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Foot-and-mouth disease virus (FMDV) causes an economically devastating disease of livestock that is controlled in endemic areas by vaccines containing intact inactivated FMDV particles. In this study, a novel monoclonal antibody named 5B6 has been identified and characterised, that permits the detection of all serotypes of FMDV via a conserved epitope near the N-terminus of the VP4 capsid protein. The antibody recognises intact virus particles known as 146S (the protective antigen) which contain VP4 and not dissociated capsids known as 12S (poorly protective antigen) which lack VP4. This allowed the development of a universal assay to specifically detect the protective antigen in vaccine samples using a simple ELISA. Such a test could be used to assess the quality of formulated vaccine following manufacture or prior to administration, or to assess unformulated vaccine antigen, and would be of great utility to enhance the effectiveness of FMD vaccination programmes.

Rhinoviruses (RVs) are the pathogens most often responsible for the common cold, and are a frequent cause of exacerbations in asthma, chronic obstructive pulmonary disease and cystic fibrosis. Here we report the discovery of IMP-1088, a picomolar dual inhibitor of the human N-myristoyltransferases NMT1 and NMT2, and use it to demonstrate that pharmacological inhibition of host-cell N-myristoylation rapidly and completely prevents rhinoviral replication without inducing cytotoxicity. The identification of cooperative binding between weak-binding fragments led to rapid inhibitor optimization through fragment reconstruction, structure-guided fragment linking and conformational control over linker geometry. We show that inhibition of the co-translational myristoylation of a specific virus-encoded protein (VP0) by IMP-1088 potently blocks a key step in viral capsid assembly, to deliver a low nanomolar antiviral activity against multiple RV strains, poliovirus and foot and-mouth disease virus, and protection of cells against virus-induced killing, highlighting the potential of host myristoylation as a drug target in picornaviral infections.

The research aims to study the effect of zinc oxide nanoparticles and Kevlar fibres on the absorption property of composite materials consisting of epoxy resins and phenol formaldehyde in different proportions. The results showed: Epoxy resins are not absorbed without adding phenol formaldehyde, which means an increase in the absorption property with an increases the proportion of phenol formaldehyde increases. The fibre strengthening also increases the absorption, so Kevlar with fibres gave the highest absorption; However, the absorption property decreases when the compounds are enhanced with zinc oxide nanoparticles as compared to the effects seen in the non-reinforced compounds.

IBDV is economically important to the poultry industry. Very virulent (vv) strains cause higher mortality rates than other strains for reasons that remain poorly understood. In order to provide more information on IBDV disease outcome, groups of chickens (n=18) were inoculated with the vv strain, UK661, or the classical strain, F52/70. Birds infected with UK661 had a lower survival rate (50%) compared to F52/70 (80%). There was no difference in peak viral replication in the bursa of Fabricius (BF), but the expression of chicken IFNβ, MX1 and IL-8 was significantly lower in the BF of birds infected with UK661 compared to F52/70 (p<0.05) as quantified by RTqPCR, and this trend was also observed in DT40 cells infected with UK661 or F52/70 (p<0.05). The induction of expression of type I IFN in DF-1 cells stimulated with polyI:C (measured by an IFN-β luciferase reporter assay) was significantly reduced in cells expressing ectopic VP4 from UK661 (p<0.05), but was higher in cells expressing ectopic VP4 from F52/70. Cells infected with a chimeric recombinant IBDV carrying the UK661-VP4 gene in the background of PBG98, an attenuated vaccine strain that induces high levels of innate responses (PBG98-VP4UK661) also showed a reduced level of IFNα and IL-8 compared to cells infected with a chimeric virus carrying the F52/70-VP4 gene (PBG98-VP4F52/70), and birds infected with PBG98-VP4UK661 also had a reduced expression of IFNα in the BF compared to birds infected with PBG98-VP4F52/70 . Taken together, these data demonstrate that UK661 induced the expression of lower levels of anti-viral type I IFN and proinflammatory genes than the classical strain in vitro and in vivo and this was, in part, due to strain-dependent differences in the VP4 protein.

Abstract Diagnostic tests for foot-and-mouth disease (FMD) include the detection of antibodies against either the viral non-structural proteins or the capsid. The detection of antibodies against the structural proteins (SP) of the capsid can be used to monitor seroconversion in both infected and vaccinated animals. However, SP tests need to be tailored to the individual FMD virus serotype and their sensitivity performances may be affected by antigenic variability within each serotype and mismatching between tests reagents. As a consequence, FMD Reference Laboratories need to maintain contingency to employ multiple type-specific assays for large-scale serological surveillance and post-vaccination monitoring in the event of FMD outbreaks. In this study, a highly conserved region in the N terminus of FMDV capsid protein VP2 (VP2N) was characterised using a panel of intertypic-reactive monoclonal antibodies. This revealed a universal epitope in VP2N which could be used as a peptide antigen to detect FMDV-specific antibodies against all types of the virus. A VP2-peptide ELISA (VP2-ELISA) was optimised using experimental and reference antisera from immunized, convalescent and negative animals (n=172). The VP2-ELISA is universal, simple and provided sensitive (98.6 %) and specific (93%) detection of antibodies to all FMDV strains used in this study. We anticipate that this SP test could have utility for sero-surveillance during virus incursions in FMD-free countries and as an additional screening tool to assess FMD virus circulation in endemic countries.

