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Porcine epidemic diarrhea virus (PEDV) is a major causative pathogen of a highly contagious, acute enteric viral disease. This study evaluated the emergence of nine variants in Jiangsu and Anhui provinces of China from 2020 to 2023. S gene-based phylogenetic analysis indicated that three variants belong to the G1c subgroup, while the other six strains are clustered within the G2c subgroup. Recombination analyses supported that three variants of the G1c subgroup were likely derived from recombination of parental variants FR0012014 and a donor variant AJ1102. In addition, there are novel mutations on amino acid 141-148 and these likely resulted in changes in antigenicity in the three variants. These results illustrated that the study provides novel insights into the epidemiology, evolution, and transmission of PEDV in China.
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Stimulator of IFN genes (STING) is a critical component of the innate immune system, playing an essential role in defending against DNA virus infections. However, the mechanisms governing basal STING regulation remain poorly understood. In this study, we demonstrate that the basal level of STING is critically maintained by hypoxia-inducible factor 1 (HIF-1)α through transcription. Under normal conditions, HIF-1α binds constitutively to the promoter region of STING, actively promoting its transcription. Knocking down HIF-1α results in a decrease in STING expression in multiple cell lines and zebrafish, which in turn reduces cellular responses to synthetic dsDNAs, including cell signaling and IFN production. Moreover, this decrease in STING levels leads to an increase in cellular susceptibility to DNA viruses HSV-1 and pseudorabies virus. These findings unveil a (to our knowledge) novel role of HIF-1α in maintaining basal STING levels and provide valuable insights into STING-mediated antiviral activities and associated diseases.
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Herpesvirus Humano 1 , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imunidade Inata , Proteínas de Membrana , Peixe-Zebra , Animais , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peixe-Zebra/imunologia , Herpesvirus Humano 1/imunologia , Herpesvirus Suídeo 1/imunologia , Imunidade Celular , Regulação da Expressão Gênica/imunologia , Transdução de Sinais/imunologia , Transcrição Gênica/imunologia , Regiões Promotoras Genéticas , Células HEK293 , Linhagem Celular , Herpes Simples/imunologia , Pseudorraiva/imunologiaRESUMO
The UK Biobank (UKB) has the largest adult brain imaging dataset, which encompasses over 40,000 participants. A significant number of Mendelian randomization (MR) studies based on UKB neuroimaging data have been published to validate potential causal relationships identified in observational studies. Relevant articles published before December 2023 were identified following the PRISMA protocol. Included studies (n = 34) revealed that there were causal relationships between various lifestyles, diseases, biomarkers, and brain image-derived phenotypes (BIDPs). In terms of lifestyle habits and environmental factors, there were causal relationships between alcohol consumption, tea intake, coffee consumption, smoking, educational attainment, and certain BIDPs. Additionally, some BIDPs could serve as mediators between leisure/physical inactivity and major depressive disorder. Regarding diseases, BIDPs have been found to have causal relationships not only with Alzheimer's disease, stroke, psychiatric disorders, and migraine, but also with cardiovascular diseases, diabetes, poor oral health, osteoporosis, and ankle sprain. In addition, there were causal relationships between certain biological markers and BIDPs, such as blood pressure, LDL-C, IL-6, telomere length, and more.
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Pathogenic microorganism of silkworm are important factors that threaten the high-quality development of sericulture. Among them, Bombyx mori nucleopolyhedrovirus (BmNPV) caused diseases often lead to frequent outbreaks and high mortality, resulting in huge losses to sericultural industry. Current molecular detection methods for BmNPV require expensive equipment and sikilled technical personnel. As a result, the most commonly detection method for silkworm egg production enterprises involves observing the presence of polyhedra under a microscope. However, this method has low accuracy and sensitivity. There is an urgent need to develop a new detection technology with high sensitivity, high specificity, and applicability for silkworm farms, silkworm egg production enterprises and quarantine departments. In this study, we successfully established the CRISPR/Cas13a BmNPV visualized detection technology by combining Recombinase Polymerase Amplification (RPA) technology and CRISPR/Cas13a system. This technology is based on microplate lateral, flow test strips and portable fluorescence detector. The detection sensitivity can reach up to 1 copies/µL for positive standard plasmid and 1 fg/µL for BmNPV genome in 30-45 min, demonstrating high sensitivity. By detecting silkworm tissues infected with different pathogens, we determined that CRISPR/Cas13a detection technology has good specificity. In summary, the newly established nucleic acid detection technology for BmNPV is characterized by high sensitivity, high specificity, low cost and convenience for visualization. It can be applied in field detection and silkworm egg quality monitory system.
