Refinar búsqueda
Resultados 1-10 de 11
Mink SARS-CoV-2 infection in Poland – short communication
2021
Domańska-Blicharz, Katarzyna | Orłowska, Anna | Smreczak, Marcin | Niemczuk, Krzysztof | Iwan, Ewelina | Bomba, Arkadiusz | Lisowska, Anna | Opolska, Justyna | Trębas, Paweł | Potyrało, Patrycja | Kawiak-Sadurska, Magdalena | Rola, Jerzy
Since April 2020, when the first SARS-CoV-2 infection was reported in mink and subsequently in mink farm workers in the Netherlands, it has been confirmed that human-to-mink and mink-to-human transmission can occur. Later, SARS-CoV-2 infections in mink were reported in many European and North American countries. Samples from 590 mink from a total of 28 farms were tested by real-time RT-PCR. Whole genome sequences from one positive farm were generated and genetic relatedness was established. SARS-CoV-2 RNA was detected on a breeder farm with stock of 5,850 mink. Active viraemia was confirmed in individually tested samples with Ct values respectively between 19.4 and 29.6 for E and N gene fragments. Further testing of samples from culled animals revealed 70% positivity in throat swabs and 30% seropositivity in blood samples. Phylogenetic analysis of full-length nucleotide sequences of two SARS-CoV-2 isolates revealed that they belong to the 20B Nextstrain clade. Several nucleotide mutations were found in analysed samples compared to the reference Wuhan HU-1 strain and some of them were nonsynonymous. We report the infection of mink with SARS-CoV-2 on one farm in Poland and the results of subsequent analysis of virus sequences from two isolates. These data can be useful for assessment of the epidemiological situation of SARS-CoV-2 in Poland and how it endangers public health.
Mostrar más [+] Menos [-]Tk-deleted pseudorabies virus retains high pathogenicity in rats
2021
Zhang, Lirong | Ruan, Keyue | Sang, Guoju | Xu, Zhaoyang | Tong, Wu | Yu, Hai | Shan, Tongling | Gao, Fei | Li, Liwei | Kong, Ning | Tong, Guangzhi | Zheng, Hao
The pseudorabies virus (PRV) gene encoding thymidine kinase (tk) is an important virulence-associated factor. Attenuation of PRV in susceptible animals is a frequent result of tk deletion. The aim of the study was to assess the pathogenicity of tk-deleted PRV in rats. Sprague Dawley rats were infected with the tk-deleted PRV strain SuHV-1 ΔTK:247via intranasal or intramuscular inoculation. PRV loads in ten tissues from dead and euthanised rats were determined using real-time PCR. Infection with SuHV-1 ΔTK:247 could cause death in rats. The 50% lethal dose (LD₅₀) of SuHV-1 ΔTK:247 via intranasal inoculation was 10³.¹⁶ TCID₅₀ in rats. Intramuscular inoculation required a higher dose of SuHV-1 ΔTK:247 (10⁵.⁰ TCID₅₀). A high SuHV-1 ΔTK:247 titre was observed in the trigeminal ganglia or spinal cord of dead rats. The results of this study show that rats are highly susceptible to PRV infection, and tk deletion did not completely diminish the pathogenicity of PRV in rats.
Mostrar más [+] Menos [-]Prevalence of Toxoplasma gondii in retail fresh meat products from free-range chickens in Spain
2021
Salinas, María Jesús Gracia | Campos, Cristina Escolano | Peris, María Paz Peris | Kassab, Nabil Halaihel
Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites worldwide and affects the vast majority of warm-blooded animal species, including humans. Postnatal infection in humans occurs through the ingestion of sporulated T. gondii oocysts or via the oral intake of parasite tissue cysts during the consumption of raw or undercooked meat. In this regard, given their high exposure to oocysts, chickens (Gallus domesticus) raised on the ground constitute a potential source of T. gondii. For the first time in Spain, a survey was undertaken in commercial retail free-range poultry. A total of 50 thighs from different animals were analysed. The samples were homogenised and an acid pepsin digestion procedure was applied prior to molecular analysis. Toxoplasma gondii DNA was isolated from meat by qPCR. Two sets of primers were used for DNA amplification targeting the specific sequence of a 529 bp repeat element and another set of primers was utilised for the surface antigen protein-1 gene. DNA extracted from 5 out of 50 tissue samples was positive for both genes by qPCR amplification. The 10% prevalence of Toxoplasma infection found in commercial free-range chickens raises public health issues.
Mostrar más [+] Menos [-]Comparative expression analysis of inflammatory and immune-related genes in cattle during acute infection with foot-and-mouth disease virus in Egypt
2021
El Nahas, Abeer F. | Abd El Naby, Walaa S.H. | Khatab, Shymaa A. | Fergany, Al-Zahraa A. | Rashed, Rashed R.
