RESUMO
The surveillance and detection of zoonotic pathogens in animals is essential for predicting disease transmission pathways and the risks of spillover, but challenges include the costs, ethics and technical expertise required for vertebrate trapping, serum sampling and antibody or virus screening. Surveillance using haematophagous arthropods as a sampling tool offers a unique opportunity to obtain blood samples from a wide range of vertebrate species, allowing the study of host-mosquito associations, and host exposure to pathogens. We explored vertebrate diversity and potential Ross River virus (RRV) transmission pathways by analysing blood-fed mosquitoes collected in Brisbane, Australia. Host origins were identified using barcode sequencing, and host exposure to RRV was assessed using a modified plaque reduction neutralisation test. In total, 480 blood-fed mosquitoes were collected between February 2021 and May 2022. The host origins of 346 (72%) bloodmeals were identified, with humans (73%) and cattle (9%) comprising the dominant hosts. RRV seroprevalence was high in both vertebrate species with evidence of RRV exposure in 70% (21/30) of cattle and 52% (132/253) of humans. This is a novel, non-invasive method of estimating seroprevalence in vertebrate host populations. Our results highlight the potential of blood-fed mosquitoes to provide species-specific insights into pathogen transmission dynamics.
Assuntos
Culicidae , Ross River virus , Animais , Humanos , Culicidae/virologia , Bovinos , Ross River virus/patogenicidade , Especificidade de Hospedeiro , Estudos Soroepidemiológicos , Austrália/epidemiologia , Mosquitos Vetores/virologia , Vertebrados , Animais Selvagens/virologia , Infecções por Alphavirus/transmissão , Infecções por Alphavirus/virologia , Infecções por Alphavirus/sangue , Infecções por Alphavirus/epidemiologiaRESUMO
The very-low-density lipoprotein receptor (VLDLR) has been reported as an entry receptor for Semliki Forest (SFV) and Eastern equine encephalitis (EEEV) alphaviruses in cell cultures. However, the role of VLDLR in alphavirus pathogenesis and the extent to which other alphaviruses can engage VLDLR remains unclear. Here, using a surface protein-targeted CRISPR-Cas9 screen, we identify VLDLR as a receptor for Western equine encephalitis virus (WEEV) and demonstrate that it promotes the infection of multiple viruses in the WEE antigenic complex. In vivo studies show that the pathogenicity of WEEV, EEEV, and SFV, but not the distantly related Venezuelan equine encephalitis virus, is markedly diminished in VLDLR-deficient mice and that mice treated with a soluble VLDLR-Fc decoy molecule are protected against disease. Overall, these results expand our understanding of the role of VLDLR in alphavirus pathogenesis and provide a potential path for developing countermeasures against alphaviruses from different antigenic complexes.
Assuntos
Receptores de LDL , Animais , Receptores de LDL/metabolismo , Receptores de LDL/genética , Camundongos , Humanos , Camundongos Endogâmicos C57BL , Internalização do Vírus , Infecções por Alphavirus/virologia , Infecções por Alphavirus/patologia , Alphavirus/patogenicidade , Vírus da Encefalite Equina do Oeste/metabolismo , Vírus da Encefalite Equina do Oeste/patogenicidade , Camundongos Knockout , Células HEK293RESUMO
Frequent RNA virus mutations raise concerns about evolving virulent variants. The purpose of this study was to investigate genetic variation in salmonid alphavirus-3 (SAV3) over the course of an experimental infection in Atlantic salmon and brown trout. Atlantic salmon and brown trout parr were infected using a cohabitation challenge, and heart samples were collected for analysis of the SAV3 genome at 2-, 4- and 8-weeks post-challenge. PCR was used to amplify eight overlapping amplicons covering 98.8% of the SAV3 genome. The amplicons were subsequently sequenced using the Nanopore platform. Nanopore sequencing identified a multitude of single nucleotide variants (SNVs) and deletions. The variation was widespread across the SAV3 genome in samples from both species. Mostly, specific SNVs were observed in single fish at some sampling time points, but two relatively frequent (i.e., major) SNVs were observed in two out of four fish within the same experimental group. Two other, less frequent (i.e., minor) SNVs only showed an increase in frequency in brown trout. Nanopore reads were de novo clustered using a 99% sequence identity threshold. For each amplicon, a number of variant clusters were observed that were defined by relatively large deletions. Nonmetric multidimensional scaling analysis integrating the cluster data for eight amplicons indicated that late in infection, SAV3 genomes isolated from brown trout had greater variation than those from Atlantic salmon. The sequencing methods and bioinformatics pipeline presented in this study provide an approach to investigate the composition of genetic diversity during viral infections.
