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To study the outcome of natural selection using phylogenetic trees, we analyzed full-length genome sequences of porcine teschovirus (PTV). PTV belongs to the family Picornaviridae and has a positive-stranded RNA genome, the replication of which is carried out by the error-prone viral RNA-dependent RNA polymerase. The viral RNA encodes a single polyprotein that is cleaved into structural (i.e., L, VP4, VP2, VP3 and VP1) and nonstructural proteins (i.e., 2A, 2B, 2C, 3A, 3B, and 3C). A high degree of genetic diversity was found based on the pairwise nucleotide distances and on the mean ratio of the number of nonsynonymous (dN) and synonymous (dS) substitutions (dN/dS) in the structural genes. Conversely, the diversity of the nonstructural genes was lower. The differences in genetic diversity between the structural and nonstructural genomic regions were likely due to strong purifying selection; consequently, the estimates of phylogenies were also discordant among these genes. In particular, maximum-likelihood and Bayesian methods generated short-branched trees when loci that are under strong purifying selection were used. These findings indicate that even in an RNA virus with an intrinsically high mutation rate, a strong purifying selection will curb genetic diversity and should be considered an important source of bias in future studies based on phylogenetic methods. [ABSTRACT FROM AUTHOR]

A porcine teschovirus (PTV) was isolated from a dead piglet from a herd of 200 sows showing reproductive failure in Fuyu, Heilongjiang Province, China. Sequencing of most of the genome of this isolate, designated Fuyu/2009, revealed that is was a PTV-8 isolate, closely related to a previously identified Chinese PTV-8 strain (Jilin/2003). Both Chinese strains vary from the European PTV-8 strains by different clustering of the 3CD sequences. Infection with these viruses may be associated with pronounced diseases. [ABSTRACT FROM AUTHOR]

Abstract: A colloid gold strip (CGS) test for detecting antibodies to H5 subtype Avian Influenza Virus (AIV) was developed. The test is based on membrane chromatography and uses colloidal gold conjugated with inactivated AIV-H5N1 as the tracer. On the test strip, a baculovirus expressed haemagglutinin (HA) protein was used as the capture complex at the “test line”, and anti-HA monoclonal antibody was used as the capture antibody at the “control line”. The assembled test strip was housed in a plastic case. Compared with the hemagglutination inhibition test, the sensitivity and specificity of the CGS test were 88.8% and 97.6%, respectively, in detecting H5N1 antibodies in 830 serum samples from vaccinated chickens. Because it is rapid and does not require specialized equipment or technicians, the CGS test should be useful for detecting H5N1 antibodies in the field. [Copyright &y& Elsevier]

Abstract: Porcine reproductive and respiratory syndrome is rapidly gaining worldwide importance as one of the most economically significant diseases of swine. The antibody of Porcine reproductive and respiratory syndrome virus (PRRSV) is detected currently by the combined use of an enzyme-linked immunosorbent assay, serum neutralization test, immunoperoxidase monolayer assay, indirect immunofluorescent antibody test. These methods are time-consuming and require specialized equipment operated by trained technicians. The purpose of this study was to evaluate a simple strip assay (based on a chromatographic and immunogold system) for specific detection of PRRSV antibody in swine sera. This “immunochromatographic strip” test uses Escherichia coli-expressed viral recombinant membrane protein antigen in combination with recombinant nucleocapsid protein as capture protein for detecting antibodies against PRRSV. In this study, the performance of this assay was evaluated with sera from both clinical samples and experimentally infected piglets. Detection by immunochromatographic strip test was compared with detection by a standard, available commercially, indirect enzyme-linked immunosorbent assay and an immunoperoxidase monolayer assay. The immunochromatographic test strip detected antibodies in sera known to contain antibodies to PRRSV in 95.7% sensitivity of samples from pigs infected experimentally and 98.6% sensitivity of clinical serum samples. For sera that did not contain antibodies to PRRSV, the specificity was 97.8% and 98.2% for clinical and experimental serum samples, respectively. [Copyright &y& Elsevier]

Abstract: Encephalomyocarditis virus (EMCV) can cause myocarditis, respiratory failure, reproductive failure, and mortality in pregnant sows, fetuses, and ablactating piglets. Diseases caused by EMCV currently affect the swine industry worldwide. A virus was isolated from organs of dead piglets that presented with acute myocarditis in northern China. The production of a specific cytopathic effect on susceptible cells and the results of hemagglutination inhibition (HI) assay, PCR, electron microscopy (EM), and sequencing indicated that the pathogen was EMCV; the strain was named HB10. Other pathogenic agents causing myocarditis and death were excluded as possible pathogenic agents. Phylogenetic analyses of the capsid coding region and the VP3/VP1 genes using the neighbour-joining method revealed that EMCV isolates cluster into two groups (groups 1 and 2) with two sub-clusters within group 1 (group 1a and b). HB10 belongs to group 1a, along with strains CBNU, GX0601, BJC3, NJ08, and BEL-2887A/91. Five strains isolated from Sus scrofa belong to group 2. The results of this and previous studies indicate that HB10 and other EMCV strains cause myocarditis of pigs in China. [Copyright &y& Elsevier]

