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1.
Clin Exp Rheumatol ; 37 Suppl 118(3): 185-191, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31376268

RESUMO

Type I interferons (IFN) have long been recognised as mediators of innate immune defense mechanisms against viral threats. Robust evidence over the last 15 years revealed their significant role in the pathogenesis of systemic autoimmune diseases, including systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). Despite the progress, methods of detection, initial triggers, biological functions and clinical associations in the setting of autoimmunity remain to be fully clarified. As therapeutic options for SS are currently limited, neutralising specific targets of the type I IFN pathway seems a promising option. In this review we summarise the current evidence regarding the role of type I IFN in SS.


Assuntos
Interferon Tipo I , Síndrome de Sjogren , Humanos , Interferon Tipo I/efeitos adversos , Interferon Tipo I/genética , Interferon Tipo I/fisiologia , Síndrome de Sjogren/etiologia , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/patologia
2.
Vet Microbiol ; 235: 53-62, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282379

RESUMO

Nucleases are ubiquitously recognized as essential proteins in mycoplasmas because these organisms lack most capacities for de novo synthesis of nucleotides. Some of these proteins were proved to be important pathogenic factors during the infection of mycoplasms. In this study, the protein Mhp597 from M. hyopneumoniae was expressed and purified in Escherichia coli. Analysis of nuclease activity showed that recombinant Mhp597 (rMhp597) was a Ca2+ or Mg2+ dependent thermostable nuclease with very high activity and neutrophil extracellular traps (NETs) induced by M. hyopneumoniae were completely degraded by this nuclease. In addition, when PK15 cells were incubated with different concentrations of rMhp597, their viability was reduced and cell apoptosis was observed in a dose-dependent manner. To further investigate the host immune system response, we report that rMhp597 up-regulated the exression of inflammatory genes showing that TLR4/MyD88/NF-κB signal pathway was involved. On the other hand, rMhp597 down-regulated the expression of type I IFN (IFN-α/ß) and promoted the multiplication of porcine reproductive and respiratory syndrome virus (PRRSV). Recombinant rMhp597δ315-377 lacking C-terminal 63 amino acids exhibited all biological functions mentioned above except for nuclease activity. In summary, Mhp597 is a dynamic secreted nuclease involved in cytotoxicity, inflammation and immunosuppression.


Assuntos
Proteínas de Bactérias/imunologia , Inflamação/genética , Nuclease do Micrococo/imunologia , Mycoplasma hyopneumoniae/enzimologia , Mycoplasma hyopneumoniae/imunologia , Animais , Apoptose , Proteínas de Bactérias/genética , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/genética , Interferon Tipo I/genética , Nuclease do Micrococo/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Transdução de Sinais , Suínos , Replicação Viral
3.
Nat Commun ; 10(1): 2887, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253760

RESUMO

Understanding how immune challenges elicit different responses is critical for diagnosing and deciphering immune regulation. Using a modular strategy to interpret the complex transcriptional host response in mouse models of infection and inflammation, we show a breadth of immune responses in the lung. Lung immune signatures are dominated by either IFN-γ and IFN-inducible, IL-17-induced neutrophil- or allergy-associated gene expression. Type I IFN and IFN-γ-inducible, but not IL-17- or allergy-associated signatures, are preserved in the blood. While IL-17-associated genes identified in lung are detected in blood, the allergy signature is only detectable in blood CD4+ effector cells. Type I IFN-inducible genes are abrogated in the absence of IFN-γ signaling and decrease in the absence of IFNAR signaling, both independently contributing to the regulation of granulocyte responses and pathology during Toxoplasma gondii infection. Our framework provides an ideal tool for comparative analyses of transcriptional signatures contributing to protection or pathogenesis in disease.