Assuntos
Infecções por Alphavirus , Alphavirus , Doenças dos Peixes , Variação Genética , Sequenciamento por Nanoporos , Salmo salar , Truta , Animais , Salmo salar/virologia , Doenças dos Peixes/virologia , Alphavirus/genética , Infecções por Alphavirus/veterinária , Infecções por Alphavirus/virologia , Sequenciamento por Nanoporos/veterinária , Sequenciamento por Nanoporos/métodos , Truta/virologiaRESUMO
Mayaro virus (MAYV) is the causative agent of Mayaro fever, which is characterized mainly by acute fever and long-term severe arthralgia, common manifestations of other arbovirus infections, making the correct diagnosis a challenge. Besides, MAYV infections have been reported in South America, especially in Brazil. However, the lack of vaccines or specific antiviral drugs to control these infections makes the search for new antivirals an urgent need. Herein, we evaluated the antiviral potential of synthetic ß-enaminoesters derivatives against MAYV replication and their pharmacokinetic and toxicological (ADMET) properties using in vitro and in silico strategies. For this purpose, Vero cells were infected with MAYV at an MOI of 0.1, treated with compounds (50 µM) for 24 h, and virus titers were quantified by plaque reduction assays. Compounds 2b (83.33%) and 2d (77.53%) exhibited the highest activity with inhibition rates of 83.33% and 77.53%, respectively. The most active compounds 2b (EC50 = 18.92 µM; SI > 52.85), and 2d (EC50 = 14.52 µM; SI > 68.87) exhibited higher potency and selectivity than the control drug suramin (EC50 = 38.97 µM; SI > 25.66). Then, we investigated the mechanism of action of the most active compounds. None of the compounds showed virucidal activity, neither inhibited virus adsorption, but compound 2b inhibited virus entry (62.64%). Also, compounds 2b and 2d inhibited some processes involved with the release of new virus particles. Finally, in silico results indicated good ADMET parameters of the most active compounds and reinforced their promising profile as drug candidates against MAYV.
Assuntos
Alphavirus , Antivirais , Ésteres , Replicação Viral , Antivirais/farmacologia , Antivirais/química , Chlorocebus aethiops , Animais , Células Vero , Ésteres/farmacologia , Ésteres/química , Alphavirus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Simulação por Computador , Brasil , Infecções por Alphavirus/tratamento farmacológico , Infecções por Alphavirus/virologiaRESUMO
Oral infection of mosquitoes by arboviruses often results in a large degree of variation in the amount of infectious virus between individual mosquitoes, even when the mosquitoes are from inbred laboratory strains. This variability in arbovirus load has been shown to affect virus transmissibility. Previously, our group described population genetic and specific infectivity differences between the virus populations found in high and low titer Aedes aegypti mosquitoes that had been orally infected with Sindbis virus (SINV). In this study, we sought to investigate whether there were also differences in transcriptomic response between these high and low titer mosquitoes. Results from the transcriptomic data analysis showed that more genes involved in antiviral activity, endopeptidase activity, and methyltransferase activity were upregulated in low titer mosquitoes than in high titer mosquitoes, relative to blood-fed controls. Meanwhile, genes involved in ion transport, energy metabolism, acetylation, glycosylation, lipid metabolism, and transport tended to be upregulated in high titer mosquitoes more than in low titer mosquitoes, relative to blood-fed mosquitoes. Overall, genes involved in antiviral activities tended to be upregulated in low titer mosquitoes while genes involved in proviral activities were mostly upregulated in high titer mosquitoes. This study has identified a number of candidate mosquito genes that are putatively associated with SINV titer variability after oral infection of Ae. aegypti, and these can now be investigated in order to ascertain their roles in virus replication and their contributions to determining vector competence.