Infectious bursal disease virus (IBDV) vaccines do not induce sterilizing immunity, and vaccinated birds can become infected with field strains. Vaccine-induced immune selection pressure drives the evolution of antigenic drift variants that accumulate amino acid changes in the hypervariable region (HVR) of the VP2 capsid, which may lead to vaccine failures. However, there is a lack of information regarding how quickly mutations arise, and the relative contribution different residues make to immune escape. To model IBDV antigenic drift in vitro, we serially passaged a classical field strain belonging to genogroup A1 (F52/70) ten times, in triplicate, in the immortalized chicken B cell line, DT40, in the presence of sub-neutralizing concentrations of sera from birds inoculated with IBDV vaccine strain 2512, to generate escape mutants. This assay simulated a situation where classical strains may infect birds that have suboptimal vaccine-induced antibody responses. We then sequenced the HVR of the VP2 capsid at passage (P) 5 and 10 and compared the sequences to the parental virus (P0), and to the virus passaged in the presence of negative control chicken serum that lacked IBDV antibodies. Two escape mutants at P10 had the same mutations, D279Y and G281R, and a third had mutations S251I and D279N. Furthermore, at P5, the D279Y mutation was detectable, but the G281R mutation was not, indicating the mutations arose with different kinetics.

Foot-and-mouth disease (FMD) affects economically important livestock and is one of the most contagious viral diseases. The most commonly used FMD diagnostic assay is a sandwich ELISA. However, the main disadvantage of this ELISA is that it requires anti-FMD virus (FMDV) serotype-specific antibodies raised in small animals. This problem can be, in part, overcome by using anti-FMDV monoclonal antibodies (MAbs) as detecting reagents. However, the long-term use of MAbs may be problematic and they may need to be replaced. Here we have constructed chimeric antibodies (mouse/rabbit D9) and Fabs (fragment antigen-binding) (mouse/cattle D9) using the Fv (fragment variable) regions of a mouse MAb, D9 (MAb D9), which recognises type O FMDV. The mouse/rabbit D9 chimeric antibody retained the FMDV serotype-specificity of MAb D9 and performed well in a FMDV detection ELISA as well as in routine laboratory assays. Cryo-electron microscopy analysis confirmed engagement with antigenic site 1 and peptide competition studies identified the aspartic acid at residue VP1 147 as a novel component of the D9 epitope. This chimeric expression approach is a simple but effective way to preserve valuable FMDV antibodies, and has the potential for unlimited generation of antibodies and antibody fragments in recombinant systems with the concomitant positive impacts on the 3Rs (Replacement, Reduction and Refinement) principles.

The central theme of this study is the analysis of the procedural instruments of jurisdictional control of the regulations from a comparative perspective between the Brazilian and Portuguese legal systems, an admittedly attractive topic, and still of great practical use. The methodology used here consists of an analytical comparison between the two legal systems regarding legal actions with a view to exercising due control over regulatory acts, as a way of consolidating the democratic rule of law.

In order to better understand differences in the outcome of infectious bursal disease virus (IBDV) infection, we inoculated a very virulent (vv) strain into White Leghorn chickens of inbred line W that was previously reported to experience over 24% flock mortality, and three inbred lines (15I, C.B4 and 0) that were previously reported to display no mortality. Within each experimental group, some individuals experienced more severe disease than others but line 15I birds experienced milder disease based on average clinical scores, percentage of birds with gross pathology, average bursal lesion scores and average peak bursal virus titre. RNA-Seq analysis revealed that more severe disease in line W was associated with significant up-regulation of pathways involved in inflammation, cytoskeletal regulation by Rho GTPases, nicotinic acetylcholine receptor signaling, and Wnt signaling in the bursa compared to line 15I. Primary bursal cell populations isolated from uninfected line W birds contained a significantly greater percentage of KUL01+ macrophages than cells isolated from line 15I birds (p < 0.01) and, when stimulated ex vivo with LPS, showed more rapid up-regulation of pro-inflammatory gene expression than those from line 15I birds. We hypothesize that a more rapid induction of pro-inflammatory cytokine responses in bursal cells following IBDV infection leads to more severe disease in line W birds than in line 15I.

Background Bovine mastitis caused by Staphylococcus aureus is considered a public health threat globally. Herein, we aimed to investigate the occurrence, agr typing, antimicrobial resistance patterns, biofilm production, and PCR-based detection of the virulence, biofilm, adhesion, and enterotoxins genes of S. aureus strains recovered from clinical and subclinical bovine mastitis. Results The prevalence of S. aureus in the examined milk samples was 44.4%. Besides, 95% of the retrieved S. aureus strains were identified as MRSA. Herein, all the tested isolates were biofilm producers. PCR revealed that 85% of the retrieved S. aureus strains were positive for the agr I gene. Furthermore, the clf B, clf A, fnb B, fnb A, and cna genes were detected with a prevalence of 100%, 80%, 60%, 55%, and 30%, respectively. Also, all the tested S. aureus strains were positive for the coa gene (100%). Besides, 92.5% and 85% of the recovered strains harbored the luk F and spa genes, respectively. In addition, the prevalence of the hla , hlb , and hlg hemolysin genes was 70%, 50%, and 35%, respectively. Among the enterotoxin genes, the seb gene was detected in 30% of the tested strains. The prevalence of eno and ica A biofilm genes was 95% in the tested strains. Moreover, 15% of S. aureus strains were MDR to 8 antimicrobial agents and harbored the  mec A, erm C, and erm B genes. As well, 12.5% of S. aureus strains were MDR to 8 antimicrobial agents and carried the mec A, erm C, erm B, tet K, and tet M genes. Also, 5% of S. aureus strains were XDR to 11 antimicrobial agents and carried the  mec A, erm C, and erm B genes. Conclusions The existence of MDR and XDR MRSA strains in bovine milk is a public health hazard. The mec A, erm C, erm B, tet K, and tet M resistance genes and the coa, clf B, eno, ica A, lukF , spa , clf A, and hla virulence genes are commonly associated with the MDR and XDR MRSA strains. Moreover, the seb gene was the predominant enterotoxin gene in the MRSA strains recovered from milk.