Assuntos
Candidíase/metabolismo , Interferon Tipo I/metabolismo , Interferon gama/metabolismo , Melioidose/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções por Vírus Respiratório Sincicial/metabolismo , Animais , Burkholderia pseudomallei , Candida albicans , Candidíase/imunologia , Candidíase/microbiologia , Regulação da Expressão Gênica/imunologia , Vírus da Influenza A Subtipo H3N2 , Interferon Tipo I/sangue , Interferon Tipo I/genética , Interferon gama/sangue , Interferon gama/genética , Pulmão , Melioidose/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Receptor de Interferon alfa e beta , Receptores de Interferon , Infecções por Vírus Respiratório Sincicial/imunologia
4.
J Microbiol Biotechnol ; 29(7): 1137-1143, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216792

RESUMO

Hepatitis E virus (HEV) accounts for 20 million infections in humans worldwide. In most cases, the infections are self-limiting while HEV genotype 1 infection cases may lead to lethal infections in pregnant women (~ 20% fatality). The lack of small animal models has hampered detailed analysis of virus-host interactions and HEV-induced pathology. Here, by employing a recently developed culture-adapted HEV, we demonstrated that methyltransferase, a nonstructural protein, strongly inhibits melanoma differentiation-associated gene 5 (MDA5)- mediated activation of type I interferon responses. Compared to uninfected controls, HEVinfected cells display significantly lower levels of IFN-ß promoter activation when assessed by luciferase assay and RT-PCR. HEV genome-wide screening showed that HEV-encoded methyltransferase (MeT) strongly inhibits MDA5-mediated transcriptional activation of IFN-ß and NF-κB in a dose-responsive manner whether or not it is expressed in the presence/ absence of a tag fused to it. Taken together, current studies clearly demonstrated that HEV MeT is a novel antagonist of MDA5-mediated induction of IFN-ß signaling.


Assuntos
Vírus da Hepatite E/fisiologia , Hepatite E/metabolismo , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Metiltransferases/metabolismo , Proteínas Virais/metabolismo , Células A549 , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Interferon Tipo I/genética , Interferon beta/genética , Interferon beta/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais , Transcrição Genética
5.
Vet Immunol Immunopathol ; 212: 15-22, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213247

RESUMO

Marek's disease virus (MDV), an α-herpesvirus targeting avian species, causes fatal Marek's disease (MD) in chickens. The host interferon (IFN) responses play a key role in resisting viral infection. However, host IFN responses following MDV infection in the chicken central immune organs (thymus and bursa of Fabricius), which contain numerous MDV target cells, is poorly understood. In this study, we performed animal experiments in specific pathogen-free chickens infected with two virulent MDV strains (BS/15 and Md5) or without infection as negative controls. Specifically, the type I IFN (IFN-α and IFN-ß) transcriptional and proteomic expression levels at 7, 10, 14, 17, and 21 days post infection (dpi) were detected and analyzed. Our results indicated that the mRNA and protein expression levels of IFN-α and IFN-ß in the thymus and bursa of Fabricius were mainly downregulated in cytolytic infection (such as 10 dpi) and reactivation (such as 17 dpi) stages, but not the latent (such as 14 dpi) stage of MDV infection, which was determined by comprehensively analyzing the MDV viral load and immune organ damage caused by MDV infection. These data suggest that MDV could inhibit the expression of host type I IFNs, which may be involved in the MDV-induced host immunosuppression and contribute to the immune escape of MDV from host immunity. Furthermore, we found that the downregulated expression of the host type I IFNs induced by BS/15 and Md5 infection was significantly different, which we speculated may be related to the diverse virulence and pathogenicity of MDV strains. In conclusion, our study demonstrated that MDV mostly inhibited the expression of type I IFNs in infected hosts, which may be associated to its pathogenesis.


Assuntos
Interferon Tipo I/imunologia , Doença de Marek/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Bolsa de Fabricius/imunologia , Galinhas , Expressão Gênica , Herpesvirus Galináceo 2 , Interferon Tipo I/genética , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/genética , Interferon beta/imunologia , Doenças das Aves Domésticas/virologia , Proteômica , RNA Mensageiro/genética , Organismos Livres de Patógenos Específicos , Timo/imunologia , Carga Viral , Virulência
6.
Fish Shellfish Immunol ; 91: 78-86, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31039439