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Bombyx , Nucleopoliedrovírus , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Nucleopoliedrovírus/genética , Sensibilidade e EspecificidadeRESUMO
Bombyx mori bidensovirus (BmBDV) is one of the most important pathogens of silkworm. It mainly infects midgut cells of silkworm and causes losses to the sericulture industry. Long noncoding RNAs (lncRNAs) have been reported to play an important role in the regulation of antiviral immune response in silkworm. To explore whether lncRNAs are involved in BmBDV infection and immune response of silkworm, we performed a comparative transcriptome analysis to identify the lncRNAs and mRNAs between the BmBDV infected and noninfected silkworm larvae at the early stage. A total of 16,069 genes and 974 candidate lncRNAs were identified, among which 142 messenger RNA (mRNAs) and four lncRNAs were differentially expressed (DE). Target gene prediction revealed that 142 DEmRNAs were coexpressed with four DElncRNAs, suggesting that the expression of mRNA is mainly affected through trans-regulation activities. A regulatory network of DElncRNAs and DEmRNAs was constructed, showing that many genes targeted by different DElncRNAs are involved in metabolism and immunity, which implies that these genes and lncRNAs play an important role in the replication of BmBDV. Our results will help us to improve our understanding of lncRNA-mediated regulatory roles in BmBDV infection, providing a new perspective for further exploring the interaction between host and BmBDV.
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Bombyx , Vírus de Insetos , RNA Longo não Codificante , Animais , RNA Longo não Codificante/genética , Vírus de Insetos/genética , Perfilação da Expressão GênicaRESUMO
Pathogens cause infections and millions of deaths globally, while antipathogens are drugs or treatments designed to combat them. To date, multifunctional nanomaterials (NMs), such as organic, inorganic, and nanocomposites, have attracted significant attention by transforming antipathogen livelihoods. They are very small in size so can quickly pass through the walls of bacterial, fungal, or parasitic cells and viral particles to perform their antipathogenic activity. They are more reactive and have a high band gap, making them more effective than traditional medications. Moreover, due to some pathogen's resistance to currently available medications, the antipathogen performance of NMs is becoming crucial. Additionally, due to their prospective properties and administration methods, NMs are eventually chosen for cutting-edge applications and therapies, including drug administration and diagnostic tools for antipathogens. Herein, NMs have significant characteristics that can facilitate identifying and eliminating pathogens in real-time. This mini-review analyzes multifunctional NMs as antimicrobial tools and investigates their mode of action. We also discussed the challenges that need to be solved for the utilization of NMs as antipathogens.
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Anti-Infecciosos , Nanoestruturas , Humanos , Animais , Gado , Estudos Prospectivos , Anti-Infecciosos/farmacologiaRESUMO
Introduction: Ablation therapy is a commonly used tool in the management of hepatocellular carcinoma (HCC). After ablation, dying cancer cells release a variety of substances that trigger subsequent immune responses. Immunogenic cell death (ICD) has been a trending topic in recent years and has been discussed many times along with oncologic chemotherapy. However, the subject of ablative therapy and ICDs has been little discussed. The purpose of this study was to investigate whether ablation treatment induces ICD in HCC cells and whether different types of ICDs arise because of different ablation temperatures. Methods: Four different HCC cell lines (H22, Hepa-16, HepG2 and SMMC7221) were cultured and treated under different temperatures (-80°C, -40°C, 0°C, 37°C, and 60°C). Cell Counting Kit-8 assay was performed to analyze the viability of different cell lines. Apoptosis was detected by flow cytometry assay, and a few ICD-related cytokines (calreticulin, ATP, high mobility group box 1, and CXCL10) were detected by immunofluorescence or enzyme-linked immunosorbent assay. Results: The apoptosis rate of all kinds of cells increased significantly in -80°C group (p < 0.01) and 60°C group (p < 0.01). The expression levels of ICD-related cytokines were mostly significantly different between the different groups. For calreticulin, Hepa1-6 cells and SMMC7221 cells showed significantly higher protein expression levels in 60°C group (p < 0.01) and significantly lower protein expression levels -80°C group (p < 0.01). The ATP, high mobility group box 1 and CXCL10 expression levels were significantly higher in 60°C, -80°C and -40°C group of all four cell lines (p < 0.01). Conclusion: Different ablative treatments could induce different types of ICDs in HCC cells, providing a promising track for the development of individualized cancer therapies.