Pigeon paramyxovirus-1 (PPMV-1) is a strain of Newcastle disease virus (NDV) that has adapted to infect pigeons and poses a constant threat to the commercial poultry industry. Early detection via rapid and sensitive methods, along with timely preventative and mitigating actions, is important for reducing the spread of PPMV-1. Here, we report the development of a TaqMan loop-mediated isothermal amplification assay (TaqMan-LAMP) for rapid and specific detection of PPMV-1 based on the F gene. This system makes use of six novel primers and a TaqMan probe that targets nine distinct regions of the F gene that are highly conserved among PPMV-1 isolates. The results showed that the limit of detection was 10 copies μL-1 for PPMV-1 cDNA and 0.1 ng for PPMV-1 RNA. The reaction was completed within 25 min and was thus faster than conventional RT-PCR. Moreover, no cross-reactions with similar viruses or with peste des petits ruminants virus (PPRV) or NDV LaSota vaccine strains were observed under the same conditions. To evaluate the applicability of the assay, the TaqMan-LAMP assay and a commercial RT-PCR assay were compared using 108 clinical samples, and the concordance rate between two methods was found to be 96.3%. The newly developed PPMV-1 TaqMan-LAMP assay can therefore be used for simple, efficient, rapid, specific, and sensitive diagnosis of PPMV-1 infections. [ABSTRACT FROM AUTHOR]

COVID‐19 is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). It has rapidly spread to 216 countries and territories since first outbreak in December of 2019, posing a substantial economic losses and extraordinary threats to the public health worldwide. Although bats have been suggested as the natural host of SARS‐CoV‐2, transmission chains of this virus, role of animals during cross‐species transmission, and future concerns remain unclear. Diverse animal coronaviruses have extensively been studied since the discovery of avian coronavirus in 1930s. The current article comprehensively reviews and discusses the current understanding about animal coronaviruses and SARS‐CoV‐2 for their emergence, transmission, zoonotic potential, alteration of tissue/host tropism, evolution, status of vaccines and surveillance. This study aims at providing guidance for control of COVID‐19 and preventative strategies for possible future outbreaks of zoonotic coronavirus via cross‐species transmission. [ABSTRACT FROM AUTHOR]

Pseudorabies virus (PRV), the causative agent of Aujeszky's disease, has gained increased attention in China in recent years as a result of a recent outbreak of pseudorabies. The causative agent has a wide spectrum of hosts, including pigs, cattle, sheep, dogs, cats, bats, bears, and even some avian species. Although dog-related cases of pseudorabies have been reported regularly, many cases are overlooked, and few PRV strains are isolated because death occurs rapidly after PRV infection and veterinarians often do not test for PRV in dogs. Here, we performed a retrospective detection of PRV in dogs from July 2017 to December 2018. We found that PRV (including gE-deleted strains, classical strains, and variant strains) is prevalent in dogs regardless of season and region and that the epidemic PRV strains in dogs share high sequence similarity with gC and gE genes of swine epidemic strains and commercial vaccine strains. Collectively, our findings underscore the importance of PRV surveillance in dogs, which is beneficial for understanding the epidemiology of PRV in dogs and assists in efforts aimed at effectively controlling this disease. [ABSTRACT FROM AUTHOR]

• The synthesized novel PPV vaccine (PPV/N-2-HACC) had good storage stability and high safety. • PPV/N-2-HACC elicited the effectually humoral immune responses and maintained higher antibody levels for a long time. • PPV/N-2-HACC vaccine protected sows from PPV challenge. • N-2-HACC is a safe, stable and effective adjuvants with the ability to enhance the immune responses of inactive immunogens. Porcine parvovirus (PPV) is one of the most common and important virus causes of infectious infertility in swine throughout the world. Inactivated PPV vaccine is broadly used, however, there is no appropriate immunomodulatory adjuvant for enhancing present vaccines and developing new ones. Therefore, in this study, the water-soluble N -2-Hydroxypropyl trimethyl ammonium chloride chitosan (N-2-HACC) was synthesized, the adjuvant potential of chitosan derivative was evaluated in inactivated PPV vaccine. Twenty adult healthy sows were assigned to four groups and vaccinated with synthesized PPV/N-2-HACC, commercial inactivated vaccine, N-2-HACC adjuvant and PBS. After insemination, all sows were challenged with the homologous PPV-H strain. In vivo immunization showed that sows immunized with the PPV/N-2-HACC induced more long-lasting HI antibodies and strong immune responses. Importantly, immunization of PPV/N-2-HACC significantly protected sows from homologous PPV-H strain infection. However, immunization of PPV/N-2-HACC didn't change the level of IL-2, IL-4 and IFN-γ and the production of CD4+, CD8 + T lymphocyte. The results indicated that PPV/N-2-HACC protect PPV infection mainly through enhancing the humoral immunity rather than cellular immunity. In addition, the mummified fetuses were observed from the control groups, but neither of the two vaccine groups. In conclusion, these results suggest that N-2-HACC can be exploited as an effective adjuvant for vaccine development, and the PPV/N-2-HACC are potent immunization candidates against PPV infection. [ABSTRACT FROM AUTHOR]