Assuntos
Aedes , Mosquitos Vetores , Sindbis virus , Transcriptoma , Carga Viral , Animais , Aedes/virologia , Aedes/genética , Sindbis virus/fisiologia , Sindbis virus/genética , Mosquitos Vetores/virologia , Mosquitos Vetores/genética , Perfilação da Expressão Gênica , Infecções por Alphavirus/virologia , Infecções por Alphavirus/transmissão , Feminino , Replicação ViralRESUMO
Mayaro virus (MAYV) is an arbovirus first isolated in Trinidad and Tobago in 1954. MAYV is the causative agent of Mayaro fever, which is characterised by high fever, maculopapular rash, myalgia and arthralgia. The potential for chronic arthralgia is of particular clinical concern. Currently, MAYV outbreaks are restricted to South and Central America, with some cases reported in Africa as well as several imported cases in Europe. However, in recent years, MAYV has become a growing global concern due to its potential to emerge into urban transmission cycles. Challenges faced with diagnostics, as well as a lack of specific antivirals or licensed vaccines further exacerbate the potential global health threat posed by MAYV. In this review, we discuss this emerging arboviral threat with a particular focus on the current treatment and vaccine development efforts. Overall, MAYV remains a neglected arbovirus due to its limited area of transmission. However, with the potential of its urbanisation and expanding circulation, the threat MAYV poses to global health cannot be overlooked. Further research into the improvement of current diagnostics, as well as the development of efficacious antivirals and vaccines will be crucial to help prevent and manage potential MAYV outbreaks.
Assuntos
Infecções por Alphavirus , Alphavirus , Humanos , Alphavirus/isolamento & purificação , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/virologia , Infecções por Alphavirus/transmissão , Animais , América/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Surtos de Doenças , Vacinas Virais/imunologia , Antivirais/uso terapêutico , Saúde GlobalRESUMO
The host interferon pathway upregulates intrinsic restriction factors in response to viral infection. Many of them block a diverse range of viruses, suggesting that their antiviral functions might have been shaped by multiple viral families during evolution. Host-virus conflicts have led to the rapid adaptation of host and viral proteins at their interaction hotspots. Hence, we can use evolutionary genetic analyses to elucidate antiviral mechanisms and domain functions of restriction factors. Zinc finger antiviral protein (ZAP) is a restriction factor against RNA viruses such as alphaviruses, in addition to other RNA, retro-, and DNA viruses, yet its precise antiviral mechanism is not fully characterized. Previously, an analysis of 13 primate ZAP orthologs identified three positively selected residues in the poly(ADP-ribose) polymerase-like domain. However, selective pressure from ancient alphaviruses and others likely drove ZAP adaptation in a wider representation of mammals. We performed positive selection analyses in 261 mammalian ZAP using more robust methods with complementary strengths and identified seven positively selected sites in all domains of the protein. We generated ZAP inducible cell lines in which the positively selected residues of ZAP are mutated and tested their effects on alphavirus replication and known ZAP activities. Interestingly, the mutant in the second WWE domain of ZAP (N658A) is dramatically better than wild-type ZAP at blocking replication of Sindbis virus and other ZAP-sensitive alphaviruses due to enhanced viral translation inhibition. The N658A mutant is adjacent to the previously reported poly(ADP-ribose) (PAR) binding pocket, but surprisingly has reduced binding to PAR. In summary, the second WWE domain is critical for engineering a more potent ZAP and fluctuations in PAR binding modulate ZAP antiviral activity. Our study has the potential to unravel the role of ADP-ribosylation in the host innate immune defense and viral evolutionary strategies that antagonize this post-translational modification.