RESUMO

Type I interferons, as a class of multipotent cytokines, play a key role in host antiviral immune responses. In this study, a type I IFN coding gene of gibel carp, Carassius auratus gibelio, CagIFNa was cloned and sequenced. The full-length cDNA sequence of CagIFNa consists of 724 nucleotides that encode a predicted protein of 183 amino acids. CagIFNa has two highly conserved cysteine residues in the deduced protein, which is mostly conserved in the fish group I type I IFNs. CagIFNa was identified as a member of the IFNa subgroup of group I type I IFNs by phylogenetic analysis. CagIFNa transcripts were detected in all investigated tissues with higher levels in the liver, intestine, spleen and head kidney of gibel carp. Following injection with Cyprinid herpesvirus 2 (CyHV-2), CagIFNa gene expression was significantly inhibited in the spleen but delayed and then increased in head kidneys. Similarly, while CagIFNa expression was rapidly induced in gibel carp brain (GiCB) cells by poly I:C stimulation and its high induction level was delayed following CyHV-2 infection. CagIFNa overexpression in GiCB cells drastically reduced virus CPE and titer. Furthermore, several genes associated with type I IFN signaling pathway including IRF3, IRF7, IRF9, STAT1, Mx1 and PKR were induced in GiCB cells overexpressing CagIFNa upon CyHV-2 infection. These results show that CagIFNa plays a role in antiviral immune system in gibel carp.


Assuntos
Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Carpa Dourada/genética , Carpa Dourada/imunologia , Imunidade Inata/genética , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Herpesviridae , Infecções por Herpesviridae/imunologia , Interferon Tipo I/química , Filogenia , Poli I-C/farmacologia , Distribuição Aleatória , Alinhamento de Sequência/veterinária
7.
Microb Pathog ; 132: 162-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31054871

RESUMO

Head and neck cancers (HNCs) are a major health problem and a leading cause of morbidity and mortality worldwide. More than 90% of these tumours are head and neck squamous cell carcinomas (HNSCCs). Amongst the common risk factors for HNCs (tobacco and alcohol use), there is a strong association of human papillomavirus (HPV) with HNSCCs. HPV type 16 (HPV 16), the major high-risk HPV type, is most commonly associated with HPV-driven HNSCCs. The promiscuous nature of the major HPV oncogene, E7, allows its interaction with a myriad of host proteins including STING, a component of the viral DNA-sensing cyclic GMP-AMP synthase (cGAS) - stimulator of interferon genes (STING) machinery. Sensing of viral DNA by the cGAS-STING machinery results in a type I interferon (IFN)-mediated anti-viral response. Amelioration of IFN responses resulting from the direct blockade of STING by E7 was first demonstrated in high-risk HPV type 18 (HPV 18) positive (+) cervical squamous cell carcinoma (CESC) cells. However, the role of E7 from HPV 16 (HPV 16E7) in antagonising cGAS-STING responses have not been investigated, let alone in the context of HNSCCs. Here, we show that HPV 16E7+, but not HPV 16E7 negative (-), HNSCC cells respond poorly to cGAS-STING activation stimulus. We further confirm that this inhibition occurred via the highly conserved LXCXE motif in 16E7. This finding contributes to the better understanding of role of high-risk HPV E7 in blocking cGAS-STING pathway, especially in the context of HNSCCs.


Assuntos
DNA Viral/isolamento & purificação , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/genética , Nucleotidiltransferases/genética , Infecções por Papillomavirus/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Linhagem Celular Tumoral , DNA Viral/genética , Regulação Viral da Expressão Gênica , Neoplasias de Cabeça e Pescoço/complicações , Papillomavirus Humano 16/metabolismo , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações
8.
Nat Microbiol ; 4(6): 914-924, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30936491

RESUMO

Interferon (IFN)-mediated antiviral responses are central to host defence against viral infection. Despite the existence of at least 20 IFNs, there are only three known cell surface receptors. IFN signalling and viral evasion mechanisms form an immensely complex network that differs across species. In this Review, we begin by highlighting some of the advances that have been made towards understanding the complexity of differential IFN signalling inputs and outputs that contribute to antiviral defences. Next, we explore some of the ways viruses can interfere with, or circumvent, these defences. Lastly, we address the largely under-reviewed impact of IFN signalling on host tropism, and we offer perspectives on the future of research into IFN signalling complexity and viral evasion across species.