• A completely attenuated viral population was produced by long-term passaging of duck TMUV in BHK-21 cells. • A single-dose vaccination of JXSP-P310 can provide efficient protection for ducks against a virulent TMUV challenge. • Multiple gene mutations co-contribute to the complete attenuation of TMUV. • JXSP-310P is a promising live vaccine candidate against duck TMUV infection. Duck Tembusu virus (TMUV) is an emerging pathogenic flavivirus that causes severe egg-drop and fatal encephalitis in domestic ducks and geese. Although a live-attenuated virus vaccine is effective for disease control, the stability of the attenuation has not been clearly evaluated due to a poor understanding of the attenuation mechanism. Here, a virulent duck TMUV isolate was successively passaged in BHK-21 cells, leading to an approximately 100-fold increase of virus production in cell culture and a complete attenuation of virulence for ducks. The passaged virus induced high titers of TMUV-specific antibody and provided efficient protection against a virulent TMUV challenge after a single-dose vaccination. One hundred and two, and eighteen single-nucleotide polymorphisms (SNPs) at a frequency of >1% were respectively identified in the attenuated virus population and the original isolate by deep sequencing. The increased SNPs numbers suggested that the accumulated variants of virus population may have conferred the phenotypic changes. We cloned and characterized a dominant variant exhibiting similar fitness to the mixed population, and 23 amino acid substitutions were identified across the viral open reading frame. Using reverse genetics, two chimeric viruses were generated by introducing the mutated E or NS5 gene into the backbone of virulent TMUV. We found that mutations in the E gene conferred a fitness advantage in BHK-21 cells and decreased the virus pathogenicity, whereas NS5 mutations reduced the virus infectivity in ducklings without altering the in vitro fitness. In conclusion, increased mutations in a virulent TMUV strain did substantially reduce the virus virulence, and mutations in multiple genes co-contribute to TMUV attenuation. [ABSTRACT FROM AUTHOR]

Protoparvoviruses, widespread among cats and wild animals, are responsible for leukopenia. Feline panleukopenia virus (FPLV) in domestic cats is genetically diverse and some strains may differ from those used for vaccination. The presence of FPLV in two domestic cats from Hebei Province in China was identified by polymerase chain reaction. Samples from these animals were used to isolate FPLV strains in CRFK cells for genome sequencing. Phylogenetic analysis was performed to compare our isolates with available sequences of FPLV, mink parvovirus (MEV) and canine parvovirus (CPV). The isolated strains were closely related to strains of FPLV/MEV isolated in the 1960s. Our analysis also revealed that the evolutionary history of FPLV and MEV is characterized by local adaptations in the Vp2 gene. Thus, it is likely that new FPLV strains are emerging to evade the anti-FPLV immune response. [ABSTRACT FROM AUTHOR]

Background: Bovine viral diarrhoea virus (BVDV) is the member of the genus Pestivirus within the Flaviviridae family and responsible for severe economic losses in the cattle industry. BVDV can employ 'infect-and-persist' strategy and 'hit-and-run' strategy to remain associated with hosts and thus contributes to BVDV circulation in cattle herds. BVDV have also evolved various strategies to evade the innate immunity of host. To further understand the mechanisms by which BVDV overcomes the host cell innate immune response and provide more clues for further understanding the BVDV-host interaction, in this descriptive study, we conducted a investigation of differentially expressed genes (DEGs) of the host during BVDV infection by RNA-Seq analysis. Results: Our analysis identified 1297, 1732, 3072, and 1877 DEGs in the comparison groups mock vs. MDBK cells infected with BVDV post 2 h (MBV2h), mock vs. MBV6h, mock vs. MBV12h, and mock vs. MBV24h, respectively. The reproducibility and repeatability of the results were validated by RT-qPCR. Enrichment analyses of GO annotations and KEGG pathways revealed the host DEGs that are potentially induced by BVDV infection and may participate in BVDV-host interactions. Protein-protein interaction (PPI) network analyses identified the potential interactions among the DEGs. Our findings suggested that BVDV infection induced the upregulation of genes involved in lipid metabolism. The expression of genes that have antiviral roles, including ISG15, Mx1, OSA1Y, were found to be downregulated and are thus potentially associated with the inhibition of host innate immune system during BVDV infection. The expression levels of F3, C1R, KNG1, CLU, C3, FB, SERPINA5, SERPINE1, C1S, F2RL2, and C2, which belong to the complement and coagulation signalling cascades, were downregulated during BVDV infection, which suggested that the complement system might play a crucial role during BVDV infection. Conclusion: In this descriptive study, our findings revealed the changes in the host transcriptome expression profile during BVDV infection and suggested that BVDV-infection induced altering the host's metabolic network, the inhibition of the expression of antiviral proteins and genes within the complement system might be contributed to BVDV proliferation. The above findings provided unique insights for further studies on the mechanisms underlying BVDV-host interactions. [ABSTRACT FROM AUTHOR]