Assuntos
Infecções por Alphavirus , Alphavirus , Humanos , Animais , Alphavirus/genética , Infecções por Alphavirus/virologia , Infecções por Alphavirus/genética , Domínios Proteicos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Seleção Genética , Evolução Molecular , Proteínas RepressorasRESUMO
Chikungunya (CHIKV) and Mayaro (MAYV) viruses are arthritogenic alphaviruses that promote an incapacitating and long-lasting inflammatory muscle-articular disease. Despite studies pointing out the importance of skeletal muscle (SkM) in viral pathogenesis, the long-term consequences on its physiology and the mechanism of persistence of symptoms are still poorly understood. Combining molecular, morphological, nuclear magnetic resonance imaging, and histological analysis, we conduct a temporal investigation of CHIKV and MAYV replication in a wild-type mice model, focusing on the impact on SkM composition, structure, and repair in the acute and late phases of infection. We found that viral replication and induced inflammation promote a rapid loss of muscle mass and reduction in fiber cross-sectional area by upregulation of muscle-specific E3 ubiquitin ligases MuRF1 and Atrogin-1 expression, both key regulators of SkM fibers atrophy. Despite a reduction in inflammation and clearance of infectious viral particles, SkM atrophy persists until 30 days post-infection. The genomic CHIKV and MAYV RNAs were still detected in SkM in the late phase, along with the upregulation of chemokines and anti-inflammatory cytokine expression. In agreement with the involvement of inflammatory mediators on induced atrophy, the neutralization of TNF and a reduction in oxidative stress using monomethyl fumarate, an agonist of Nrf2, decreases atrogen expression and atrophic fibers while increasing weight gain in treated mice. These data indicate that arthritogenic alphavirus infection could chronically impact body SkM composition and also harm repair machinery, contributing to a better understanding of mechanisms of arthritogenic alphavirus pathogenesis and with a description of potentially new targets of therapeutic intervention.
Assuntos
Vírus Chikungunya , Músculo Esquelético , Atrofia Muscular , Estresse Oxidativo , Animais , Atrofia Muscular/virologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Camundongos , Músculo Esquelético/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/virologia , Febre de Chikungunya/patologia , Febre de Chikungunya/virologia , Febre de Chikungunya/metabolismo , Inflamação/patologia , Inflamação/metabolismo , Inflamação/virologia , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Replicação Viral , Camundongos Endogâmicos C57BL , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Infecções por Alphavirus/virologia , Infecções por Alphavirus/patologia , Infecções por Alphavirus/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/genética , Modelos Animais de Doenças , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
Arthritogenic alphaviruses pose a significant public health concern due to their ability to cause joint inflammation, with emerging evidence of potential neurological consequences. In this review, we examine the immunopathology and immune evasion strategies employed by these viruses, highlighting their complex mechanisms of pathogenesis and neurological implications. We delve into how these viruses manipulate host immune responses, modulate inflammatory pathways, and potentially establish persistent infections. Further, we explore their ability to breach the blood-brain barrier, triggering neurological complications, and how co-infections exacerbate neurological outcomes. This review synthesizes current research to provide a comprehensive overview of the immunopathological mechanisms driving arthritogenic alphavirus infections and their impact on neurological health. By highlighting knowledge gaps, it underscores the need for research to unravel the complexities of virus-host interactions. This deeper understanding is crucial for developing targeted therapies to address both joint and neurological manifestations of these infections.
Assuntos
Infecções por Alphavirus , Alphavirus , Barreira Hematoencefálica , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Humanos , Alphavirus/patogenicidade , Alphavirus/imunologia , Animais , Infecções por Alphavirus/imunologia , Infecções por Alphavirus/virologia , Interações Hospedeiro-Patógeno/imunologia , Barreira Hematoencefálica/imunologia , Doenças do Sistema Nervoso/imunologia , Doenças do Sistema Nervoso/virologiaRESUMO
Molecular surveillance is vital for monitoring arboviruses, often employing genus-specific quantitative reverse-transcription polymerase chain reaction (RT-qPCR). Despite this, an overlooked chikungunya fever outbreak occurred in Yunnan province, China, in 2019 and false negatives are commonly encountered during alphaviruses screening practice, highlighting the need for improved detection methods. In this study, we developed an improved alphaviruses-specific RT-qPCR capable of detecting chikungunya virus, eastern equine encephalitis virus, western equine encephalitis virus, Venezuelan equine encephalitis virus, Sindbis virus, Mayaro virus, and Ross River virus with high sensitivity and specificity. The assay identified three chikungunya virus-positive cases out of 188 sera retrospectively. Later genetic characterization suggested that imported cases from neighboring countries may be responsible for the neglected chikungunya fever outbreak of 2019 in Yunnan. Our findings underscore the value of improved alphaviruses-specific RT-qPCR in bolstering alphaviruses surveillance and informing preventive strategies.