Foot-and-mouth disease is a highly infectious viral disease affecting all cloven-footed domestic animals. The three foot-and-mouth disease virus (FMDV) serotypes A, O and SAT2 are at present the greatest threat to susceptible animals in Egypt. The aim of the present study was, for the host factors associated with different FMDV infections in cattle during the acute phase, to compare these factors’ influence on the expression of the IL-10, TLR-2, TNF-α, CXCL10, CD48, NFATC4 and IFNG inflammatory and immune-related genes. Vesicular fluid and epithelium samples were obtained from at least three infected cattle on the same affected farm during three different FMDV outbreaks and were used for serotyping of the virus and for expression analysis of host genes. A two-step RT-PCR was used for diagnosis of the virus with primers specific for each serotype. In quantitative PCR analysis, the expression patterns of TLR-2 and IFNG were prominent, while NFATC4 expression was absent in all FMDV-infected cattle. The highest expression of CD48 was associated with increased expression of other inflammatory and immune-related genes (IL-10, TLR-2, TNF-α and IFNG), which may be an indication of rapid virus clearance. The use of vesicular fluid and epithelium for investigation of viral and immune-related gene expression levels in acute FMDV infection is possible. Host-dependent variation in the expression of the studied genes was observed in different FMDV serotype outbreaks.
Mostrar más [+] Menos [-]Comparison of chicken immune responses after inoculation with H5 avian influenza virus-like particles produced by insect cells or pupae
2021
Huang, Dean | Chao, Yu-Chan | Lv, Zhengbing | Jan, Jia-Tsrong | Yang, Yuzhi | Hsiao, Pei-Wen | Wu, Jiaying | Liao, Chiu-Hsun | Wu, Tzu-Hsien | Wang, Lih-Chiann
Novel clade 2.3.4.4 H5 highly pathogenic avian influenza virus (HPAIV) outbreaks have occurred since early 2015 in Taiwan and impacted the island economically, like they have many countries. This research investigates the immunogenicity of two HPAIV-like particles to assess their promise as vaccine candidates. The haemagglutinin (HA) gene derived from clade 2.3.4.4 H5 HPAIV and matrix protein 1 (M1) gene were cloned into the pFastBac Dual baculovirus vector. The resulting recombinant viruses were expressed in Spodoptera frugiperda moth (Sf)21 cells and silkworm pupae to generate Sf21 virus-like particles (VLP) and silkworm pupa VLP. Two-week-old specific pathogen–free chickens were immunised and their humoral and cellular immune responses were analysed. The silkworm pupa VLP had higher haemagglutination competence. Both VLP types elicited haemagglutination inhibition antibodies, anti-HA antibodies, splenic interferon gamma (IFN-γ) and interleukin 4 (IL-4) mRNA expression, and CD4⁺/CD8⁺ ratio elevation. However, chickens receiving silkworm pupa VLP exhibited a significantly higher anti-HA antibody titre in ELISA after vaccination. Although Sf21 VLP recipients expressed more IFN-γ and IL-4, the increase in IFN-γ did not significantly raise the CD4⁺/CD8⁺ ratio and the increase in IL-4 did not promote anti-HA antibodies. Both VLP systems possess desirable immunogenicity in vivo. However, in respect of immunogenic efficacy and the production cost, pupa VLP may be the superior vaccine candidate against clade 2.3.4.4 H5 HPAIV infection.
Mostrar más [+] Menos [-]New insights into the prevalence and phylogenetic diversity of Cysticercus ovis isolates in sheep from Sulaymaniyah, Iraq
2021
Although ovine cysticercosis is not a zoonotic problem, it results in substantial economic losses due to the condemnation of infected tissues or entire carcasses. This study aimed to record preliminary data on the prevalence, and phylogenetic diversity of Cysticercus ovis isolates from slaughtered sheep in the province of Sulaymaniyah, Iraq. From January to September 2020, 6, 411 slaughtered sheep were examined for C. ovis by routine meat inspection. The amplification and sequence analysis of the COX1 gene for up to 35 specimens of C. ovis was performed using conventional PCR. The overall prevalence rate was 1.3%, and the prevalence was significantly higher in older sheep (>1 year) than younger ones (<1 year) (P< 0.05). The cardiac muscle showed a higher tendency to carry C. ovis infection compared to other examined muscles. Sequence analysis of the COX1 gene revealed six haplotypes, and the level of pairwise nucleotide diversity between individual haplotypes was 1–2%. Five out of six of the Taenia ovis haplotypes recovered could have been recorded for the first time globally. Phylogenetic interpretation indicated that all the T. ovis haplotypes clustered in a single clade, and it also indicated an extremely close similarity to Iranian and New Zealand isolates. Globally, this report adds new data on C. ovis genetic diversity, which provide an extremely useful molecular background with regard to future preventive as well as control strategies.
