are needed to investigate systematically the potential benefits of this system on postoperative outcome and its side-effects. FUNDING: Boston Scientific.
Assuntos
Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: International recommendations of the exploration of non-insulin-dependent diabetes mellitus (NIDDM) are focused on deficiency and not incapacity. AIMS: (1) To estimate the incapacity of NIDDM patients through the 6-minute walk test (6MWT) data. (2) To determine their 6-minute walk distance (6MWD) influencing factors (3) To compare data of NIDDM patient group (PG; n = 100) with those of two control groups (CG): CG1 (n = 174, healthy nonobese and nonsmoker); CG2 (n = 55, obese nondiabetic free from comorbidities). POPULATION AND METHODS: The anthropometric, socioeconomic, clinical, metabolic, and 6MWT data of 100 NIDDM patients (45 females) were collected. RESULTS: Total sample means ± standard deviation of age, weight, and height were 54 ± 8 years, 81 ± 14 kg, and 1.64 ± 0.09 m. (1) Measured 6MWD (566 ± 81 m) was significantly lower than the theoretical 6MWD (90% ± 12%). The profile of the PG carrying the 6MWT, was as follows: 23% had an abnormal 6MWD; at the end of the 6MWT, 21% and 12% had, respectively, a low heart rate and a high dyspnea (>5/10), and 4% had desaturation during the walk. The estimated "cardiorespiratory and muscular chain" age (68 ± 16 years) was significantly higher than the chronological age. (2) The factors that significantly influenced the 6MWD (r(2) = 0.58) are included in the following equation: 6MWD (m) = -73.94 × gender (0, male; 1, female) - 3.25 × age (years) + 7.33 × leisure activity score - 35.57 × obesity (0, no; 1, yes) + 32.86 × socioeconomic level (0, low; 1, high) - 27.67 × cigarette use (0, no; 1, yes) + 8.89 × resting oxyhemoglobin saturation - 105.48. (3) Compared to the CGs, the PG had a significantly (P < 0.05) lower 6MWD (100%+9% and 100%+8%, respectively, for the CG1 and CG2). CONCLUSION: NIDDM seems to accelerate the decline of the submaximal aerobic capacity evaluated through the 6MWD.