Assuntos
Infecções por Alphavirus , Alphavirus , Vírus Chikungunya , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Humanos , Alphavirus/genética , Alphavirus/isolamento & purificação , Infecções por Alphavirus/diagnóstico , Infecções por Alphavirus/virologia , Infecções por Alphavirus/prevenção & controle , Infecções por Alphavirus/epidemiologia , China/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Estudos Retrospectivos , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/virologia , Febre de Chikungunya/epidemiologia , Vírus da Encefalite Equina do Leste/genética , Surtos de Doenças/prevenção & controle , Sindbis virus/genética , Vírus da Encefalite Equina do Oeste/genética , Ross River virus/genética , Ross River virus/isolamento & purificação , Vírus da Encefalite Equina Venezuelana/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , RNA Viral/genéticaRESUMO
Mayaro virus (MAYV), a mosquito-borne alphavirus, is considered an emerging threat to public health with epidemic potential. Phylogenetic studies show the existence of three MAYV genotypes. In this study, we provide a preliminary analysis of the pathogenesis of all three MAYV genotypes in cynomolgus macaques (Macaca facicularis, Mauritian origin). Significant MAYV-specific RNAemia and viremia were detected during acute infection in animals challenged intravenously with the three MAYV genotypes, and strong neutralizing antibody responses were observed. MAYV RNA was detected at high levels in lymphoid tissues, joint muscle and synovia over 1 month after infection, suggesting that this model could serve as a promising tool in studying MAYV-induced chronic arthralgia, which can persist for years. Significant leucopenia was observed across all MAYV genotypes, peaking with RNAemia. Notable differences in the severity of acute RNAemia and composition of cytokine responses were observed among the three MAYV genotypes. Our model showed no outward signs of clinical disease, but several major endpoints for future MAYV pathology and intervention studies are described. Disruptions to normal blood cell counts and cytokine responses were markedly distinct from those observed in macaque models of CHIKV infection, underlining the importance of developing non-human primate models specific to MAYV infection.
Assuntos
Infecções por Alphavirus , Alphavirus , Genótipo , Macaca fascicularis , RNA Viral , Viremia , Animais , Macaca fascicularis/virologia , Alphavirus/genética , Alphavirus/patogenicidade , Alphavirus/classificação , Alphavirus/isolamento & purificação , Infecções por Alphavirus/virologia , Infecções por Alphavirus/veterinária , Viremia/virologia , RNA Viral/genética , Anticorpos Antivirais/sangue , Anticorpos Neutralizantes/sangue , Modelos Animais de Doenças , Filogenia , Citocinas/genética , Citocinas/sangueRESUMO
Barmah Forest virus (BFV) is a mosquito-borne virus that causes arthralgia with accompanying rash, fever, and myalgia in humans. The virus is mainly found in Australia and has caused outbreaks associated with significant health concerns. As the sole representative of the Barmah Forest complex within the genus Alphavirus, BFV is not closely related genetically to other alphaviruses. Notably, basic knowledge of BFV molecular virology has not been well studied due to a lack of critical investigative tools such as an infectious clone. Here we describe the construction of an infectious BFV cDNA clone based on Genbank sequence and demonstrate that the clone-derived virus has in vitro and in vivo properties similar to naturally occurring virus, BFV field isolate 2193 (BFV2193-FI). A substitution in nsP4, V1911D, which was identified in the Genbank reference sequence, was found to inhibit virus rescue and replication. T1325P substitution in nsP2 selected during virus passaging was shown to be an adaptive mutation, compensating for the inhibitory effect of nsP4-V1911D. The two mutations were associated with changes in viral non-structural polyprotein processing and type I interferon (IFN) induction. Interestingly, a nuclear localization signal, active in mammalian but not mosquito cells, was identified in nsP3. A point mutation abolishing nsP3 nuclear localization attenuated BFV replication. This effect was more prominent in the presence of type I interferon signaling, suggesting nsP3 nuclear localization might be associated with IFN antagonism. Furthermore, abolishing nsP3 nuclear localization reduced virus replication in mice but did not significantly affect disease.IMPORTANCEBarmah Forest virus (BFV) is Australia's second most prevalent arbovirus, with approximately 1,000 cases reported annually. The clinical symptoms of BFV infection include rash, polyarthritis, arthralgia, and myalgia. As BFV is not closely related to other pathogenic alphaviruses or well-studied model viruses, our understanding of its molecular virology and mechanisms of pathogenesis is limited. There is also a lack of molecular tools essential for corresponding studies. Here we describe the construction of an infectious clone of BFV, variants harboring point mutations, and sequences encoding marker protein. In infected mammalian cells, nsP3 of BFV was located in the nuclei. This finding extends our understanding of the diverse mechanisms used by alphavirus replicase proteins to interact with host cells. Our novel observations highlight the complex synergy through which the viral replication machinery evolves to correct mutation errors within the viral genome.