Assuntos
Evasão da Resposta Imune/imunologia , Interferon Tipo I/imunologia , Interferons/imunologia , Transdução de Sinais/imunologia , Viroses/imunologia , Animais , Antivirais , Regulação da Expressão Gênica/imunologia , Regulação da Expressão Gênica/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Evasão da Resposta Imune/fisiologia , Imunidade Inata/imunologia , Imunidade Inata/fisiologia , Interferon Tipo I/genética , Interferon Tipo I/fisiologia , Interferons/genética , Interferons/fisiologia , Transdução de Sinais/fisiologia , Tropismo , Vírus/imunologia
9.
Viral Immunol ; 32(3): 131-143, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30822217

RESUMO

Influenza A viruses (IAVs) have multiple mechanisms for altering the host immune response to aid in virus survival and propagation. While both type I and II interferons (IFNs) have been associated with increased bacterial superinfection (BSI) susceptibility, we found that in some cases type I IFNs can be beneficial for BSI outcome. Specifically, we have shown that antagonism of the type I IFN response during infection by some IAVs can lead to the development of deadly BSI. The nonstructural protein 1 (NS1) from IAV is well known for manipulating host type I IFN responses, but the viral proteins mediating BSI severity remain unknown. In this study, we demonstrate that the PDZ-binding motif (PDZ-bm) of the NS1 C-terminal region from mouse-adapted A/Puerto Rico/8/34-H1N1 (PR8) IAV dictates BSI susceptibility through regulation of IFN-α/ß production. Deletion of the NS1 PDZ-bm from PR8 IAV (PR8-TRUNC) resulted in 100% survival and decreased bacterial burden in superinfected mice compared with 0% survival in mice superinfected after PR8 infection. This reduction in BSI susceptibility after infection with PR8-TRUNC was due to the presence of IFN-ß, as protection from BSI was lost in Ifn-ß-/- mice, resembling BSI during PR8 infection. PDZ-bm in PR8-infected mice inhibited the production of IFN-ß posttranscriptionally, and both delayed and reduced expression of the tunable interferon-stimulated genes. Finally, a similar lack of BSI susceptibility, due to the presence of IFN-ß on day 7 post-IAV infection, was also observed after infection of mice with A/TX98-H3N2 virus that naturally lacks a PDZ-bm in NS1, indicating that this mechanism of BSI regulation by NS1 PDZ-bm may not be restricted to PR8 IAV. These results demonstrate that the NS1 C-terminal PDZ-bm, like the one present in PR8 IAV, is involved in controlling susceptibility to BSI through the regulation of IFN-ß, providing new mechanisms for NS1-mediated manipulation of host immunity and BSI severity.


Assuntos
Infecções por Orthomyxoviridae/veterinária , Domínios PDZ/genética , Superinfecção/microbiologia , Proteínas não Estruturais Virais/genética , Animais , Cães , Regulação da Expressão Gênica , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/imunologia , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Interferon beta/genética , Interferon beta/imunologia , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/virologia , Replicação Viral
10.
Fish Shellfish Immunol ; 87: 809-819, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30776543

RESUMO

Carp from breeding strains with different genetic background present diverse levels of resistance to viral pathogens. Carp strains of Asian origin, currently being treated as Cyprinus rubrofuscus L., especially Amur wild carp (AS), were proven to be more resistant to koi herpesvirus disease (KHVD; caused by cyprinid herpesvirus 3, CyHV-3) than strains originating from Europe and belonging to Cyprinus carpio L., like the Prerov scale carp (PS) or koi carp from a breed in the Czech Republic. We hypothesised that it can be associated with a higher magnitude of type I interferon (IFN) response as a first line of innate defence mechanisms against viral infections. To evaluate this hypothesis, four strains of common carp (AS, Rop, PS and koi) were challenged using two viral infection models: Rhabdovirus SVCV (spring viremia of carp virus) and alloherpesvirus CyHV-3. The infection with SVCV induced a low mortality rates and the most resistant was the Rop strain (no mortalities), whereas the PS strain was the most susceptible (survival rate of 78%). During CyHV-3 infection, Rop and AS strains performed better (survival rates of 78% and 53%, respectively) than PS and koi strains (survival rates of 35% and 10%, respectively). The evaluation of virus loads and virus replication showed significant differences between the carp strains, which correlated with the mortality rate. The evaluation of type I IFN responses showed that there were fundamental differences between the virus infection models. While responses to the SVCV were high, the CyHV-3 generally induced low responses. Furthermore, the results demonstrated that the magnitude of type I IFN responses did not correlate with a higher resistance in infected carp. In the case of a CyHV-3 infection, reduced type I IFN responses could be related to the potential ability of the virus to interfere with cellular sensing of foreign nucleic acids. Taken together, the results broaden our understanding of how common carp from different genetic strains interact with various viral pathogens.


