Recombinant Viruses from the Picornaviridae Family Occurring in Racing Pigeons.

Viruses from Picornaviridae family are known pathogens of poultry, although the information on their occurrence and pathogenicity in pigeons is scarce. In this research, efforts are made to broaden the knowledge on Megrivirus B and Pigeon picornavirus B prevalence, phylogenetic relationship with other avian picornaviruses and their possible connection with enteric disease in racing pigeons. As a result of Oxford Nanopore Sequencing, five Megrivirus and two pigeon picornavirus B-like genome sequences were recovered, among which three recombinant strains were detected. The recombinant fragments represented an average of 10.9% and 25.5% of the genome length of the Pigeon picornavirus B and Megrivirus B reference strains, respectively. The phylogenetic analysis revealed that pigeons are carriers of species-specific picornaviruses. TaqMan qPCR assays revealed 7.8% and 19.0% prevalence of Megrivirus B and 32.2% and 39.7% prevalence of Pigeon picornavirus B in the group of pigeons exhibiting signs of enteropathy and in the group of asymptomatic pigeons, respectively. In turn, digital droplet PCR showed a considerably higher number of genome copies of both viruses in sick than in asymptomatic pigeons. The results of quantitative analysis leave the role of picornaviruses in enteropathies of pigeons unclear.

Development of a CRISPR/Cas12a-based fluorescent detection method of Senecavirus A.

BACKGROUND: Senecavirus A (SVA), identified in 2002, is known to cause porcine idiopathic vesicular disease (PIVD), which presents with symptoms resembling other vesicular diseases. This similarity complicates field diagnosis. Conventional molecular diagnostic techniques are limited by their cost, sensitivity, and requirement for complicated instrumentation. Therefore, developing an effective and accurate diagnostic method is crucial for timely identification and isolation of affected pigs, thereby preventing further disease spread. METHODS: In this study, we developed a highly-specific and ultra-sensitive SVA detection method powered by CRISPR/Cas12a. To enhance the availability in laboratories with varied equipment conditions, microplate reader and ultraviolet light transilluminator were introduced. Moreover, PCR amplification has also been incorporated into this method to improve sensitivity. The specificity and sensitivity of this method were determined following the preparation of the recombinant Cas12a protein and optimization of the CRISPR/Cas12a-based trans-cleavage system. RESULTS: The method demonstrated no cross-reactivity with ten kinds of viruses of swine. The minimum template concentration required to activate substantial trans-cleavage activity was determined to be 106 copies/µL of SVA templates. However, when PCR amplification was incorporated, the method achieved a detection limit of one copy of SVA templates per reaction. It also exhibited 100% accuracy in simulated sample testing. The complete testing process does not exceed three hours. CONCLUSIONS: Importantly, this method utilizes standard laboratory equipment, making it accessible for use in resource-limited settings and facilitating widespread and ultra-sensitive screening during epidemics. Overall, the development of this method not only broadens the array of tools available for detecting SVA but also holds significant promise for controlling the spread of PIVD.

Interfering factors in the diagnosis of Senecavirus A.

BACKGROUND: Senecavirus A (SV-A) is an RNA virus that belongs to the genus Senecavirus within the family Picornaviridae. This study aimed to analyze factors that can influence the molecular diagnosis of Senecavirus A, such as oligonucleotides, RNA extraction methods, and RT-qPCR kits. METHODS: Samples from suspected cases of vesicular disease in Brazilian pigs were analyzed for foot-and-mouth disease, swine vesicular disease, and vesicular stomatitis. All tested negative for these diseases but positive for SV-A. RT-qPCR tests were used, comparing different reagent kits and RNA extraction methods. Sensitivity and repeatability were evaluated, demonstrating efficacy in detecting SV-A in clinical samples. RESULTS: In RNA extraction, significant reduction in Cq values was observed with initial dilutions, particularly with larger supernatant volumes. Trizol and Maxwell showed greater sensitivity in automated equipment protocols, though results varied in tissue tests. RT-qPCR kit comparison revealed differences in amplification using viral RNA but minimal differences with plasmid DNA. Sensitivity among methods was comparable, with slight variations in non-amplified samples. Repeatability tests showed consistent results among RT-qPCRs, demonstrating similarity between methods despite minor discrepancies in Cq values. CONCLUSIONS: Trizol, silica columns, and semi-automated extraction were compared, as well as different RT-qPCR kits. The study found significant variations that could impact the final diagnosis.