Assuntos
Infecções por Alphavirus , Alphavirus , Genoma Viral , Proteínas não Estruturais Virais , Replicação Viral , Replicação Viral/genética , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Animais , Alphavirus/genética , Alphavirus/patogenicidade , Camundongos , Infecções por Alphavirus/virologia , Genoma Viral/genética , Linhagem Celular , Humanos , AustráliaRESUMO
The Alphavirus genus includes viruses that cause encephalitis due to neuroinvasion and viruses that cause arthritis due to acute and chronic inflammation. There is no approved therapeutic for alphavirus infections, but significant efforts are ongoing, more so in recent years, to develop vaccines and therapeutics for alphavirus infections. This review article highlights some of the major advances made so far to identify small molecules that can selectively target the structural and the nonstructural proteins in alphaviruses with the expectation that persistent investigation of an increasingly expanding chemical space through a variety of structure-based design and high-throughput screening strategies will yield candidate drugs for clinical studies. While most of the works discussed are still in the early discovery to lead optimization stages, promising avenues remain for drug development against this family of viruses.
Assuntos
Alphavirus , Antivirais , Proteínas não Estruturais Virais , Alphavirus/efeitos dos fármacos , Alphavirus/química , Antivirais/farmacologia , Antivirais/química , Humanos , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Infecções por Alphavirus/tratamento farmacológico , Infecções por Alphavirus/virologia , Animais , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/antagonistas & inibidoresRESUMO
A recombinant Ross River virus (RRV) that contains the fluorescent protein mCherry fused to the non-structural protein 3 (nsP3) was constructed, which allowed real-time imaging of viral replication. RRV-mCherry contained either the natural opal stop codon after the nsP3 gene or was constructed without a stop codon. The mCherry fusion protein did not interfere with the viral life cycle and deletion of the stop codon did not change the replication capacity of RRV-mCherry. Comparison of RRV-mCherry and chikungunya virus-mCherry infections, however, showed a cell type-dependent delay in RRV-mCherry replication in HEK 293T cells. This delay was not caused by differences in cell entry, but rather by an impeded nsP expression caused by the RRV inhibitor ZAP (zinc finger CCCH-Type, antiviral 1). The data indicate that viral replication of alphaviruses is cell-type dependent, and might be unique for each alphavirus.