Assuntos
Carpas/genética , Carpas/imunologia , Resistência à Doença/genética , Doenças dos Peixes/imunologia , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Herpesviridae/fisiologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/veterinária , Rhabdoviridae/fisiologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária
11.
Immunity ; 50(1): 51-63.e5, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30635239

RESUMO

Interferon-inducible human oligoadenylate synthetase-like (OASL) and its mouse ortholog, Oasl2, enhance RNA-sensor RIG-I-mediated type I interferon (IFN) induction and inhibit RNA virus replication. Here, we show that OASL and Oasl2 have the opposite effect in the context of DNA virus infection. In Oasl2-/- mice and OASL-deficient human cells, DNA viruses such as vaccinia, herpes simplex, and adenovirus induced increased IFN production, which resulted in reduced virus replication and pathology. Correspondingly, ectopic expression of OASL in human cells inhibited IFN induction through the cGAS-STING DNA-sensing pathway. cGAS was necessary for the reduced DNA virus replication observed in OASL-deficient cells. OASL directly and specifically bound to cGAS independently of double-stranded DNA, resulting in a non-competitive inhibition of the second messenger cyclic GMP-AMP production. Our findings define distinct mechanisms by which OASL differentially regulates host IFN responses during RNA and DNA virus infection and identify OASL as a negative-feedback regulator of cGAS.


Assuntos
2',5'-Oligoadenilato Sintetase/metabolismo , Infecções por Vírus de DNA/imunologia , Vírus de DNA/fisiologia , Infecções por Vírus de RNA/imunologia , Vírus de RNA/imunologia , 2',5'-Oligoadenilato Sintetase/genética , Animais , AMP Cíclico/metabolismo , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotidiltransferases/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Células THP-1 , Replicação Viral
12.
Viruses ; 11(2)2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682859

RESUMO

Proteasome is a large protein complex, which degrades most intracellular proteins. It regulates numerous cellular processes, including the removal of misfolded or unfolded proteins, cell cycle control, and regulation of apoptosis. However, the function of proteasome subunits in viral immunity has not been well characterized. In this study, we identified PSMB1, a member of the proteasome ß subunits (PSMB) family, as a negative regulator of innate immune responses during viral infection. Knockdown of PSMB1 enhanced the RNA virus-induced cytokine and chemokine production. Overexpression of PSMB1 abolished virus-induced activation of the interferon-stimulated response element (ISRE) and interferon beta (IFNß) promoters. Mechanistically, PSMB1 inhibited the activation of RIG-I-like receptor (RLR) and Toll-like receptor 3 (TLR3) signaling pathways. PSMB1 was induced after viral infection and its interaction with IKK-ε promoted degradation of IKK-ε through the ubiquitin-proteasome system. Collectively, our study demonstrates PSMB1 is an important regulator of innate immune signaling.


Assuntos
Regulação da Expressão Gênica/imunologia , Quinase I-kappa B/metabolismo , Imunidade Inata , Complexo de Endopeptidases do Proteassoma/metabolismo , Viroses/imunologia , Linhagem Celular , Quimiocinas/imunologia , Citocinas/imunologia , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/genética , Técnicas de Silenciamento de Genes , Humanos , Quinase I-kappa B/genética , Interferon Tipo I/genética , Interferon beta/antagonistas & inibidores , Complexo de Endopeptidases do Proteassoma/genética , Transdução de Sinais/imunologia , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Replicação Viral
13.
Nat Immunol ; 20(2): 173-182, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30559377

RESUMO

N6-methyladenosine (m6A) is the most common mRNA modification. Recent studies have revealed that depletion of m6A machinery leads to alterations in the propagation of diverse viruses. These effects were proposed to be mediated through dysregulated methylation of viral RNA. Here we show that following viral infection or stimulation of cells with an inactivated virus, deletion of the m6A 'writer' METTL3 or 'reader' YTHDF2 led to an increase in the induction of interferon-stimulated genes. Consequently, propagation of different viruses was suppressed in an interferon-signaling-dependent manner. Significantly, the mRNA of IFNB, the gene encoding the main cytokine that drives the type I interferon response, was m6A modified and was stabilized following repression of METTL3 or YTHDF2. Furthermore, we show that m6A-mediated regulation of interferon genes was conserved in mice. Together, our findings uncover the role m6A serves as a negative regulator of interferon response by dictating the fast turnover of interferon mRNAs and consequently facilitating viral propagation.