Longitudinal analysis of the enteric virome in paediatric subjects from the Free State Province, South Africa, reveals early gut colonisation and temporal dynamics.

The gut of healthy neonates is devoid of viruses at birth, but rapidly becomes colonised by normal viral commensals that aid in important physiological functions like metabolism but can, in some instances, result in gastrointestinal illnesses. However, little is known about how this colonisation begins, its variability and factors shaping the gut virome composition. Thus, understanding the development, assembly, and progression of enteric viral communities over time is key. To explore early-life virome development, metagenomic sequencing was employed in faecal samples collected longitudinally from a cohort of 17 infants during their first six months of life. The gut virome analysis revealed a diverse and dynamic viral community, formed by a richness of different viruses infecting humans, non-human mammals, bacteria, and plants. Eukaryotic viruses were detected as early as one week of life, increasing in abundance and diversity over time. Most of the viruses detected are commonly associated with gastroenteritis and include members of the Caliciviridae, Picornaviridae, Astroviridae, Adenoviridae, and Sedoreoviridae families. The most common co-occurrences involved asymptomatic norovirus-parechovirus, norovirus-sapovirus, sapovirus-parechovirus, observed in at least 40 % of the samples. Majority of the plant-derived viruses detected in the infants' gut were from the Virgaviridae family. This study demonstrates the first longitudinal characterisation of the gastrointestinal virome in infants, from birth up to 6 months of age, in sub-Saharan Africa. Overall, the findings from this study delineate the composition and variability of the healthy infants' gut virome over time, which is a significant step towards understanding the dynamics and biogeography of viral communities in the infant gut.

ZBP1 inhibits the replication of Senecavirus A by enhancing NF-κB signaling pathway mediated antiviral response in porcine alveolar macrophage 3D4/21 cells.

BACKGROUND: Senecavirus A (SVA) caused porcine idiopathic vesicular disease (PIVD) showing worldwide spread with economic losses in swine industry. Although some progress has been made on host factors regulating the replication of SVA, the role of Z-DNA binding protein 1 (ZBP1) remains unclear. METHODS: The expression of ZBP1 in SVA-infected 3D/421 cells was analyzed by quantitative real-time PCR (qRT-PCR) and western blot. Western blot and qRT-PCR were used to detect the effects of over and interference expression of ZBP1 on SVA VP2 gene and protein. Viral growth curves were prepared to measure the viral proliferation. The effect on type I interferons (IFNs), interferon-stimulated genes (ISGs), and pro-inflammatory cytokines in SVA infection was analyzed by qRT-PCR. Western blot was used to analysis the effect of ZBP1 on NF-κB signaling pathway and inhibitor are used to confirm. RESULTS: ZBP1 is shown to inhibit the replication of SVA by enhancing NF-κB signaling pathway mediated antiviral response. SVA infection significantly up-regulated the expression of ZBP1 in 3D4/21 cells. Infection of cells with overexpression of ZBP1 showed that the replication of SVA was inhibited with the enhanced expression of IFNs (IFN-α, IFN-ß), ISGs (ISG15, PKR, and IFIT1) and pro-inflammatory cytokines (IL-6, IL-8, and TNF-α), while, infected-cells with interference expression of ZBP1 showed opposite effects. Further results showed that antiviral effect of ZBP1 is achieved by activation the NF-κB signaling pathway and specific inhibitor of NF-κB also confirmed this. CONCLUSIONS: ZBP1 is an important host antiviral factor in SVA infection and indicates that ZBP1 may be a novel target against SVA.

Virus-like particle-based multipathogen vaccine of FMD and SVA elicits balanced and broad protective efficacy in mice and pigs.