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Type I interferon (IFN-I) response plays a prominent role in innate immunity, which is frequently modulated during viral infection. Here, we report DNA methylation regulator UHRF1 as a potent negative regulator of IFN-I induction during alphaherpesvirus infection, whereas the viruses in turn regulates the transcriptional expression of UHRF1. Knockdown of UHRF1 in cells significantly increases interferon-ß (IFN-ß)-mediated gene transcription and viral inhibition against herpes simplex virus 1 (HSV1) and pseudorabies virus (PRV). Mechanistically, UHRF1 deficiency promotes IFN-I production by triggering dsRNA-sensing receptor RIG-I and activating IRF3 phosphorylation. Knockdown of UHRF1 in cells upregulates the accumulation of double-stranded RNA (dsRNA), including host endogenous retroviral sequence (ERV) transcripts, while the treatment of RNase III, known to specifically digest dsRNA, prevents IFN-ß induction by siUHRF1. Furthermore, the double-knockdown assay of UHRF1 and DNA methyltransferase DNMT1 suggests that siUHRF1-mediated DNA demethylation may play an important role in dsRNA accumulation and subsequently IFN induction. These findings establish the essential role of UHRF1 in IFN-I-induced antiviral immunity and reveal UHRF1 as a potential antivrial target. IMPORTANCE Alphaherpesviruses can establish lifelong infections and cause many diseases in humans and animals, which rely partly on their interaction with IFN-mediated innate immune response. Using alphaherpesviruses PRV and HSV-1 as models, we identified an essential role of DNA methylation regulator UHRF1 in IFN-mediated immunity against virus replication, which unravels a novel mechanism employed by epigenetic factor to control IFN-mediated antiviral immune response and highlight UHRF1, which might be a potential target for antiviral drug development.
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Herpesvirus Humano 1 , Herpesvirus Suídeo 1 , Interferon Tipo I , Animais , Humanos , Antivirais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Expressão Gênica , Herpesvirus Humano 1/genética , Herpesvirus Suídeo 1/genética , Imunidade Inata , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Interferon beta/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Alphaherpesvirinae , Receptores Imunológicos/imunologiaRESUMO
HIF-1α plays a crucial part in hypoxia response by transcriptionally upregulating genes to adapt the hypoxic condition. HIF-1α is under severe cellular control as its exceptional activation is always associated with tumorigenesis and tumor progression. Here, we report L3MBTL3 serves as a novel negative regulator of HIF-1α. It is upregulated during hypoxia and acts as a transcriptional target of HIF-1α. In the nuclei, L3MBTL3 makes an interaction with HIF-1α and promotes its ubiquitination and degradation. These findings indicate L3MBTL3 forms a negative feedback loop with HIF-1α in vitro to dampen the hypoxic response.
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Biodegradation of antibiotic pollutants by microorganisms has received widespread attention, to which the identification of microorganisms capable of efficiently degrading antibiotics is a key. In this study, a strain DM-1 with high degradation capability was successfully isolated from monensin-contaminated chicken manure by using monensin as the sole carbon source. The strain was further identified basing on morphological, physiological and biochemical characteristics and 16S rRNA gene sequence-based phylogenetic analysis. The degradation efficiency of DM-1 for monensin was determined by HPLC post-column derivatization, and then the degradation conditions of DM-1 were optimized. DM-1 was identified as a strain of Acinetobacter and named as Acinetobacter baumannii DM-1. The optimal conditions for monensin degradation by strain DM-1 were pH 7.0, 30 â, and initial monensin concentration of 50 mg/L. The strain DM-1 degraded more than 87.51% of monensin at an initial concentration of 10 mg/L in 28 days, while only a slight decrease in monensin concentration was observed in the control without monensin-degrading strain. This study indicates that the strain DM-1 has a promising application prospect in the bioremediation of monensin-contaminated environment.