Assuntos
Adenosina/análogos & derivados , Interações Hospedeiro-Patógeno/genética , Imunidade Inata/genética , Interferon Tipo I/genética , RNA Mensageiro/metabolismo , Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Citomegalovirus/imunologia , Modelos Animais de Doenças , Feminino , Fibroblastos , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Interferon Tipo I/imunologia , Masculino , Metilação , Metiltransferases/genética , Metiltransferases/imunologia , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Muromegalovirus/imunologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/imunologia , Proteínas de Ligação a RNA/metabolismo
14.
Dev Comp Immunol ; 91: 62-71, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30240715

RESUMO

Type I IFNs are a family of cytokines with antiviral, anti-proliferative and immune-modulatory functions. In this study, four type I IFNs (termed AjIFN1-4) have been cloned from the Japanese eel, Anguilla japonica. The open reading frames of AjIFN1-4 are 552, 534, 546 and 561 bp in length, encoding 183, 177, 181, and 186 amino acids (aa), respectively. Sequence comparison and phylogenetic analysis results revealed that AjIFN1 and AjIFN2 belong to group one (2C-containing) IFNs, while AjIFN3 and AjIFN4 belong to group two (4C-containing) IFNs. Syntenic comparison showed that chromosome block duplication and rearrangement events might have occurred at IFN loci in different teleost lineages. Expression analysis revealed the rapid induction of AjIFNl and AjIFN2 in response to poly I:C stimulation, while AjIFN3 and AjIFN4 were predominantly expressed at later time points. Two Mx promoter reporter assays were conducted to assess the Mx-inducing capability of AjIFN1-4. It is shown that the overexpression of AjIFN1-4 all promoted the luciferase activity of MxB reporter, but the activity of MxC reporter increased only in cells transfected with AjIFN1. Collectively, it is suggested that teleost IFNs were evolved independently in different lineages of fish and may function differently in teleost antiviral immunity.


Assuntos
Anguilla/imunologia , Proteínas de Peixes/genética , Interferon Tipo I/genética , Animais , Células Cultivadas , Clonagem Molecular , Evolução Molecular , Proteínas de Peixes/metabolismo , Expressão Gênica , Imunidade Inata , Interferon Tipo I/metabolismo , Filogenia , Poli I-C/imunologia , Viroses
15.
J Immunol ; 201(12): 3479-3485, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30530500

RESUMO

Type I IFNs (IFN-Is) are powerful cytokines. They provide remarkable protection against viral infections, but their indiscriminate production causes severe self-inflicted damage that can be lethal, particularly in early development. In humans, inappropriately high IFN-I levels caused by defects in the regulatory mechanisms that control IFN-I production and response result in clinical conditions known as type I interferonopathies. In essence, type I interferonopathies define the upper limit of safe, IFN-related inflammation in vivo. Conversely, the loss of IFN-I responsiveness increases susceptibility to viral infections, but, surprisingly, most affected individuals survive despite these inborn errors of immunity. These findings suggest that too much IFN-I early in life is toxic, but that insensitivity to IFN-I is perhaps not the death sentence it was initially thought to be. Human genetic analyses have suggested that seemingly insignificant levels of IFN-regulated gene activity may be sufficient for most of the antiviral defenses used by humans in natura.


Assuntos
Antivirais/uso terapêutico , Imunoterapia/métodos , Inflamação/imunologia , Interferon Tipo I/genética , Viroses/imunologia , Animais , Regulação da Expressão Gênica , Humanos , Imunidade , Inflamação/terapia , Interferon Tipo I/metabolismo , Interferon Tipo I/uso terapêutico , Transdução de Sinais , Viroses/terapia
16.
Medicine (Baltimore) ; 97(52): e13893, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30593198