Inactivated vaccines lack the capability to serologically differentiate between infected and vaccinated animals, thereby impeding the effective eradication of pathogen. Conversely, vaccines based on virus-like particles (VLPs) emulate natural viruses in both size and antigenic structure, presenting a promising alternative to overcome these limitations. As the complexity of swine infectious diseases increases, the increase of vaccine types and doses may intensify the stress response. This exacerbation can lead to diminished productivity, failure of immunization, and elevated costs. Given the critical dynamics of co-infection and the clinically indistinguishable symptoms associated with foot-and-mouth disease virus (FMDV) and senecavirus A (SVA), there is a dire need for an efficacious intervention. To address these challenges, we developed a combined vaccine composed of three distinct VLPs, specifically designed to target SVA and FMDV serotypes O and A. Our research demonstrates that this trivalent VLP vaccine induces antigen-specific and robust serum antibody responses, comparable to those produced by the respective monovalent vaccines. Moreover, the immune sera from the combined VLP vaccine strongly neutralized FMDV type A and O, and SVA, with neutralization titers comparable to those of the individual vaccines, indicating a high level of immunogenic compatibility among the three VLP components. Importantly, the combined VLPs vaccines-immunized sera conferred efficient protection against single or mixed infections with FMDV type A and O, and SVA viruses in pigs. In contrast, individual vaccines could only protect pigs against homologous virus infections and not against heterologous challenges. This study presents a novel combined vaccines candidate against FMD and SVA, and provides new insights for the development of combination vaccines for other viral swine diseases.

Seneca valley virus 3C protease blocks EphA2-Mediated mTOR activation to facilitate viral replication.

The Seneca Valley virus (SVV) is a recently discovered porcine pathogen that causes vesicular diseases and poses a significant threat to the pig industry worldwide. Erythropoietin-producing hepatoma receptor A2 (EphA2) is involved in the activation of the AKT/mTOR signaling pathway, which is involved in autophagy. However, the regulatory relationship between SVV and EphA2 remains unclear. In this study, we demonstrated that EphA2 is proteolysed in SVV-infected BHK-21 and PK-15 cells. Overexpression of EphA2 significantly inhibited SVV replication, as evidenced by decreased viral protein expression, viral titers, and viral load, suggesting an antiviral function of EphA2. Subsequently, viral proteins involved in the proteolysis of EphA2 were screened, and the SVV 3C protease (3Cpro) was found to be responsible for this cleavage, depending on its protease activity. However, the protease activity sites of 3Cpro did not affect the interactions between 3Cpro and EphA2. We further determined that EphA2 overexpression inhibited autophagy by activating the mTOR pathway and suppressing SVV replication. Taken together, these results indicate that SVV 3Cpro targets EphA2 for cleavage to impair its EphA2-mediated antiviral activity and emphasize the potential of the molecular interactions involved in developing antiviral strategies against SVV infection.

Phylodynamic analysis of foot-and-mouth disease virus evolution in Mar Chiquita, Argentina.

Foot-and-mouth disease is a highly contagious disease affecting cloven-hoofed animals, resulting in considerable economic losses. Its causal agent is foot-and-mouth disease virus (FMDV), a picornavirus. Due to its error-prone replication and rapid evolution, the transmission and evolutionary dynamics of FMDV can be studied using genomic epidemiological approaches. To analyze FMDV evolution and identify possible transmission routes in an Argentinean region, field samples that tested positive for FMDV by PCR were obtained from 21 farms located in the Mar Chiquita district. Whole FMDV genome sequences were obtained by PCR amplification in seven fragments and sequencing using the Sanger technique. The genome sequences obtained from these samples were then analyzed using phylogenetic, phylogeographic, and evolutionary approaches. Three local transmission clusters were detected among the sampled viruses. The dataset was analyzed using Bayesian phylodynamic methods with appropriate coalescent and relaxed molecular clock models. The estimated mean viral evolutionary rate was 1.17 × 10- 2 substitutions/site/year. No significant differences in the rate of viral evolution were observed between farms with vaccinated animals and those with unvaccinated animals. The most recent common ancestor of the sampled sequences was dated to approximately one month before the first reported case in the outbreak. Virus transmission started in the south of the district and later dispersed to the west, and finally arrived in the east. Different transmission routes among the studied herds, such as non-replicating vectors and close contact contagion (i.e., aerosols), may be responsible for viral spread.