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Bactérias , Monensin , Bactérias/genética , Biodegradação Ambiental , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do SoloRESUMO
The alphaherpesvirus pseudorabies virus (PRV) is the etiologic agent of swine Aujeszky's disease, which can cause huge economic losses to the pig industry. PRV can overcome a type I interferon (IFN)-induced antiviral state in host cells through its encoded EP0 protein. However, the exact role of EP0 in this process is poorly defined. Here, we report that EP0 transcriptionally represses IFN regulatory factor 9 (IRF9), a critical component in the IFN signaling pathway, thereby reducing the cellular levels of IRF9 and inhibiting IFN-induced gene transcription. This activity of EP0 is mediated by its C-terminal region independently of the RING domain. Moreover, compared with EP0 wild-type PRV, EP0-deficient PRV loses the ability to efficiently decrease cellular IRF9, while reintroducing the C-terminal region of EP0 back into the EP0-deficient virus restores the activity. Together, these results suggest that EP0 can transcriptionally modulate IRF9-mediated antiviral pathways through its C-terminal region, contributing to PRV innate immune evasion. IMPORTANCE Alphaherpesviruses can establish lifelong infections and cause many diseases in humans and animals. Pseudorabies virus (PRV) is a swine alphaherpesvirus that threatens pig production. Using PRV as a model, we found that alphaherpesvirus can utilize its encoded early protein EP0 to inhibit the IFN-induced upregulation of antiviral proteins by reducing the basal expression levels of IRF9 through repressing its transcription. Our findings reveal a mechanism employed by alphaherpesvirus to evade the immune response and indicate that EP0 is an important viral protein in pathogenesis and a potential target for antiviral drug development.
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Herpesvirus Suídeo 1 , Interferon Tipo I , Fator Gênico 3 Estimulado por Interferon, Subunidade gama , Pseudorraiva , Doenças dos Suínos , Animais , Antivirais/farmacologia , Regulação da Expressão Gênica/imunologia , Herpesvirus Suídeo 1/imunologia , Herpesvirus Suídeo 1/metabolismo , Interações entre Hospedeiro e Microrganismos/imunologia , Interferon Tipo I/metabolismo , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Pseudorraiva/imunologia , Pseudorraiva/virologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Proteínas Virais/metabolismoRESUMO
Alphaherpesviruses are large dsDNA viruses with an ability to establish persistent infection in hosts, which rely partly on their ability to evade host innate immune responses, notably the type I IFN response. However, the relevant molecular mechanisms are not well understood. In this study, we report the UL42 proteins of alphaherpesvirus pseudorabies virus (PRV) and HSV type 1 (HSV1) as a potent antagonist of the IFN-I-induced JAK-STAT signaling pathway. We found that ectopic expression of UL42 in porcine macrophage CRL and human HeLa cells significantly suppresses IFN-α-mediated activation of the IFN-stimulated response element (ISRE), leading to a decreased transcription and expression of IFN-stimulated genes (ISGs). Mechanistically, UL42 directly interacts with ISRE and interferes with ISG factor 3 (ISGF3) from binding to ISRE for efficient gene transcription, and four conserved DNA-binding sites of UL42 are required for this interaction. The substitution of these DNA-binding sites with alanines results in reduced ISRE-binding ability of UL42 and impairs for PRV to evade the IFN response. Knockdown of UL42 in PRV remarkably attenuates the antagonism of virus to IFN in porcine kidney PK15 cells. Our results indicate that the UL42 protein of alphaherpesviruses possesses the ability to suppress IFN-I signaling by preventing the association of ISGF3 and ISRE, thereby contributing to immune evasion. This finding reveals UL42 as a potential antiviral target.