RESUMO

Tetraparesis is usually due to cerebral palsy (CP), inborn errors of metabolism, neurogenetic disorders and spinal cord lesions. However, literature data reported that about 10% of children with tetraparesis show a negative/non-specific neuroradiological findings without a specific etiological cause. Aicardi Goutières Syndrome (AGS) is a genetic encephalopathy that may cause tetraparesis. Interferon signature is a reliable biomarker for AGS and could be performed in sine-causa tetraparesis. The aim of the study was to examine the type I interferon signature and AGS related-genes in children with sine causa tetraparesis, to look for misdiagnosed AGS. A secondary aim was to determine which aspects of the patient history, clinical picture and brain imaging best characterize tetraparesis due to an interferonopathy.Seven out of 78 patients affected by tetraparesis, characterized by unremarkable pre-peri-postnatal history and normal/non-specific brain magnetic resonance imaging (MRI) were selected and underwent anamnestic data collection, clinical examination, brain imaging review, peripheral blood interferon signature and AGS-related genes analysis.At our evaluation time (mean age of 11.9 years), all the 7 patients showed spastic-dystonic tetraparesis. At clinical onset brain MRI was normal in 4 and with non-specific abnormalities in 3; at follow-up 3 patients presented with new white-matter lesions, associated with brain calcification in 1 case. Interferon signature was elevated in one subject who presented also a mutation of the IFIH1 gene.AGS should be considered in sine-causa tetraparesis. Core features of interferonopathy-related tetraparesis are: onset during first year of life, psychomotor regression with tetraparesis evolution, brain white-matter lesions with late calcifications. A positive interferon signature may be a helpful marker to select patients with spastic tetraparesis who should undergo genetic analysis for AGS.


Assuntos
Doenças Autoimunes do Sistema Nervoso/complicações , Doenças Autoimunes do Sistema Nervoso/diagnóstico , Interferon Tipo I/biossíntese , Malformações do Sistema Nervoso/complicações , Malformações do Sistema Nervoso/diagnóstico , Paresia/etiologia , Adolescente , Doenças Autoimunes do Sistema Nervoso/diagnóstico por imagem , Doenças Autoimunes do Sistema Nervoso/genética , Biomarcadores , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Interferon Tipo I/sangue , Interferon Tipo I/genética , Imagem por Ressonância Magnética , Masculino , Malformações do Sistema Nervoso/diagnóstico por imagem , Malformações do Sistema Nervoso/genética , Projetos Piloto , Adulto Jovem
17.
Theriogenology ; 120: 61-67, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30096617

RESUMO

The embryonic mortality in cows is a growing concern for an ever-expanding dairy industry. The current study was an attempt to shorten the open period of dairy cows having suffered embryonic loss by diagnosing them at an earlier stage. The blood samples were collected from the Karan Fries (KF) cows on days 0 (day of AI/estrus), 4, 8, 12, 14, 16, 18, 21, 24, 28, 35 and 42 post insemination. The experimental animals were then categorized into pregnant (P), conception failure/early embryonic mortality (EEM) and late embryonic mortality cows (LEM), based on progesterone assay, ultrasonography and per-rectal palpation. There were 6 animals in each group. The plasma progesterone was higher in pregnant than EEM and LEM cows. Plasma Interferon-tau concentration was significantly (p < 0.05) lower in LEM than pregnant cows where it could be detected from day 14-21 but was non-detectable in EEM cows. The mRNA expression of ISG15, OAS1, MX1 and MX2 in blood neutrophils was significantly (p < 0.05) higher from day 8-42 as against day 0 in pregnant cows. The highest expression was observed around day 18-21 in pregnant cows. The ISG15, OAS1, MX1 and MX2 mRNA expression was significantly (p < 0.05) higher from day 4-42 as compared to day 0 in LEM cows, whereas in EEM cows the expression stayed close to that of day 0 (1.00 ±â€¯0.00). The mRNA expression of ISG15, OAS1, MX1 and MX2 started to decline from day 24 onwards. The degree of expression of Interferon-tau stimulated genes was higher in pregnant and LEM cows than EEM cows. The study reveals that the Interferon tau stimulated gene expression in neutrophils can act as peripheral biomarkers for detecting the embryonic mortality in dairy cows.


Assuntos
Bovinos/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Interferon Tipo I/fisiologia , Proteínas da Gravidez/fisiologia , 2',5'-Oligoadenilato Sintetase/genética , 2',5'-Oligoadenilato Sintetase/metabolismo , Animais , Biomarcadores/metabolismo , Bovinos/genética , Bovinos/metabolismo , Citocinas/genética , Citocinas/metabolismo , Feminino , Interferon Tipo I/sangue , Interferon Tipo I/genética , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Gravidez , Proteínas da Gravidez/sangue , Proteínas da Gravidez/genética , Progesterona/sangue , RNA Mensageiro/metabolismo
18.
Proc Natl Acad Sci U S A ; 115(33): E7814-E7823, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30061383