Construction and characterization of recombinant senecavirus A expressing secreted luciferase for antiviral screening.

Senecavirus A (SVA) is a newly identified picornavirus associated with swine vesicular disease and neonatal mortality. The development of an SVA incorporating an exogenous reporter gene provides a powerful tool for viral research. In this study, we successfully constructed a recombinant SVA expressing Gaussia Luciferase (Gluc), termed rSVA-Gluc. The growth kinetics of rSVA-Gluc in BHK-21 cells were found to be comparable to those of the parental virus, and Gluc activity paralleled the virus growth curve. Genetic analysis revealed stable inheritance of the inserted reporter protein genes for at least six generations. We evaluated the utility of rSVA-Gluc in antiviral drug screening, and the results highlighted its potential as an effective tool for such purposes against SVA. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available on request from the corresponding author.

Use of FTA card for the detection of two RNA (CSFV and SV-A) and two DNA viruses (ASFVand SuHV-1) of importance in veterinary medicine.

The FTA card has emerged as a promising alternative for nucleic acid extraction. The FTA card is a filter paper impregnated with chemicals that preserve and stabilize the genetic material present in the sample, allowing for its storage and transport at room temperature. The aim of this study was to test the card for the detection of RNA and DNA nucleic acids. Two RNA viruses (Senecavirus A and classical swine fever virus) and two DNA viruses (African swine fever virus and suid alphaherpesvirus 1) were tested, and in all cases, there was a decrease in sensitivity. The methods exhibited good repeatability and demonstrated a rapid and practical use for sample transport and nucleic acid extraction.

Multiple functions of the nonstructural protein 3D in picornavirus infection.

3D polymerase, also known as RNA-dependent RNA polymerase, is encoded by all known picornaviruses, and their structures are highly conserved. In the process of picornavirus replication, 3D polymerase facilitates the assembly of replication complexes and directly catalyzes the synthesis of viral RNA. The nuclear localization signal carried by picornavirus 3D polymerase, combined with its ability to interact with other viral proteins, viral RNA and cellular proteins, indicate that its noncatalytic role is equally important in viral infections. Recent studies have shown that 3D polymerase has multiple effects on host cell biological functions, including inducing cell cycle arrest, regulating host cell translation, inducing autophagy, evading immune responses, and triggering inflammasome formation. Thus, 3D polymerase would be a very valuable target for the development of antiviral therapies. This review summarizes current studies on the structure of 3D polymerase and its regulation of host cell responses, thereby improving the understanding of picornavirus-mediated pathogenesis caused by 3D polymerase.

circRNA_8521 promotes Senecavirus A infection by sponging miRNA-324 to regulate LC3A.

Senecavirus A (SVA) causes outbreaks of vesicular disease in pigs, which imposes a considerable economic burden on the pork industry. As current SVA prevention measures are ineffective, new strategies for controlling SVA are urgently needed. Circular (circ)RNA is a newly characterized class of widely expressed, endogenous regulatory RNAs, which have been implicated in viral infection; however, whether circRNAs regulate SVA infection remains unknown. To investigate the influence of circRNAs on SVA infection in porcine kidney 15 (PK-15) cells, RNA sequencing technology was used to analyze the circRNA expression profiles of SVA-infected and uninfected PK-15 cells, the interactions between circRNAs, miRNAs, and mRNAs potentially implicated in SVA infection were predicted using bioinformatics tools. The prediction accuracy was verified using quantitative real-time (qRT)-PCR, Western blotting, as well as dual-luciferase reporter and RNA pull-down assays. The results showed that 67 circRNAs were differentially expressed as a result of SVA infection. We found that circ_8521 was significantly upregulated in SVA-infected PK-15 cells and promoted SVA infection. circ_8521 interacted with miR-324. miR-324 bound to LC3A mRNA which inhibited the expression of LC3A. Knockdown of LC3A inhibited SVA infection. However, circ_8521 promoted the expression of LC3A by binding to miR-324, thereby promoting SVA infection. We demonstrated that circ_8521 functioned as an endogenous miR-324 sponge to sequester miR-324, which promoted LC3A expression and ultimately SVA infection.