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DNA Polimerase Dirigida por DNA/imunologia , Exodesoxirribonucleases/imunologia , Herpesvirus Suídeo 1/imunologia , Interferon Tipo I/imunologia , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/imunologia , Proteínas Virais/imunologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Células HeLa , Herpesvirus Humano 1/imunologia , Humanos , Evasão da Resposta Imune/imunologia , Imunidade Inata/imunologia , Pseudorraiva/imunologia , Elementos de Resposta/imunologia , Transdução de Sinais/imunologia , Suínos , Transcrição Gênica/imunologiaRESUMO
Promyelocytic leukemia nuclear bodies (PML-NBs) possess an important intrinsic antiviral activity against alphaherpesvirus infection. PML is the structural backbone of NBs, comprising different isoforms. However, the contribution of each isoform to alphaherpesvirus restriction is not well understood. Here, we report the role of PML-NBs and swine PML (sPML) isoforms in pseudorabies virus (PRV) infection in its natural host swine cells. We found that sPML-NBs exhibit an anti-PRV activity in the context of increasing the expression level of endogenous sPML. Of four sPML isoforms cloned and examined, only isoforms sPML-II and -IIa, not sPML-I and -IVa, expressed in a sPML knockout cells inhibit PRV infection. Both the unique 7b region of sPML-II and the sumoylation-dependent normal formation of PML-NBs are required. 7b possesses a transcriptional repression activity and suppresses viral gene transcription during PRV infection with the cysteine residues 589 and 599 being critically involved. We conclude that sPML-NBs inhibit PRV infection partly by repressing viral gene transcription through the 7b region of sPML-II.IMPORTANCE PML-NBs are nuclear sites that mediate the antiviral restriction of alphaherpesvirus gene expression and replication. However, the contribution of each PML isoform to this activity of PML-NBs is not well characterized. Using PRV and its natural host swine cells as a system, we have discovered that the unique C terminus of sPML isoform II is required for PML-NBs to inhibit PRV infection by directly engaging in repression of viral gene transcription. Our study not only confirms in swine cells that PML-NBs have an antiviral function but also presents a mechanism to suggest that PML-NBs inhibit viral infection in an isoform specific manner.
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Herpesvirus Suídeo 1/genética , Corpos de Inclusão Intranuclear/genética , Proteína da Leucemia Promielocítica/genética , Transcrição Gênica , Proteínas Virais/genética , Animais , Linhagem Celular , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Regulação da Expressão Gênica , Células HEK293 , Herpesvirus Suídeo 1/metabolismo , Herpesvirus Suídeo 1/patogenicidade , Interações Hospedeiro-Patógeno/genética , Humanos , Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/virologia , Macrófagos/metabolismo , Macrófagos/virologia , Proteína da Leucemia Promielocítica/metabolismo , Domínios Proteicos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade , Sumoilação , Suínos , Proteínas Virais/metabolismoRESUMO
Hypoxic stress is intimately connected with tumor progression, with hypoxia-inducible factor-1α (HIF-1α) being a critical regulator in this process. HIF-1α is stabilized in response to hypoxia, which is required for the induction of gene transcriptions important for hypoxic adaptation. Bclaf1 is a multifunctional protein involved in tumorigenesis, however, its role in this process is not well characterized. Here we report Bclaf1 is a direct transcriptional target of HIF-1 and upregulated in multiple cell lines during hypoxia. Importantly, we found Bclaf1 is involved in the stabilization of HIF-1α during long-term hypoxic treatments. Compared with the control cells, the protein level and stability of HIF-1α in Bclaf1 knockdown or knockout cells is greatly compromised after long-term hypoxic treatments, concomitant with the impaired inductions of HIF-1 target gene transcription. Bclaf1 knockout HeLa cells exhibit a reduced tumor growth in mice xenografts, in which the expressions of HIF-1α and its target genes are also decreased. Bclaf1 binds to HIF-1α in the nucleus, and this interaction is required for Bclaf1 to stabilize HIF-1α in hypoxic condition. These results uncover a positive feedback loop, HIF-1-Bclaf1, that sustains HIF-1 activity during long-term hypoxic conditions by binding to and protecting HIF-1α from degradation, and suggest that Bclaf1 may promote tumor progression by enhancing HIF-1α stability.
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Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/genética , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Hipóxia Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Humanos , Camundongos , Neoplasias/patologia , Estabilidade Proteica , Proteínas Repressoras/genética , Transcrição Gênica , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Type I interferon response plays a prominent role against viral infection, which is frequently disrupted by viruses. Here, we report Bcl-2 associated transcription factor 1 (Bclaf1) is degraded during the alphaherpesvirus Pseudorabies virus (PRV) and Herpes simplex virus type 1 (HSV-1) infections through the viral protein US3. We further reveal that Bclaf1 functions critically in type I interferon signaling. Knockdown or knockout of Bclaf1 in cells significantly impairs interferon-α (IFNα) -mediated gene transcription and viral inhibition against US3 deficient PRV and HSV-1. Mechanistically, Bclaf1 maintains a mechanism allowing STAT1 and STAT2 to be efficiently phosphorylated in response to IFNα, and more importantly, facilitates IFN-stimulated gene factor 3 (ISGF3) binding with IFN-stimulated response elements (ISRE) for efficient gene transcription by directly interacting with ISRE and STAT2. Our studies establish the importance of Bclaf1 in IFNα-induced antiviral immunity and in the control of viral infections.