• cVLPs displaying the B cell epitope of PPV1 around the surface of the two-fold axes of PCV2 VLPs was successfully prepared. • cVLPs conferred more effective immune protection (based on viral load) than a commercial PCV2 vaccine in guinea pigs. • cVLPs vaccinated guinea pigs had some protective immunity against challenge with PPV. Although PCV2 infections generally cause mild disease in pigs, concurrent co-infections with other pathogens can damage the immune system and cause more severe diseases, collectively termed porcine circovirus associated diseases (PCVAD). Involvement of porcine parvovirus (PPV, a common cause of reproductive failure in naïve dams) in PCVAD caused by PCV2, has been reported. As this co-infection can be difficult to eliminate, there is a critical need to develop an effective vaccine to protect against PPV or synergistic effects of PCV2 and PPV under field conditions. In this study, we designed chimeric PCV2 virus-like particles (cVLPs) displaying a B-cell epitope derived from PPV1 structural protein around the surface of the 2-fold axes of PCV2 VLPs, based on 3D-structure analysis of the PCV2 capsid. The cVLPs were successfully prepared, verified by transmission electron microscopy and chromatography, with robust antibody titers against PCV2 and PPV1 produced in mice and guinea pigs. In addition, in guinea pigs challenged with 106 TCID 50 PCV2, cVLPs conferred more effective immune protection (based on viral load) than a commercial PCV2 vaccine. Finally, antibody responses and immune protection against PPV were also evaluated. In guinea pigs vaccinated with cVLPs, although PPV antibodies detected by a hemagglutination inhibition (HI) assay appeared later after vaccination in the PCV2 cVLPs group than in the commercial PPV vaccine group, there were fewer PPV genomic DNA copies in the PCV2 cVLPs group than in a PBS group. In conclusion, guinea pigs vaccinated with cVLPs developed effective protective immunity against PCV2 challenge, with some protective immunity against PPV. This study provided valuable research data to pursue molecular design of chimeric epitopes PCV2 VLPs. [ABSTRACT FROM AUTHOR]

In this study, we describe a novel and rapid method for the construction of a full-length infectious clone (pPPV). The constructed clone contained an engineered EcoRv site that served as a genetic marker and was shown to be infectious when transfected into a monolayer of PK-15 cells. The rescued virus (rPPV) of the infectious clone was found to be indistinguishable from wild-type virus BQ in terms of its biological properties. The generation of this PPV infectious clone provides a potentially powerful tool with which to elucidate the molecular pathogenesis of PPV. [ABSTRACT FROM AUTHOR]

Abstract Senecavirus A (SVA), which is associated with porcine vesicular disease and high mortality in neonatal piglets, is a small non-enveloped RNA virus and a member of Picornaviridae family. An emerging SVA strain, named SVA CH/FuJ/2017, was isolated from vesicular liquid and vesicular lesion tissue from piglets with vesicular disease in Fujian province, China. In our study, the complete genome sequence of SVA CH/FuJ/2017 strain has been determined. The viral genome was 7285 nt in length. The homology analysis indicated that the gene sequences of polyprotein and VP1 in SVA CH/FuJ/2017 shared highest nucleotide identities with American SVA isolates; and polyprotein showed the highest similarity with American SVA isolates. The phylogenetic analysis based on polyprotein and VP1 nucleotide sequences indicated that SVA CH/FuJ/2017 was closely related to American SVA isolates. The results revealed that the novel SVA strain was closely related to those SVA strains that were isolated in America. Hence, the retrospective study is important for tracing the probable origin of China SVA strains. Highlights • An emerging SVA strain, CH/FuJ/2017, was isolated from a pig herd with vesicular disease. • The phylogenetic analysis based on polyprotein and VP1 nucleotide sequences showed SVA CH/FuJ/2017 was closely related to American SVA isolates. • Our study suggested that it is possible that the spread of SVA might be related to the trade of pigs. [ABSTRACT FROM AUTHOR]

The one-step polymerase chain reaction (one-step PCR) detection assay is an innovative PCR detection method, eliminating nucleic acid extraction steps, in which samples can be directly added to PCR reagents for testing. For simultaneous detection of CDV and CCoV, a sensitive and specific one-step duplex PCR (one-step dPCR) assay was developed with two pairs of primers that were designed based on H and M gene sequences of CDV and CCoV, respectively. The one-step dPCR with optimized detection conditions has high specificity and sensitivity; independent sequencing assays further verified these results. [ABSTRACT FROM AUTHOR]

Abstract Foot-and-mouth disease virus (FMDV) is the causative agent of Foot-and-mouth disease (FMD), which is an acute and highly contagious disease affecting pigs, cattle and other cloven-hoofed animals. Several studies have shown that FMDV has evolved multiple strategies to evade the host innate immune response, but the underlying mechanisms for immune evasion are still not fully understood. In the current research, we have demonstrated that FMDV utilizes its non-structural protein 2B to sabotage the host immune response. Over-expression of the FMDV 2B inhibited Poly(I:C)-induced or SeV-triggered up-regulation of IFN-β, IL-6 as well as ISG15. When HEK293T cells were transfected with FMDV 2B, the phosphorylation of TBK1 and IRF3 was inhibited. Co-immunoprecipitation and pull-down experiments indicated that FMDV 2B protein could interact with host RIG-I and MDA5. Moreover, FMDV 2B also inhibited the expression of the RIG-I and MDA5. Thus, FMDV 2B negatively regulates the RLR-mediated IFN-β induction by targeting RIG-I and MDA5. Highlights • FMDV 2B is a negatively regulator of type I interferon induction. • FMDV 2B can inhibit the phosphorylation of TBK1 and IRF3. • FMDV 2B inhibited the expression of the RIG-I and MDA5. [ABSTRACT FROM AUTHOR]