Genomic profile of eGFP-tagged senecavirus A subjected to serial plaque-to-plaque transfers.

Senecavirus A (SVA) belongs to the genus Senecavirus in the family Picornaviridae. This virus possesses a positive-sense, single-stranded RNA genome, approximately 7200 nt in length, composed of a single 5' untranslated region, encoding region and 3' untranslated region. In this study, a recombinant SVA tagged with enhanced green fluorescent protein (eGFP) sequence, rSVA-eGFP, was rescued from its cDNA clone using reverse genetics. The passage-5 (P5) rSVA-eGFP was totally subjected to 55 rounds of consecutive fluorescent plaque-to-fluorescent plaque (FP-FP) transfers, and one extra common passaging in vitro. The P61 viral stock was analyzed by next-generation sequencing. The result showed ten single-nucleotide mutations (SNMs) in the rSVA-eGFP genome, including nine transitions and only one transversion. The P61 progeny still showed a complete eGFP sequence, indicating no occurrence of copy-choice recombination within the eGFP region during serial FP-FP transfers. In other words, this progeny was genetically deficient in the recombination of eGFP sequence (RES), namely, an RES-deficient strain. Out of ten SNMs, three were missense mutations, leading to single-amino acid mutations (SAAMs): F15V in L protein, A74T in VP2, and E53R in 3D protein. The E53R was predicted to be spatially adjacent to the RNA channel of 3D protein, perhaps involved in the emergence of RES-deficient strain. In conclusion, this study uncovered a global landscape of rSVA-eGFP genome after serial FP-FP transfers, and moreover shed light on a putative SAAM possibly related to the RES-deficient mechanism.

Picornavirus security proteins promote the release of extracellular vesicle enclosed viruses via the modulation of host kinases.

The discovery that extracellular vesicles (EVs) serve as carriers of virus particles calls for a reevaluation of the release strategies of non-enveloped viruses. Little is currently known about the molecular mechanisms that determine the release and composition of EVs produced by virus-infected cells, as well as conservation of these mechanisms among viruses. We previously described an important role for the Leader protein of the picornavirus encephalomyocarditis virus (EMCV) in the induction of virus-carrying EV subsets with distinct molecular and physical properties. EMCV L acts as a 'viral security protein' by suppressing host antiviral stress and type-I interferon (IFN) responses. Here, we tested the ability of functionally related picornavirus proteins of Theilers murine encephalitis virus (TMEV L), Saffold virus (SAFV L), and coxsackievirus B3 (CVB3 2Apro), to rescue EV and EV-enclosed virus release when introduced in Leader-deficient EMCV. We show that all viral security proteins tested were able to promote virus packaging in EVs, but that only the expression of EMCV L and CVB3 2Apro increased overall EV production. We provide evidence that one of the main antiviral pathways counteracted by this class of picornaviral proteins, i.e. the inhibition of PKR-mediated stress responses, affected EV and EV-enclosed virus release during infection. Moreover, we show that the enhanced capacity of the viral proteins EMCV L and CVB3 2Apro to promote EV-enclosed virus release is linked to their ability to simultaneously promote the activation of the stress kinase P38 MAPK. Taken together, we demonstrate that cellular stress pathways involving the kinases PKR and P38 are modulated by the activity of non-structural viral proteins to increase the release EV-enclosed viruses during picornavirus infections. These data shed new light on the molecular regulation of EV production in response to virus infection.

Modulation of nucleotide metabolism by picornaviruses.