Assuntos
Códon de Terminação , Ross River virus , Proteínas não Estruturais Virais , Replicação Viral , Replicação Viral/genética , Humanos , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Ross River virus/genética , Ross River virus/fisiologia , Células HEK293 , Animais , Códon de Terminação/genética , Linhagem Celular , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Infecções por Alphavirus/virologia , Células Vero , Chlorocebus aethiops , Proteína Vermelha FluorescenteRESUMO
The mitochondrial anti-viral signaling (MAVS) protein is an intermediary adaptor protein of retinoic acid-inducible gene-1 (RIG-I) like receptor (RLR) signaling, which activates the transcription factor interferon (IFN) regulatory factor 3 (IRF3) and NF-kB to produce type I IFNs. MAVS expression has been reported in different fish species, but few studies have shown its functional role in anti-viral responses to fish viruses. In this study, we used the transcription activator-like effector nuclease (TALEN) as a gene editing tool to disrupt the function of MAVS in Chinook salmon (Oncorhynchus tshawytscha) embryonic cells (CHSE) to understand its role in induction of interferon I responses to infections with the (+) RNA virus salmonid alphavirus subtype 3 (SAV-3), and the dsRNA virus infectious pancreatic necrosis virus (IPNV) infection. A MAVS-disrupted CHSE clone with a 7-aa polypeptide (GVFVSRV) deletion mutation at the N-terminal of the CARD domain infected with SAV-3 resulted in significantly lower expression of IRF3, IFNa, and ISGs and increased viral titer (1.5 log10) compared to wild-type. In contrast, the IPNV titer in MAVS-disrupted cells was not different from the wild-type. Furthermore, overexpression of salmon MAVS in MAVS-disrupted CHSE cells rescued the impaired type I IFN-mediated anti-viral effect against SAV-3.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Alphavirus , Doenças dos Peixes , Vírus da Necrose Pancreática Infecciosa , Transdução de Sinais , Replicação Viral , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Alphavirus/imunologia , Alphavirus/fisiologia , Infecções por Alphavirus/imunologia , Infecções por Alphavirus/virologia , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/veterinária , Infecções por Birnaviridae/virologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/metabolismo , Vírus da Necrose Pancreática Infecciosa/fisiologia , Vírus da Necrose Pancreática Infecciosa/imunologia , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , Salmão/virologia , Salmão/imunologiaRESUMO
Background: Alphaviruses are a diverse group of pathogens that have garnered considerable attention due to their impact on human health. By investigating alphavirus receptors, researchers can elucidate viral entry mechanisms and gain important clues for the prevention and treatment of viral diseases. This study presents an in-depth analysis of the research progress made in the field of alphavirus receptors through bibliometric analysis. Methods: This study encompasses various aspects, including historical development, annual publication trends, author and cited-author analysis, institutional affiliations, global distribution of research contributions, reference analysis with strongest citation bursts, keyword analysis, and a detailed exploration of recent discoveries in alphavirus receptor research. Results: The results of this bibliometric analysis highlight key milestones in alphavirus receptor research, demonstrating the progression of knowledge in this field over time. Additionally, the analysis reveals current research hotspots and identifies emerging frontiers, which can guide future investigations and inspire novel therapeutic strategies. Conclusion: This study provides an overview of the state of the art in alphavirus receptor research, consolidating the existing knowledge and paving the way for further advancements. By shedding light on the significant developments and emerging areas of interest, this study serves as a valuable resource for researchers, clinicians, and policymakers engaged in combating alphavirus infections and improving public health.
Assuntos
Alphavirus , Bibliometria , Humanos , Receptores Virais/metabolismo , Animais , Internalização do Vírus , Infecções por Alphavirus/virologia , Pesquisa Biomédica/tendênciasRESUMO
Taï Forest virus (TAFV) is a negative-sense RNA virus in the Filoviridae family. TAFV has caused only a single human infection, but several disease outbreaks in chimpanzees have been linked to this virus. Limited research has been done on this human-pathogenic virus. We sought to establish an animal model to assess TAFV disease progression and pathogenicity at our facility. We had access to two different viral stock preparations from different institutions, both originating from the single human case. Type I interferon receptor knockout mice were inoculated with TAFV stock 1 or stock 2 by the intraperitoneal route. Inoculation resulted in 100% survival with no disease regardless of viral stock preparation or infectious dose. Next, cynomolgus macaques were inoculated with TAFV stock 1 or stock 2. Inoculation with TAFV stock 1 resulted in 100% survival and robust TAFV glycoprotein-specific IgG responses including neutralizing antibodies. In contrast, macaques infected with TAFV stock 2 developed disease and were euthanized 8-11 days after infection exhibiting viremia, thrombocytopenia, and increased inflammatory mediators identified by transcriptional analysis. Histopathologic analysis of tissue samples collected at necropsy confirmed classic filovirus disease in numerous organs. Genomic differences in both stock preparations were mapped to several viral genes which may have contributed to disease severity. Taken together, we demonstrate that infection with the two TAFV stocks resulted in no disease in mice and opposing disease phenotypes in cynomolgus macaques, highlighting the impact of viral stock propagation on pathogenicity in animal models.