Porcine circovirus 2 causes different clinical syndromes resulting in a significant economic loss in the pork industry and PCV3 infection was mainly distributed in the pig herds exhibiting PDNS and reproductive failure symptoms and was widely prevalent in the swine population in several states of the USA. Subsequently, PCV3 was also detected in the Chinese pig herds in Hubei and Shandong Provinces, etc. In a screening of 265 clinical samples from Beijing, Zhejiang, Guangdong and Hebei in China for PCV2, PCV3 and co-infection of PCV2 and PCV3, 14.2%, 16.6% and 6.8% of the samples tested positive, respectively. Under novel and optimized nano-dPCR reaction conditions, two specific fragments of 528 bp (PCV2) and 251 bp (PCV3) were amplified, respectively. No fragments were amplified when other porcine viruses were used as template. In this study, three PCV2 and three PCV3 isolates were evaluated by phylogenetic and alignment analysis and the results revealed that the PCV2 and PCV3 isolates appear new nucleotide substitutions and PCV3 isolates from China still included branch of porcine circovirus in USA. [ABSTRACT FROM AUTHOR]

Pathogenic strains of Aleutian mink disease virus (AMDV) such as Utah-1 do not replicate in cell culture (e.g., Crandell Rees feline kidney cells) while the in vitro- adapted AMDV strain ADV-Gorham (ADV-G) is not pathogenic. Here, we constructed a full-length infectious clone (pADV-G). Alignment of the VP2 gene of ADV-G with that of other AMDV strains revealed many amino acid (a.a.) residues conserved among pathogenic isolates that differed in ADV-G. Four virulence-associated, conserved residues of pADV-G VP2 were studied by site-directed mutagenesis (H92A, Q94S, Y115F, and I116L). Mutation of residue 92 or 94 decreased viral-transcription and viral-infectivity levels, whereas mutation of residue 115 or 116 did not affect viral-infectivity in CRFK cells. These results indicated that VP2 residues 92 and 94, both located on the surface of the viral capsid, are critical for AMDV infectivity in vitro . [ABSTRACT FROM AUTHOR]

Porcine parvovirus (PPV) is a pathogenic factor that primarily induces severe reproductive failure of pregnant swine, which results in extensive losses to the swine industry worldwide. In this study, a potential mechanism of PPV-induced activation of the nuclear transcription factor-kappaB (NF-κB) by infection in porcine kidney cells (PK-15) was elucidated for the first time. The subcellular localization of p65 analyzed by immunofluorescence assay (IFA) showed that PPV infection induced p65 translocation from the cytoplasm to the nucleus. p65 phosphorylation was detected in PK-15 cells with progression of PPV infection. NF-κB-regulated gene expression was enhanced in a viral dose-dependent manner using the NF-κB luciferase reporter assay system. Furthermore, PPV-induced NF-κB activation was closely related to the inhibitory kappa B alpha (IκBα) degradation. Treatment with a NF-κB-specific inhibitor demonstrated that the production of PPV progeny viruses was enhanced to some extent. In addition, these results demonstrated that the adapter molecule TIR domain-containing adapter inducing IFN-β (TRIF) and myeloid differentiation primary-response protein 88 (MyD88)-dependent signaling pathways were involved in PPV-induced NF-κB activation. Together, these results provide evidence that the toll-like receptor (TLR) pathway participates in recognition of PPV and induction of NF-κB activation, and add to understanding of the molecular mechanisms underlying PPV infection. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are vital post-transcriptional regulators that participate in host-pathogen interactions by modulating the expression of cellular factors. Previous studies have demonstrated that feline panleukopenia virus (FPV) alters miRNA expression levels within host cells. However, the relationship between FPV replication and host miRNAs remains unclear. Here, we demonstrated that FPV infection significantly altered cellular miR-92a-1–5p expression in F81 cells by upregulating the expression of specificity protein 1 (SP1). Furthermore, we observed that miR-92a-1–5p enhanced interferon (IFN-α/β) expression by targeting the suppressors of cytokine signaling 5 (SOCS5) that negatively regulates NF-κB signaling and inhibits FPV replication in host cells. These findings revealed that miR-92a-1–5p plays a crucial role in host defense against FPV infection. • FPV significantly altered miR-92a-1–5p expression in F81 cells by upregulating the expression of SP1. • SP1 is a vital transcriptional factor for miR-92a-1–5p expression. • MiR-92a-1–5p activated the NF-κB signaling pathway to promote IFN-I expression and inhibit FPV replication. [ABSTRACT FROM AUTHOR]

Objective To explore the adverse effect of roscovitine on reproductive system of male mice. Materials and methods Male hSOD1 G93A transgenetic mice received roscovitine 72 nmol/day (d) for 4 weeks (w), with normal control and dimethyl sulfoxide (DMSO)-treated animals served as controls ( n = 4). Male C57BL/6 mice were treated with roscovitine at either 72 nmol/d or 144 nmol/d for 4 w or 8 w, and normal control and DMSO treated mice served as controls. Fertility of male mice, sperm quality parameters, histological and related pathological changes of seminiferous tubules associated with roscovitine treatment were evaluated. Results In male hSOD1 G93A transgenetic mice treated with 72 nmol/d roscovitine for 4 w and C57BL/6 male mice treated with 72 nmol/d roscovitine for 8 w and 144 nmol/d roscovitine for 4 w and 8 w, sperm counts and sperm motility rates decreased and sperm abnormality rates increased, and damage of seminiferous tubules were detected. Roscovitine treatment induced inhibition of CDK5 activities and decrease of BrdU-positive tubuler cells. Conclusion These results demonstrated that roscovitine treatment induced interference of male reproductive system and caused impairment of fertilizing ability. Reproductive system of ALS male mice was more susceptible to roscovitine induced impaired fertilizing ability. [ABSTRACT FROM AUTHOR]