Viruses actively reprogram the metabolism of the host to ensure the availability of sufficient building blocks for virus replication and spreading. However, relatively little is known about how picornaviruses-a large family of small, non-enveloped positive-strand RNA viruses-modulate cellular metabolism for their own benefit. Here, we studied the modulation of host metabolism by coxsackievirus B3 (CVB3), a member of the enterovirus genus, and encephalomyocarditis virus (EMCV), a member of the cardiovirus genus, using steady-state as well as 13C-glucose tracing metabolomics. We demonstrate that both CVB3 and EMCV increase the levels of pyrimidine and purine metabolites and provide evidence that this increase is mediated through degradation of nucleic acids and nucleotide recycling, rather than upregulation of de novo synthesis. Finally, by integrating our metabolomics data with a previously acquired phosphoproteomics dataset of CVB3-infected cells, we identify alterations in phosphorylation status of key enzymes involved in nucleotide metabolism, providing insight into the regulation of nucleotide metabolism during infection.

Picornavirus 2C proteins: structure-function relationships and interactions with host factors.

Picornaviruses, which are positive-stranded, non-enveloped RNA viruses, are known to infect people and animals with a broad spectrum of diseases. Among the nonstructural proteins in picornaviruses, 2C proteins are highly conserved and exhibit multiple structural domains, including amphipathic α-helices, an ATPase structural domain, and a zinc finger structural domain. This review offers a comprehensive overview of the functional structures of picornaviruses' 2C protein. We summarize the mechanisms by which the 2C protein enhances viral replication. 2C protein interacts with various host factors to form the replication complex, ultimately promoting viral replication. We review the mechanisms through which picornaviruses' 2C proteins interact with the NF-κB, RIG-I, MDA5, NOD2, and IFN pathways, contributing to the evasion of the antiviral innate immune response. Additionally, we provide an overview of broad-spectrum antiviral drugs for treating various enterovirus infections, such as guanidine hydrochloride, fluoxetine, and dibucaine derivatives. These drugs may exert their inhibitory effects on viral infections by targeting interactions with 2C proteins. The review underscores the need for further research to elucidate the precise mechanisms of action of 2C proteins and to identify additional host factors for potential therapeutic intervention. Overall, this review contributes to a deeper understanding of picornaviruses and offers insights into the antiviral strategies against these significant viral pathogens.

Co-infecting viruses of species Bovine rhinitis B virus (Picornaviridae) and Bovine nidovirus 1 (Tobaniviridae) identified for the first time from a post-mortem respiratory sample of a sheep (Ovis aries) in Hungary.

In this study, a picornavirus and a nidovirus were identified from a single available nasopharyngeal swab (NPS) sample of a freshly deceased sheep, as the only vertebrate viruses found with viral metagenomics and next-generation sequencing methods. The sample was originated from a mixed feedlot farm in Hungary where sheep and cattle were held together but in separate stalls. Most of the sheep had respiratory signs (coughing and increased respiratory effort) at the time of sampling. Other NPS were not, but additional enteric samples were collected from sheep (n = 27) and cattle (n = 11) of the same farm at that time. The complete/nearly complete genomes of the identified viruses were determined using RT-PCR and Nanopore (MinION-Flonge) / Dye-terminator sequencing techniques. The results of detailed genomic and phylogenetic analyses indicate that the identified picornavirus most likely belongs to a type 4 genotype of species Bovine rhinitis B virus (BRBV-4, OR885914) of genus Aphthovirus, family Picornaviridae while the ovine nidovirus (OvNV, OR885915) - as a novel variant - could belong to the recently created Bovine nidovirus 1 (BoNV) species of genus Bostovirus, family Tobaniviridae. None of the identified viruses were detectable in the enteric samples using RT-PCR and generic screening primer pairs. Both viruses are well-known respiratory pathogens of cattle, but their presence was not demonstrated before in other animals, like sheep. Furthermore, neither BRBV-4 nor BoNVs were investigated in European cattle and/or sheep flocks, therefore it cannot be determined whether the presence of these viruses in sheep was a result of a single host species switch/spillover event or these viruses are circulating in not just cattle but sheep populations as well. Further studies required to investigate the spread of these viruses in Hungarian and European sheep and cattle populations and to identify their pathogenic potential in sheep.

IFITM1 and IFITM2 inhibit the replication of senecavirus A by positive feedback with RIG-I signaling pathway.