RESUMO

Understanding of T cell exhaustion and successful therapy to restore T cell function was first described using Clone (Cl) 13 variant selected from the lymphocytic choriomeningitis virus (LCMV) Armstrong (ARM) 53b parental strain. T cell exhaustion plays a pivotal role in both persistent infections and cancers of mice and humans. C57BL/6, BALB, SWR/J, A/J, 129, C3H, and all but one collaborative cross (CC) mouse strain following Cl 13 infection have immunosuppressed T cell responses, high PD-1, and viral titers leading to persistent infection and normal life spans. In contrast, the profile of FVB/N, NZB, PL/J, SL/J, and CC NZO mice challenged with Cl 13 is a robust T cell response, high titers of virus, PD-1, and Lag3 markers on T cells. These mice all die 7 to 9 d after Cl 13 infection. Death is due to enhanced pulmonary endothelial vascular permeability, pulmonary edema, collapse of alveolar air spaces, and respiratory failure. Pathogenesis involves abundant levels of Cl 13 receptor alpha-dystroglycan on endothelial cells, with high viral replication in such cells leading to immunopathologic injury. Death is aborted by blockade of interferon-1 (IFN-1) signaling or deletion of CD8 T cells.


Assuntos
Linfócitos T CD8-Positivos , Interferon Tipo I , Coriomeningite Linfocítica , Vírus da Coriomeningite Linfocítica/fisiologia , Replicação Viral/genética , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/metabolismo , Coriomeningite Linfocítica/patologia , Camundongos , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo
19.
Proc Natl Acad Sci U S A ; 115(33): E7768-E7775, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30061387

RESUMO

The adaptor molecule stimulator of IFN genes (STING) is central to production of type I IFNs in response to infection with DNA viruses and to presence of host DNA in the cytosol. Excessive release of type I IFNs through STING-dependent mechanisms has emerged as a central driver of several interferonopathies, including systemic lupus erythematosus (SLE), Aicardi-Goutières syndrome (AGS), and stimulator of IFN genes-associated vasculopathy with onset in infancy (SAVI). The involvement of STING in these diseases points to an unmet need for the development of agents that inhibit STING signaling. Here, we report that endogenously formed nitro-fatty acids can covalently modify STING by nitro-alkylation. These nitro-alkylations inhibit STING palmitoylation, STING signaling, and subsequently, the release of type I IFN in both human and murine cells. Furthermore, treatment with nitro-fatty acids was sufficient to inhibit production of type I IFN in fibroblasts derived from SAVI patients with a gain-of-function mutation in STING. In conclusion, we have identified nitro-fatty acids as endogenously formed inhibitors of STING signaling and propose for these lipids to be considered in the treatment of STING-dependent inflammatory diseases.


Assuntos
Ácidos Graxos/metabolismo , Herpes Simples/metabolismo , Herpesvirus Humano 2/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Animais , Doenças Autoimunes do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/metabolismo , Doenças Autoimunes do Sistema Nervoso/patologia , Herpes Simples/genética , Herpes Simples/patologia , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Lipoilação , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/metabolismo , Malformações do Sistema Nervoso/patologia , Células RAW 264.7
20.
Microbiol Immunol ; 62(9): 585-593, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30160073

RESUMO

MicroRNAs are short, non-coding RNAs that have been shown to regulate a wide range of biological processes, including host antiviral immune responses. In the present study, microRNA-92a (miR-92a) was identified as a negative regulator in macrophage-mediated antiviral responses. Overexpression of miR-92a decreases vesicular stomatitis virus (VSV)-induced production of type-I IFNs and facilitates viral replication in macrophages. The mechanism is that miR-92a directly targets RIG-I and reduces its expression, thereby attenuating VSV-triggered activation of TBK-binding kinase 1 and IRF3, both of which are crucial for initiating transcription of type-I IFN genes. Our results demonstrate for the first time the novel role of miR-92a in suppressing antiviral innate immunity.


Assuntos
Proteína DEAD-box 58/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Estomatite Vesicular/imunologia , Vírus da Estomatite Vesicular Indiana/imunologia , Animais , Antivirais/metabolismo , Citocinas/metabolismo , Proteína DEAD-box 58/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Células HEK293 , Humanos , Imunidade Inata/imunologia , Fator Regulador 3 de Interferon/imunologia , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células RAW 264.7/efeitos dos fármacos , Alinhamento de Sequência , Regulação para Cima/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
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