Astrocyte elevated gene-1 (AEG-1) has been reported to regulate the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and is also regulated by it. This study investigated how AEG-1 participates in the survival pathway of motor neurons in amyotrophic lateral sclerosis (ALS). We found reduced levels of AEG-1 in ALS motor neurons, both in vivo and in vitro, compared to wild type controls. Moreover, AEG-1 silencing demonstrated inhibition of the PI3K/Akt pathway and increased cell apoptosis. Additionally, the PI3K/Akt pathway in mSOD1 cells was unresponsive under serum deprivation conditions compared to wtSOD1 cells. These results suggest that AEG-1 deficiency, together with the inhibited PI3K/Akt pathway was associated with decreased viability of ALS motor neurons. However, the mRNA levels of AEG-1 were still lower in mSOD1 cells compared to the control groups, though the signaling pathway was activated by application of a PI3-K activator. This suggests that in ALS motor neurons, some unknown interruption exists in the PI3K/Akt/CREB/AEG-1 feedback loop, thus attenuating the protection by this signaling pathway. Together, these findings support that AEG-1 is a critical factor for cell survival, and the disrupted PI3K/Akt/CREB/AEG-1 cycle is involved in the death of injured motor neurons and pathogenesis of ALS. [ABSTRACT FROM AUTHOR]

Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for the simple, rapid, and specific amplification of DNA and has been used to detect viruses. A duplex nanoPCR molecular detection system was developed to detect pseudorabies virus (PRV) and porcine bocavirus (PBoV). Primers were selected to target conserved regions within the PRV gE gene and the PBoV NS1 gene. Under optimized nanoPCR reaction conditions, two specific fragments of 316 bp (PRV) and 996 bp (PBoV) were amplified by the duplex nanoPCR with a detection limit of 6 copies for PRV and 95 copies for PBoV; no fragments were amplified when other porcine viruses were used as template. When used to test 550 clinical samples, the duplex nanoPRC assay and a conventional duplex PCR assay provided very similar results (98.1% consistency); single PRV infections, single PBoV infections, and concurrent PRV and PBoV infections were detected in 37%, 15%, and 9% of the samples, respectively. The results indicate that the novel duplex nanoPCR assay is useful for the rapid detection of PRV and PBoV in pigs. [ABSTRACT FROM AUTHOR]

Highlights: [•] NanoPCR is a novel method for amplifying DNA; here a nanoPCR assay was developed to detect PBoV. [•] The nanoPCR assay was 100-fold more sensitive than a conventional PCR assay. [•] PBoV positive rate was 71.3% by PBoV nanoPCR which demonstrated PBoV is epidemic in China. [Copyright &y& Elsevier]

Highlights: [•] NanoPCR is a novel method for amplifying DNA. [•] A nanoPCR assay was developed to differentiate wild-type and gene-deleted PRV. [•] Primers were selected to amplify three PRV genes and to generate products of 431, 316, and 202bp.The nanoPCR assay was 100 to 1000-fold more sensitive than conventional PCR. [•] This is the first report of a nanoPCR assay for detection of a swine pathogen. [ABSTRACT FROM AUTHOR]

Highlights: [•] Porcine teschovirus (PTV) is widespread and increasing in swine herds in northeast of China. [•] Four serotypes (PTV-2, -4, -6, and -8) were detected. [•] Recombination among PTV serotypes has occurred evidently in the field. [•] PTV commonly occurs with other viruses of swine. [•] The relationship between PTV and disease is unclear. [ABSTRACT FROM AUTHOR]

Highlights: [•] Quantitative real-time PCR of 8 cytokines was established. [•] The established assays were highly specific and sensitive. [•] The transcriptive levels of mRNA of IFN-α, IFN-β, RIG-1 and IRF-7 were up-regulated. [•] The levels of TLR-9, IRF-3, JAK-1, JAK-2, STAT-1 and STAT-2 have barely changes. [ABSTRACT FROM AUTHOR]

Abstract: Porcine parvovirus (PPV) is a major causative agent of reproductive failure in swine, which currently affects the swine industry worldwide. Although PPV was identified several years ago, little is known about how it overcomes host innate immunity. In this study, we used quantitative real-time PCR and a luciferase reporter assay to determine whether PPV infection induces type I interferon (IFN-α and IFN-β) and whether PPV infection blocks dsRNA-induced IFN-β promoter activation in cell cultures. The results indicate that PPV does not induce type I interferon and that the NS2 protein of PPV could blocks dsRNA-induced IFN-β promoter activation. [Copyright &y& Elsevier]

Abstract: Newcastle disease virus (NDV) strains isolated from ostriches have been genotyped for the first time by partial sequencing of the F gene to determine the epidemiologic role that this species can play within ND outbreaks. Fifteen additional NDV strains, mostly isolated from chickens but also from pigeons and penguins, were also included in the study to determine genetic relationships with ostriches NDV isolates. High genetic diversity was demonstrated in ostrich NDV isolates, as the 10 isolates were grouped in four distinct NDV genotypes. In agreement with the results obtained when chicken isolates have been molecularly characterized, the predominant genotype in ostriches was the genotype VII. More interestingly, evidences of recombination between genotype II and VII were observed in one ostrich isolate and in two further chicken isolates. Therefore, it seems that ostriches may play a relevant role in the ecology and epidemiology of ND particularly in those regions where they have an increasing farming importance as minor poultry species. [Copyright &y& Elsevier]