Assuntos
Modelos Animais de Doenças , Macaca fascicularis , Camundongos Knockout , Animais , Camundongos , Humanos , Replicação Viral , Infecções por Alphavirus/virologia , Infecções por Alphavirus/patologia , Receptor de Interferon alfa e beta/genéticaRESUMO
Various low-density lipoprotein receptors (LPRs) have been identified as entry factors for alphaviruses, and structures of the corresponding virion-receptor complexes have been determined. Here, we analyze the similarities and differences in the receptor binding modes of multiple alphaviruses to understand their ability to infect a wide range of hosts. We further discuss the challenges associated with the development of broad-spectrum treatment strategies against a diverse range of alphaviruses.
Assuntos
Alphavirus , Antivirais , Receptores de LDL , Internalização do Vírus , Animais , Humanos , Alphavirus/efeitos dos fármacos , Alphavirus/fisiologia , Alphavirus/genética , Infecções por Alphavirus/tratamento farmacológico , Infecções por Alphavirus/virologia , Antivirais/uso terapêutico , Antivirais/farmacologia , Ligação Proteica , Receptores de LDL/metabolismo , Receptores de LDL/genética , Receptores Virais/metabolismo , Receptores Virais/química , Vírion/metabolismo , Internalização do Vírus/efeitos dos fármacosRESUMO
BACKGROUND: Chikungunya virus (CHIKV) and O'nyong nyong virus (ONNV) are phylogenetically related alphaviruses in the Semliki Forest Virus (SFV) antigenic complex of the Togaviridae family. There are limited data on the circulation of these two viruses in Burkina Faso. The aim of our study was to assess their circulation in the country by determining seroprevalence to each of the viruses in blood donor samples and by retrospective molecular and serological testing of samples collected as part of national measles and rubella surveillance. METHODOLOGY/PRINCIPAL FINDINGS: All blood donor samples were analyzed on the Luminex platform using CHIKV and ONNV E2 antigens. Patient samples collected during national measles-rubella surveillance were screened by an initial ELISA for CHIKV IgM (CHIKjj Detect IgM ELISA) at the national laboratory. The positive samples were then analyzed by a second ELISA test for CHIKV IgM (CDC MAC-ELISA) at the reference laboratory. Finally, samples that had IgM positive results for both ELISA tests and had sufficient residual volume were tested by plaque reduction neutralization testing (PRNT) for CHIKV and ONNV. These same patient samples were also analyzed by rRT-PCR for CHIKV. Among the blood donor specimens, 55.49% of the samples were positive for alphaviruses including both CHIKV and ONNV positive samples. Among patient samples collected as part of national measles and rubella surveillance, 3.09% were IgM positive for CHIKV, including 2.5% confirmed by PRNT. PRNT failed to demonstrate any ONNV infections in these samples. No samples tested by RT-qPCR. had detectable CHIKV RNA. CONCLUSIONS/SIGNIFICANCE: Our results suggest that CHIKV and ONNV have been circulating in the population of Burkina Faso and may have been confused with malaria, dengue fever or other febrile diseases such as measles or rubella. Our study underscores the necessity to enhance arbovirus surveillance systems in Burkina Faso.
Assuntos
Infecções por Alphavirus , Anticorpos Antivirais , Vírus Chikungunya , Ensaio de Imunoadsorção Enzimática , Imunoglobulina M , Vírus O'nyong-nyong , Humanos , Burkina Faso/epidemiologia , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus Chikungunya/isolamento & purificação , Anticorpos Antivirais/sangue , Estudos Soroepidemiológicos , Imunoglobulina M/sangue , Masculino , Feminino , Adulto , Vírus O'nyong-nyong/genética , Vírus O'nyong-nyong/isolamento & purificação , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/virologia , Infecções por Alphavirus/diagnóstico , Infecções por Alphavirus/sangue , Adulto Jovem , Adolescente , Estudos Retrospectivos , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Febre de Chikungunya/sangue , Febre de Chikungunya/diagnóstico , Pessoa de Meia-Idade , Doadores de Sangue , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologiaRESUMO
Newly emerging viruses, primarily zoonotic or vector-borne, pose a persistent threat to public health and have led to outbreaks of global concern [...].