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Interferons/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Virais/metabolismo , Alphaherpesvirinae/metabolismo , Alphaherpesvirinae/patogenicidade , Animais , Antivirais/farmacologia , Linhagem Celular , China , Herpesvirus Humano 1/metabolismo , Herpesvirus Suídeo 1/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Interferon Tipo I/imunologia , Fator Gênico 3 Estimulado por Interferon, Subunidade alfa/metabolismo , Interferon-alfa/metabolismo , Interferons/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Repressoras/fisiologia , Elementos de Resposta , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais/imunologia , Proteínas Supressoras de Tumor/fisiologia , Proteínas Virais/genética , Viroses/genéticaRESUMO
Alphaherpesviruses that establish persistent infections rely partly on their ability to evade host antiviral responses, notably the type I interferon (IFN) response. However, the mechanisms employed by alphaherpesviruses to avoid this response are not well understood. Pseudorabies virus (PRV) is an economically important pathogen and a useful model system for studying alphaherpesvirus biology. To identify PRV proteins that antagonize type I IFN signaling, we performed a screen by using an IFN-stimulated response element reporter in the swine cell line CRL. Unexpectedly, we identified the dUTPase UL50 as a strong inhibitor. We confirmed that UL50 has the ability to inhibit type I IFN signaling by performing ectopic expression of UL50 in cells and deletion of UL50 in PRV. Mechanistically, UL50 impeded type I IFN-induced STAT1 phosphorylation, likely by accelerating lysosomal degradation of IFN receptor 1 (IFNAR1). In addition, this UL50 activity was independent of its dUTPase activity and required amino acids 225 to 253 in the C-terminal region. The UL50 encoded by herpes simplex virus 1 (HSV-1) also possessed similar activity. Moreover, UL50-deleted PRV was more susceptible to IFN than UL50-proficient PRV. Our results suggest that in addition to its dUTPase activity, the UL50 protein of alphaherpesviruses possesses the ability to suppress type I IFN signaling by promoting lysosomal degradation of IFNAR1, thereby contributing to immune evasion. This finding reveals UL50 as a potential antiviral target.IMPORTANCE Alphaherpesviruses can establish lifelong infections and cause many diseases in humans and animals. Pseudorabies virus (PRV) is a swine alphaherpesvirus that threatens pig production. Using PRV as a model, we found that this alphaherpesvirus could utilize its encoded dUTPase UL50 to induce IFNAR1 degradation and inhibit type I IFN signaling in an enzymatic activity-independent manner. Our finding reveals a mechanism employed by an alphaherpesvirus to evade the immune response and indicates that UL50 is an important viral protein in pathogenesis and is a potential target for antiviral drug development.
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Herpesvirus Suídeo 1/enzimologia , Interferon Tipo I/farmacologia , Lisossomos/metabolismo , Pseudorraiva/metabolismo , Pirofosfatases/metabolismo , Receptor de Interferon alfa e beta/metabolismo , Sequência de Aminoácidos , Animais , Antivirais/farmacologia , Células HeLa , Herpesvirus Suídeo 1/genética , Humanos , Evasão da Resposta Imune , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/virologia , Fosforilação , Proteólise , Pseudorraiva/tratamento farmacológico , Pseudorraiva/virologia , Pirofosfatases/genética , Receptor de Interferon alfa e beta/genética , Homologia de Sequência , Transdução de Sinais , Suínos , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
This study was conducted to clarify the relationships among immunoglobulin (Ig)M, IgG, IgA, ß-carotene, vitamin A and α-tocopherol contents in colostrum of 24 Japanese Black multiparous cows in order to evaluate the role of IgM on colostral IgG and IgA production. Compared with colostral IgG, colostral IgM and IgA were very low but varied widely. There was positive correlation between colostral IgM and IgG, but colostral IgM was not related with colostral IgA. There was no relationship between colostral IgM and age of cows, although colostral IgG was increased with aging. There were positive correlations among colostral ß-carotene, vitamin A and α-tocopherol and these vitamins were positively correlated with colostral IgM and IgG. These results indicate that fat-soluble vitamins may affect colostral IgG and IgM in cows and colostral IgG increases with the increase of colostral IgM.
