Conserve Epitopes of Influenza Virus Induce Innate and Adaptive Immune Responses to Produce Specific Antibody Against M2e Protein

The existing vaccines against influenza are based onthe generation of neutralizing antibody primarilydirected against surface protein, haemagglutinin(HA) and neuraminidase (NA). However, antigenicdrift and occasional shift of these two membraneglycoproteins, HA and NA, make vaccine productioncumbersome and necessitate yearly revision ofthe vaccine seed strains by the World HealthOrganization. For these reasons, many investigatorshave often tried to look at the possibility of generatinga universal vaccine useful against more than oneinfluenza strain. The objective of research was toobtain an alternative antigen as vaccine candidatefor universal flu vaccination, instead of HA and NAcomponents. In this study, we use conserved epitopeM2e which is consist of three major componentsuch as N-terminal M2e2-24 (24 amino acids),transmembrane(59 amino acids) and C-terminal (19amino acids). We design two components of antigen,linier and branched structures. The antigens thenformulated with aluminium hydroxide gel comparedto FCA/IFA adjuvant. These vaccines were testedtheir immunogenicity, and the potency to mature thedendritic cells for stimulating either CD8+ T cell orantibody-mediated immune responses. The antibodytitre and the maturity of dendritic cell indicated bycytokines concentration such as; IFN-ã, IL2 and IL4were measured by ELISA test.The result of researchshowed that the conserved epitope of Me2 2-16 whenincorporated with P25 protein from canine distempervirus (linear structure) in alhydrogel adjuvant hasgreater potential to produce anti-M2e antibodiesthan in Freund adjuvant. Alhydrogel adjuvant hada stronger effect than Freund adjuvant. Alhydrogelalso stimulate the release of IL-2 and IL-4

Diverse strains of Actinobacillus lignieresii isolated from clinically affected cattle in a geographically restricted area

Objective: To investigate whether an outbreak of Actinobacillus lignieresii was caused by one or multiple strains. Methods: Nine isolates of A. lignieresii were obtained from the lymph nodes of 15 affected cattle from two farms to determine whether a single strain was involved. An enterobacterial repetitive insertion consensus sequence (ERIC) PCR was used for genotyping, and the repeats-in-toxin genes were analysed by PCR and sequencing. Results: Isolates from the two farms belonged to two and three genotypes, with a total of four genotypes detected. Genes of the apxICABD operons of some strains had deletions in the apxIA (~697 bp) and in the apxID (~187 bp) genes. The toxin gene deletions and the ERIC PCR patterns suggested the involvement of different A. lignieresii genotypes. Conclusion: There was no evidence that a unique genotype was associated with actinobacillosis on the two farms, confirming that this disease was associated with other contributing factors

Pathogens associated with pleuritic pig lungs at an abattoir in Queensland Australia

Objective Pleurisy in pigs has economic impacts in the production stage and at slaughter. This study sought to establish if some micro-organisms can be found in high numbers in lungs with pleurisy by assessing batches of pigs at an abattoir in Queensland Australia. Design Samples of lung (including trachea/bronchus and lymph nodes) from a maximum of 5 pleurisy affected pigs were collected from 46 batches of pigs representing 46 Queensland farms. Procedure Pleurisy-affected lung areas were cultured by traditional bacteriological methods and bacteria quantified by plate scores. Additionally, tracheal or bronchial swabs and apical lobe fluid were tested for Mycoplasma hyopneumoniae DNA and the superior tracheobronchial lymph nodes were tested for porcine circovirus type 2 DNA by polymerase chain reaction (PCR). All apparently significant bacteria were identified via PCR or sequencing. Typing was undertaken on some of the bacterial isolates. Results The most prevalent pathogens were M. hyopneumoniae, Streptococcus suis and Porcine Circovirus type 2, being found in 34, 38 and 31 batches, respectively. Other bacteria found were Actinobacillus species (29 batches), Pasteurella multocida (24 batches), Mycoplasma flocculare (9 batches), Actinobacillus pleuropneumoniae (7 batches), Mycoplasma hyorhinis (4 batches), Bisgaard Taxon 10 (1 batch), Glaesserella parasuis (1 batch), Streptococcus minor (1 batch) and Streptococcus porcinus (1 batch). Most batches had more than one bacterial species. Conclusion The high percentage of batches infected with S. suis (83%), M. hyopneumoniae (74%) and PCV2 (70%) and clustering by a batch of these pathogens, as well as the presence of many secondary pathogens, suggests synergy between these organisms may have resulted in pleurisy

Antimicrobial susceptibility and genomic analysis of Histophilus somni isolated from cases of bovine respiratory disease in Autralian feedlot cattle

Histophilus somni is a prevalent commensal organism of the upper respiratory tract of cattle and a major causative agent of bovine respiratory disease (BRD) and other syndromes including myocarditis and infectious thromboembolic meningoencephalitis. This study investigated the antimicrobial susceptibility and phylogenetic relationships of H. somni isolates obtained from lung, heart, and other tissues at post-mortem as well as nasal mucosa swabs from cases of BRD in Australian feedlots (2004–2019). Broth microdilution Minimal Inhibitory Concentration (MIC) assays were determined for 19 antimicrobials using three different media (CLSI approved Veterinary Fastidious Medium [VFM], Mueller-Hinton fastidious broth medium supplemented with yeast extract [MHF-Y] and Columbia Broth [CB] supplemented with 5% lysed horse blood). For all antimicrobials, MICs obtained using CB medium were identical or within 1 dilution step of the MICs obtained for VFM and MHF-Y media. Therefore, CB may be a suitable medium for H. somni antimicrobial susceptibility testing similar to MHF-Y medium. None of the 70 Australian H. somni isolates exhibited resistance to antimicrobials with CLSI breakpoints including those commonly used in the treatment of BRD in Australia (first-line tetracyclines [chlortetracycline and oxytetracycline], second-line macrolides [tulathromycin], and third-line extended-spectrum cephalosporin [ceftiofur]). Whole-genome sequence analysis of 65 H. somni isolates for genomic single nucleotide polymorphism differences identified four phylogenetic clusters, each containing isolates from different Australian states, feedlots and tissue sources that clustered together. These findings demonstrate limited genetic diversity and the absence of significant antimicrobial resistance among Australian isolates of H. somni isolated from feedlot cattle

Genomic analysis of phylogenetic group B2 extraintestinal pathogenic E. coli causing infections in dogs in Australia

This study investigated the prevalence of extraintestinal pathogenic E. coli (ExPEC)-associated sequence types (STs) from phylogenetic group B2 among 449 fluoroquinolone-susceptible dog clinical isolates from Australia. Isolates underwent PCR-based phylotyping and random amplified polymorphic DNA analysis to determine clonal relatedness. Of the 317 so-identified group B2 isolates, 77 underwent whole genome sequencing (WGS), whereas the remainder underwent PCR-based screening for ST complexes (STc) STc12, STc73, STc372, and ST131. The predominant ST was ST372 according to both WGS (31 % of 77) and ST-specific PCR (22 % of 240), followed by (per WGS) ST73 (17 %), ST12 (7 %), and ST80 (7 %). A WGS-based phylogenetic comparison of ST73 isolates from dogs, cats, and humans showed considerable overall phylogenetic diversity. Although most clusters were species-specific, some contained closely related human and animal (dog > cat) isolates. For dogs in Australia these findings both confirm ST372 as the predominant E. coli clonal lineage causing extraintestinal infections and clarify the importance of human-associated group B2 lineage ST73 as a cause of UTI, with some strains possibly being capable of bi-directional (i.e., dog-human and human-dog) transmission