The role of host factors in the replication of emerging senecavirus A (SVA) which induced porcine idiopathic vesicular disease (PIVD) distributed worldwide remains obscure. Here, interferon-induced transmembrane (IFITM) protein 1 and 2 inhibit SVA replication by positive feedback with RIG-I signaling pathway was reported. The expression levels of IFITM1 and IFITM2 increased significantly in SVA infected 3D4/21 cells. Infection experiments of cells with over and interference expression of IFITM1 and IFITM2 showed that these two proteins inhibit SVA replication by regulating the expression of interferon beta (IFN-ß), IFN-stimulated gene 15 (ISG-15), interleukin 6 (IL-6), IL-8, tumor necrosis factor alpha (TNF-α), IFN regulatory factor-3 (IRF3), and IRF7. Further results showed that antiviral responses of IFITM1 and IFITM2 were achieved by activating retinoic acid-inducible gene I (RIG-I) signaling pathway which in turn enhanced the expression of IFITM1 and IFITM2. It is noteworthy that conserved domains of these two proteins also paly the similar role. These findings provide new data on the role of host factors in infection and replication of SVA and help to develop new agents against the virus.

Adjuvant screening of the Senecavirus A inactivated vaccine in mice and evaluation of its immunogenicity in pigs.

BACKGROUND: Senecavirus A (SVA) causes an emerging vesicular disease (VD) with clinical symptoms indistinguishable from other vesicular diseases, including vesicular stomatitis (VS), foot-and-mouth disease (FMD), and swine vesicular disease (SVD). Currently, SVA outbreaks have been reported in Canada, the U.S.A, Brazil, Thailand, Vietnam, Colombia, and China. Based on the experience of prevention and control of FMDV, vaccines are the best means to prevent SVA transmission. RESULTS: After preparing an SVA inactivated vaccine (CH-GX-01-2019), we evaluated the immunogenicity of the SVA inactivated vaccine mixed with Imject® Alum (SVA + AL) or Montanide ISA 201 (SVA + 201) adjuvant in mice, as well as the immunogenicity of the SVA inactivated vaccine combined with Montanide ISA 201 adjuvant in post-weaned pigs. The results of the mouse experiment showed that the immune effects in the SVA + 201 group were superior to that in the SVA + AL group. Results from pigs immunized with SVA inactivated vaccine combined with Montanide ISA 201 showed that the immune effects were largely consistent between the SVA-H group (200 µg) and SVA-L group (50 µg); the viral load in tissues and blood was significantly reduced and no clinical symptoms occurred in the vaccinated pigs. CONCLUSIONS: Montanide ISA 201 is a better adjuvant choice than the Imject® Alum adjuvant in the SVA inactivated vaccine preparation, and the CH-GX-01-2019 SVA inactivated vaccine can provide effective protection for pigs.

Assessment of Kinome-Wide Activity Remodeling upon Picornavirus Infection.

Picornaviridae represent a large family of single-stranded positive RNA viruses of which different members can infect both humans and animals. These include the enteroviruses (e.g., poliovirus, coxsackievirus, and rhinoviruses) as well as the cardioviruses (e.g., encephalomyocarditis virus). Picornaviruses have evolved to interact with, use, and/or evade cellular host systems to create the optimal environment for replication and spreading. It is known that viruses modify kinase activity during infection, but a proteome-wide overview of the (de)regulation of cellular kinases during picornavirus infection is lacking. To study the kinase activity landscape during picornavirus infection, we here applied dedicated targeted mass spectrometry-based assays covering ∼40% of the human kinome. Our data show that upon infection, kinases of the MAPK pathways become activated (e.g., ERK1/2, RSK1/2, JNK1/2/3, and p38), while kinases involved in regulating the cell cycle (e.g., CDK1/2, GWL, and DYRK3) become inactivated. Additionally, we observed the activation of CHK2, an important kinase involved in the DNA damage response. Using pharmacological kinase inhibitors, we demonstrate that several of these activated kinases are essential for the replication of encephalomyocarditis virus. Altogether, the data provide a quantitative understanding of the regulation of kinome activity induced by picornavirus infection, providing a resource important for developing novel antiviral therapeutic interventions.