Mostrar más [+] Menos [-]Expression, purification, and bioactivity of a soluble recombinant ovine interferon-tau in Escherichia coli
2021
Yu, Hai-Yang | Gao, Dong-Mei | Zhou, Wei | Xia, Bing-Bing | He, Zhi-Yuan | Wu, Bo | Jiang, Min-Zhi | Wang, Mingli | Zhao, Jun
Ovine interferon-tau (oIFN-τ) is a newly discovered type I interferon. This study used biochemical techniques to transform the oIFN-τ gene into Escherichia coli to obtain the mass and soluble expression of the recombinant protein. First, total RNA was extracted from fresh sheep embryonic tissues with TRIzol reagent and then used as a template to reverse transcribe and amplify the mature oIFN-τ gene with RT-PCR. The amplified product was next digested with the HindIII and XhoI restriction enzymes and inserted into the pET-32a(+) vector to construct the prokaryotic expression plasmid. The corrected in-frame recombinant plasmid, pET-32a(+)-oIFN-τ, was transformed into E. coli Rosetta (DE3) competent cells. After induction with isopropyl-beta-D-thiogalactopyranoside (IPTG), the recombinant protein was detected in bacteria. Finally, the bacteria were lysed by sonication, and the recombinant protein was purified by nickel affinity chromatography and DEAE anion exchange chromatography. The protein was confirmed to be oIFN-τ, which mainly existed in the soluble lysate fraction, as proven by SDS-PAGE and Western blot assays. Purified IFN-τ exists mostly in a soluble form, and its anti-vesicular stomatitis virus (VSV) activity reached 7.08×10(6)IU/mL.
Mostrar más [+] Menos [-]Nasal bacterial microbiota during an outbreak of equine herpesvirus 1 at a farm in southern Ontario
2021
Gomez, Diego E. | Arroyo, Luis G. | Lillie, Brandon | Weese, J Scott
The objective of this study was to investigate the nasal bacterial microbiota of healthy horses and horses infected with equine herpesvirus 1 (EHV-1). The nasal bacterial microbiota of 10 horses infected with EHV-1 and 11 control horses from a farm experiencing an outbreak was characterized using the Illumina MiSeq platform targeting the V4 region of the 16S ribosomal RNA gene. The nasal bacterial microbiota of healthy horses and EHV-1 horses was significantly different in community membership and structure. Horses shedding EHV-1 had lower bacterial richness (P = 0.002), evenness (P = 0.008), and diversity (P = 0.026) than healthy horses. Healthy horses had a higher relative abundance of Firmicutes and Bacteroidetes, but lower Proteobacteria than horses with EHV-1 (P < 0.05). This study provides the basis for generating hypotheses and investigations on the role of bacterial-viral interactions in the health and diseases of adult horses.
Mostrar más [+] Menos [-]Description of the bacterial microbiota of anal sacs in healthy dogs
2021
Bergeron, Camylle C. | Costa, Marcio C. | Souza, Lucilene B de | Sauve, Frederic
The aim of the present study was to characterize the bacterial microbiota of anal sacs in healthy dogs using NGS. Swabs were used to sample the rectum and secretions from each anal sac in 15 healthy dogs. DNA was extracted from swabs and the V4 hypervariable region of the 16S rRNA gene was amplified and sequenced with Illumina MiSeq. Overall, 14 different bacterial phyla were identified in the rectum and in both anal sacs, the 5 main ones being Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Fusobacteria. The rectum had higher microbial diversity and richness than the left and right anal sacs. Community membership and structure significantly differed between the rectum and both anal sacs, but not between the right and the left anal sacs. This study showed that the diversity and richness of the bacterial microbiota of the anal sacs in dogs is greater than what has been reported in previous studies with culture-based methods. In conclusion, the bacterial microbiota of the anal sacs in dogs varies between individuals and differs from the rectal bacterial microbiota.
Mostrar más [+] Menos [-]Development of a biologically immortalized equine stem cell line
2021
Nino-Fong, Rodolfo | Esparza Gonzlaez, Blanca P. | Rodriguez-Lecompte, Juan Carlos | Montelpare, William | McDuffee, Laurie
Bone repair in horses implies invasive surgeries and increased cost. Research on musculoskeletal disorders therapy in horses includes cell-based therapy with mesenchymal stromal cells (MSCs). Mesenchymal stromal cells can be obtained from bone marrow (BMMSCs). Unfortunately, BMMSCs have limited cell replication in vitro. The objective of this study was to develop a biologically immortalized equine stem cell line derived from bone marrow, with unlimited in-vitro proliferation and the ability to differentiate into bone cells. Equine BMMSCs were transfected and immortalized with human telomerase reverse transcriptase (hTERT) gene. Cell passages from equine immortal BMMSCs were characterized by the presence of stemness CD markers and expression of multi-potent differentiation genes (OCT-4, SOX2, and NANOG). Equine immortal BMMSCs were incubated in osteogenic medium and bone cell differentiation was determined by alkaline phosphatase and von Kossa staining, and osteogenic gene expression (osteocalcin, Runx2, and osterix). Telomerase activity was determined by telomeric repeat amplification technique. Results showed that equine immortal BMMSCs were able to replicate in-vitro up to passage 50 and maintain stem cell characteristics by the presence of CD90 and expression of multi-potent genes. Equine immortal BMMSCs were able to differentiate into bone cells, which was confirmed by the positive osteogenic staining and gene expression. Equine BMMSCs were successfully immortalized and maintained characteristics of stem cells and readily differentiated into osteogenic cells. Extending the life span of equine BMMSCs by transfection of the hTERT gene will revolutionize the clinical use of MSCs by making them available to orthopedic surgeons "off the shelf."
Mostrar más [+] Menos [-]