Abstract: A multiplex RT-PCR (mRT-PCR) assay was developed and evaluated for its ability to detect multiple viral infections of swine simultaneously. One pair of primers was selected carefully for each of the following three RNA viruses: porcine reproductive and respiratory syndrome virus (PRRSV), classical swine fever virus (CSFV), and porcine teschovirus (PTV). Each target produced a specific amplicon with a size of 451bp (PRRSV), 343bp (CSFV), or 163bp (PTV). The sensitivity of the mRT-PCR using purified plasmid constructs containing the specific viral target fragments was 2.02×102, 2.90×103, and 6.16×103 copies for PRRSV, CSFV, and PTV, respectively. Among 69 clinical samples from Heilongjiang, Jilin, and Henan provinces, co-infection by PRRSV and CSFV was 4.4%, co-infection by PRRSV and PTV was 11.6%, co-infection by PTV and CSFV was 13.0%, and co-infection by the three viruses was 8.7%. In conclusion, the mRT-PCR should be useful for routine molecular diagnosis and epidemiology. [Copyright &y& Elsevier]

Abstract: To establish a reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method for rapid detection of infectious bursal disease virus (IBDV), four primers specific to six regions of the VP3 gene were designed; the VP3 region was selected because it is a conserved part of the IBDV genome. After amplification in an isothermal water bath for 70min, samples containing IBDV generated the expected ladder-like products while other viruses generated no product. The sensitivity and specificity of the RT-LAMP assay were evaluated by comparison with reverse-transcription polymerase chain reaction (RT-PCR) and virus isolation. The assay was significantly more sensitive than normal gel-based RT-PCR. Because it is specific and simple, the RT-LAMP assay can be widely applied in clinical laboratories for rapid detection of IBVD. [Copyright &y& Elsevier]

Simple Summary: The excessive or improper use of antibiotics in chicken feed has led to the emergence of antibiotic-resistant bacteria, drug residues in the tissue, and other relevant issues, and this situation is severe in China. From 31 December 2020, antibiotics were banned for use as supplemental growth promoters in animal feed in China; therefore, antibiotic substitutes are urgently needed in China. People are searching for ideal antibiotic alternatives, and probiotics have proven their potential use for this. Our current trial aims to evaluate the effects of the Bacillus subtilis (B. subtilis) YW1 strain on laying hens, including the effects on performance, morphology, cecal microbiota, and intestinal barrier function. Our study showed that orally administering laying hens with probiotic B. subtilis cannot significantly improve their overall egg production, can induce a healthier microbiota composition characterized by a higher ratio of beneficial bacteria, and strengthens the physical barrier function of the intestine by inducing a higher expression of the tight junction protein. This makes it a valid probiotic alternative to antibiotics, and also a reference strain for clinical application in the poultry industry. We investigated the efficacy of a single bacterium strain, Bacillus subtilis (B. subtilis) YW1, on the performance, morphology, cecal microbiota, and intestinal barrier function of laying hens. A total of 216 28-week-old Hy-line Brown laying hens were divided into three dietary treatment groups, with six replicates of 12 birds each for 4 weeks. The control group (Ctr) was fed a basal diet and the treatment groups, T1 and T2, were fed a basal diet supplemented with B. subtilis at a dose rate of 5 × 108 CFU/kg and 2.5 × 109 CFU/kg, respectively. Dietary supplementation with B. subtilis did not significantly affect overall egg production in both groups, with no obvious changes in average egg weight and intestine morphology. B. subtilis administration also improved the physical barrier function of the intestine by inducing significantly greater expression levels of the tight junction protein occludin in T1 (p = 0.07) and T2 (p < 0.05). Further, supplementation with B. subtilis effectively modulated the cecal microbiota, increasing the relative level of beneficial bacteria at the genus level (e.g., Bifidobacterium p < 0.05, Lactobacillus p = 0.298, Bacillus p = 0.550) and decreasing the level of potential pathogens (e.g., Fusobacterium p < 0.05, Staphylococcus p < 0.05, Campylobacter p = 0.298). Overall, B. subtilis YW1 supplementation cannot significantly improve the egg production; however, it modulated the cecal microbiota towards a healthier pattern and promoted the mRNA expression of the tight junction protein occludin in laying hens, making B. subtilis YW1 a good probiotic candidate for application in the poultry industry, and further expanding the resources of strains of animal probiotics. [ABSTRACT FROM AUTHOR]

• PRV contamination was widely distributed in the environment of pig farms. • Viral distribution in the environment is associated with the implementation of biosecurity measures. • PRV could transmit from pigs to dogs through virally contaminated fomites. Pseudorabies virus (PRV) is a zoonotic agent with a wide host range, causing significant economic losses in animal husbandry and potential public health risk globally. The causative agent has recently gained attention due to the inter-species transmission among different species of animals, even human beings. Although PRV's prevalence is found in many species of animals, regardless of whether the strain involved is a vaccine, classical or variant, few lines of evidence for the viral transmission route are available. Here, we reported that viral contamination is associated with the inter-species transmission of PRV. We found that PRV contamination was widely distributed in the environment of pig farms, that viral distribution in the environment is associated with the implementation of biosecurity measures, and that PRV could transmit from pigs to dogs through virally contaminated fomites. Collectively, our findings provide a basis for understanding the ecology and transmission route of PRV and underscore the importance of implementing biosecurity measures to control this disease. [ABSTRACT FROM AUTHOR]