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Colostro/química , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Envelhecimento/metabolismo , Animais , Bovinos , Feminino , Vitamina A/metabolismo , alfa-Tocoferol/metabolismo , beta Caroteno/metabolismoRESUMO
Data from 19 Japanese Black multiparous cows were collected to clarify the relationships among immunoglobulin (Ig) G, IgA, ß-carotene, vitamin A and α-tocopherol contents in colostrum of cows in order to evaluate the role of fat-soluble vitamins on colostral IgG and IgA production. Mean colostral IgG was 141 mg/mL, ranging from 65 to 208 mg/mL, whereas mean colostral IgA was 8.7 mg/mL, ranging from 1.0 to 34.6 mg/mL. Colostral IgG increased with aging in multiparous cows. There were positive correlations between colostral IgG and colostral vitamin A or colostral α-tocopherol in cows, and the higher adjusted R(2) was obtained in the prediction model of colostral IgG from age and colostral vitamin A. Colostral vitamin A was positively correlated with colostral ß-carotene or colostral α-tocopherol in cows, but there were no relationships between colostral IgA and colostral IgG or colostral fat-soluble vitamins. These results indicate that fat-soluble vitamin contents in colostrum of cows may change in similar patterns and high colostral vitamin A is related with high colostral IgG.
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Bovinos/metabolismo , Colostro/química , Imunoglobulina A/análise , Imunoglobulina G/análise , Vitamina A/análise , alfa-Tocoferol/análise , beta Caroteno/análise , Envelhecimento/metabolismo , Animais , Feminino , Japão , SolubilidadeRESUMO
Mortality and morbidity of neonates continue to be major problems in humans and animals, and immunoblogulin A (IgA) provides protection against microbial antigens at mucosal surfaces. The present study was conducted to clarify the effects of coumestrol administration to maternal mice during pregnancy and lactation on IgA antibody-secreting cells (ASC) in mammary glands in lactating mice. From 6.5 to 16.5 days post coitus and 1 to 13 days post partum (dpp), maternal mice were administered coumestrol at 200 µg/kg body weight/day. Coumestrol administration increased the number of IgA ASC and the messenger RNA expression of IgA C-region and vascular cell adhesion molecule-1 in mammary glands of maternal mice at 14 dpp, but coumestrol administration had no effect on the number of IgA ASC in the ileum. Coumestrol administration increased serum IgA concentration in maternal mice at 14 dpp, but IgA concentrations in serum, stomach contents, intestine and feces of neonatal mice were not affected by treatment. These results imply that coumestrol administration to maternal mice during pregnancy and lactation is effective in increasing the numbers of IgA ASC in mammary glands during lactation owing to the activated messenger RNA expressions of IgA C-region and vascular cell adhesion molecule-1 in mammary gland.
Assuntos
Células Produtoras de Anticorpos/efeitos dos fármacos , Cumestrol/farmacologia , Imunoglobulina A/fisiologia , Lactação , Glândulas Mamárias Animais/citologia , Camundongos/fisiologia , Fitoestrógenos/farmacologia , Prenhez/efeitos dos fármacos , Animais , Células Produtoras de Anticorpos/citologia , Cumestrol/administração & dosagem , Feminino , Íleo/citologia , Imunoensaio , Imunoglobulina A/sangue , Imuno-Histoquímica , Camundongos Endogâmicos ICR , Fitoestrógenos/administração & dosagem , Gravidez , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Study on antioxidants' radical scavenging processes and antioxidant capabilities is important for understanding the protective role of antioxidants against oxidative damages associated with some chronic diseases and food degradation. Traditional methods to monitor the radical scavenging by antioxidant require expensive instrument and sophisticated synthesis process. Herein, we report a novel, simple, colorimetric DNAzyme-based method to detect radical-scavenging capacity of antioxidant. In this new strategy, horseradish peroxidase (HRP) mimicking DNAzyme catalyzes the oxidation of ABTS2- (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) by H2O2 to generate blue/green ABTS.- radical, which can be scavenged by antioxidants resulting in color change. The typical kinetic curve of antioxidant-inhibited generation of ABTS.- shows distinct biphasic pattern, involving a lag phase (stage I) and a linear increase phase (stage II). kt value, the product of lag time (t) and the slope of the curve in stage II (k), was used as the parameter for antioxidant capacity determination. This DNAzyme-based antioxidant assay has been effectively used to quantitatively detect the concentrations of antioxidants and evaluate the antioxidant capabilities of a variety of antioxidants and some real samples. Compared with traditional antioxidant assays, this method is thermostable, pH stable, and time-saving, which presents a promising platform for antioxidant assay.