• miR-1343-5p was upregulated in vitro and vivo in response to FPV-BJ04 strain infection. • Overexpression of miR-1343-5p promoted FPV-BJ04 strain replication. • miR-1343-5p inhibited type I interferon expression and PRDIII-I luciferase activity. Feline panleukopenia is an acute, highly contagious, and fatal infectious disease caused by feline panleukopenia virus (FPV) and has led to severe consequences on pets, economically important animals, and the wildlife industry. MicroRNAs (miRNAs) play significant roles in the host-pathogen interaction by modulating cellular factors expression which are essential for viral replication or host innate immune response to infection. However, the role of host miRNA response in FPV infection remains to be discovered. In this study, we screened nine host miRNAs associated with FPV infection that were previously implicated in innate immunity or antiviral functions. We found that miR-1343-5p overexpression strongly promoted FPV-BJ04 genomic DNA. Subsequently, the expression of host miR-1343-5p was upregulated by FPV-BJ04 infection in vitro and in vivo. In addition, we demonstrated that miR-1343-5p was a negative regulator of the IFN-I signaling pathway, thereby promoting FPV infection. Bioinformatic analysis combined with molecular biological assay indicated that interleukin-1 receptor-associated kinase 1 (IRAK1) is a putative target of miR-1343-5p. Collectively, our findings emphasize the importance of miR-1343-5p in host defense against FPV, thus, enhancing our understanding of its pathogenic mechanism. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play crucial roles in post-transcriptional regulation of gene expression in many biological processes. Feline panleukopenia virus (FPV) is a highly infectious pathogen that can cause severe disease in pets, economically important animals and wildlife. In this study, miRNAs associated with FPV infection were identified using high-throughput sequencing. Our results showed that 673 known miRNAs and 278 novel miRNAs were identified and 57 significantly differential expression miRNAs were found post-FPV infection in feline kidney cell line. Stem-loop qRT-PCR was applied to validate the expression of the randomly selected miRNAs; the results were consistent with the sequencing data. Furthermore, the target genes of differential expression miRNAs were analyzed and predicated by GO and KEGG pathway. Altogether, our analysis provides a potential link between miRNA expression and the pathogenesis of FPV infection. • MicroRNAs responses to FPV infection were identified in feline kidney cells by deep sequencing. • High-throughput sequencing revealed 673 known miRNAs and 278 novel miRNAs. • 57 miRNAs were significantly differentially expressed after FPV infection. • 15 randomly selected miRNAs were validated by stem-loop qRT-PCR. • Target genes of differential expression miRNAs were analyzed by GO and KEGG pathway. [ABSTRACT FROM AUTHOR]

Background: Live anticoccidial vaccines have been a tremendous success for disease prevention. The establishment of the reverse genetic manipulation platform has enabled the development of Eimeria parasites, the live anticoccidial vaccine strains, as vaccine vectors. In our previous study, recombinant E. tenella expressing a single immunodominant antigen of E. maxima (Et-EmIMP1) was able to protect chickens against challenge infection with E. maxima. This promising result encouraged us to further explore strategies to improve the protection efficacy of recombinant Eimeria and develop it as a vaccine vector. Results: We constructed a novel recombinant Eimeria line expressing apical membrane antigen 1 of E. maxima (Et-EmAMA1) and then immunized chickens with Et-EmAMA1 and/or Et-EmIMP1. We found that the E. maxima soluble antigen-specific cell-mediated immunity was much stronger in the birds that were co-immunized with Et-EmAMA1 and Et-EmIMP1 than in those that were immunized with Et-EmAMA1 or Et-EmIMP1 alone. The oocyst production after E. maxima infection was significantly reduced in the recombinant Eimeria-immunized birds compared with the wild-type-immunized and naïve birds. The oocyst production in the birds co-immunized with Et-EmAMA1 and Et-EmIMP1 was consistently the lowest among the treatment groups after E. maxima infection. Conclusions: These results demonstrated that Eimeria is an effective vaccine vector that can carry and deliver heterologous Eimeria antigens to the host immune system and trigger specific immune responses. Our results also suggested that increasing the number of recombinant Eimeria lines is an effective approach to enhance protective immunity against infections with heterologous pathogens. [ABSTRACT FROM AUTHOR]

Bovine parainfluenza virus type 3 (BPIV3) is one of the most important known viral respiratory pathogens of both young and adult cattle. It is also named "heat stress in transport", causing morbidity and mass death. New variants of BPIV3 have been detected or isolated in China since 2008. Here, we isolate one BPIV3 strain (named BPIV3 BJ) in Madin-Darby bovine kidney (MDBK) cells from nasal samples collected in China. Phylogenetic analysis showed that our isolate is related to BPIV3 of the genotype A. The comparison of BPIV3-BJ and the reference Chinese isolate NM09 showed that these strains are highly divergent. We found many differences in the amino acid composition in the nucleocapsid (NP) protein among these genotype A strains. Since the NP protein has been implicated in immunization studies, our BPIV3 isolate will be useful for the development of immune assays and vaccine studies. The diversity of BPIV3 lineages that we found in China indicated ongoing evolution for immune escape. Our study highlights the importance of genetic surveillance for determining the effect of BPIV3 variability on pathogen evolution and population-scale immunity. [ABSTRACT FROM AUTHOR]