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BMC Veterinary Research Oct 2023Thirty-two-day-old broiler chickens at a farm located in northwestern South Korea displayed adverse neurological symptoms including limping, lying down, and head...
BACKGROUND
Thirty-two-day-old broiler chickens at a farm located in northwestern South Korea displayed adverse neurological symptoms including limping, lying down, and head shaking. Approximately 2.1% of chickens died or were culled due to severe symptoms. Five carcasses were submitted to the Avian Disease Division of the Animal and Plant Quarantine Agency (APQA) for disease diagnosis.
RESULTS
Broilers displayed severe pericarditis and perihepatitis associated with gross lesions. Broilers also displayed microscopic lesions in the cerebrum and in the granular layer of the cerebellum, which were associated with multifocal perivascular cuffing and purulent necrosis in the cerebrum, and severe meningitis with heterophil and lymphocyte infiltration. Staphylococcus spp. were identified in the liver and heart using bacteriological culture. PCR/RT-PCR assays revealed that broilers were negative for avian Clostridium botulinum, Newcastle disease virus, and avian encephalomyelitis virus. Bacterial and viral metagenomic analysis of brain sample further revealed the presence of Pseudomonas spp. and Marek's disease virus, which are known etiological agents of chicken meningoencephalitis.
CONCLUSIONS
This study reports a diagnostic analysis of gross and histopathological lesions from 32-day-old broilers displaying unique neurological symptoms that revealed the presence of the several neurological diseases including meningoencephalitis. The causative agents associated with meningoencephalitis of broilers that had not been identified by routine diagnostic methods could be diagnosed by metagenomics, which proves the usefulness of metagenomics as a diagnostic tool for unknown neurological diseases in broilers.
Topics: Animals; Chickens; Newcastle disease virus; Newcastle Disease; Brain; Meningoencephalitis; Poultry Diseases
PubMed: 37798783
DOI: 10.1186/s12917-023-03732-y -
Poultry Science Apr 2020In poultry, viral infections (e.g., Marek's disease virus, avian leukosis virus, influenza A virus, and so on) can cause devastating mortality and economic losses.... (Review)
Review
In poultry, viral infections (e.g., Marek's disease virus, avian leukosis virus, influenza A virus, and so on) can cause devastating mortality and economic losses. Because viruses are solely dependent on host cells to propagate, they alter the host intracellular microenvironment. Thus, understanding the virus-host interaction is important for antiviral immunity and drug development in the poultry industry. MicroRNAs are crucial posttranscriptional regulators of gene expression in a wide spectrum of biological processes, including viral infection. Recently, microRNAs have been identified as key players in virus-host interactions. In this review, we will discuss the intricacies involved in the virus-host cross-talk mediated by host and viral microRNAs in poultry (i.e., chicken and ducks), as well as recent trends and challenges in this field. These findings may provide some insights into the rapidly developing area of research regarding viral pathogenesis and antiviral immunity in poultry production.
Topics: Animals; Chickens; Ducks; Host-Pathogen Interactions; Immunity, Innate; MicroRNAs; Poultry Diseases; RNA, Viral; Receptor Cross-Talk; Virus Diseases
PubMed: 32241464
DOI: 10.1016/j.psj.2019.11.053 -
Frontiers in Immunology 2022Innate immunity is not only the first line of host defense against pathogenic infection, but also the cornerstone of adaptive immune response. Upon pathogenic infection,... (Review)
Review
Innate immunity is not only the first line of host defense against pathogenic infection, but also the cornerstone of adaptive immune response. Upon pathogenic infection, pattern recognition receptors (PRRs) of host engage pathogen-associated molecular patterns (PAMPs) of pathogens, which initiates IFN production by activating interferon regulatory transcription factors (IRFs), nuclear factor-kappa B (NF-κB), and/or activating protein-1 (AP-1) signal transduction pathways in host cells. In order to replicate and survive, pathogens have evolved multiple strategies to evade host innate immune responses, including IFN-I signal transduction, autophagy, apoptosis, necrosis, inflammasome and/or metabolic pathways. Some avian viruses may not be highly pathogenic but they have evolved varied strategies to evade or suppress host immune response for survival, causing huge impacts on the poultry industry worldwide. In this review, we focus on the advances on innate immune evasion by several important avian immunosuppressive viruses (infectious bursal disease virus (IBDV), Marek's disease virus (MDV), avian leukosis virus (ALV), etc.), especially their evasion of PRRs-mediated signal transduction pathways (IFN-I signal transduction pathway) and IFNAR-JAK-STAT signal pathways. A comprehensive understanding of the mechanism by which avian viruses evade or suppress host immune responses will be of help to the development of novel vaccines and therapeutic reagents for the prevention and control of infectious diseases in chickens.
Topics: Animals; Chickens; Immune Evasion; Immunity, Innate; Immunosuppressive Agents; Interferon Regulatory Factors; Pathogen-Associated Molecular Pattern Molecules; Receptors, Pattern Recognition; Viruses
PubMed: 35634318
DOI: 10.3389/fimmu.2022.901913 -
Molecular Therapy Oncolytics Sep 2023Unraveling the complexities of the tumor microenvironment (TME) and its correlation with responsiveness to immunotherapy has become a main focus in overcoming resistance...
Unraveling the complexities of the tumor microenvironment (TME) and its correlation with responsiveness to immunotherapy has become a main focus in overcoming resistance to such treatments. Targeting tumor-intrinsic retinoic acid-inducible gene-I (RIG-I), a sensor for viral RNA, was shown to transform the TME from an immunogenically "cold" state to an inflamed, "hot" lesion, which we demonstrated previously to be a crucial mediator of the efficacy of immune checkpoint inhibition with anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4). In this study, we focus on the chimeric oncolytic virus vesicular stomatitis virus (VSV)-Newcastle disease virus (NDV), comprised of genetic components of VSV and NDV, and we investigate its utility to support tumor-intrinsic RIG-I-dependent therapy with anti-CTLA-4. Overall, we demonstrate that treatment with VSV-NDV efficiently delays tumor growth and significantly prolongs survival in a murine model of malignant melanoma, which was further enhanced in combination with anti-CTLA-4. Although the direct oncolytic and pro-inflammatory effects of VSV-NDV therapy were independent of RIG-I activation, the synergism with anti-CTLA-4 therapy and associated activation of tumor-specific T cells was critically dependent on active RIG-I signaling in tumor cells. This work highlights the therapeutic value of utilizing an immune-stimulatory oncolytic virus to sensitize tumors to immune checkpoint inhibition.
PubMed: 37654972
DOI: 10.1016/j.omto.2023.08.001 -
Microorganisms Mar 2023Marek's disease virus (MDV), an Alphaherpesvirus belonging to the genus Mardivirus, causes T cell lymphomas in chickens and remains one of the greatest threats to...
Marek's disease virus (MDV), an Alphaherpesvirus belonging to the genus Mardivirus, causes T cell lymphomas in chickens and remains one of the greatest threats to poultry production worldwide [...].
PubMed: 36985378
DOI: 10.3390/microorganisms11030805 -
Vaccines Nov 2018Avian viral diseases including avian influenza, Marek's disease and Newcastle disease are detrimental to economies around the world that depend on the poultry trade. A... (Review)
Review
Avian viral diseases including avian influenza, Marek's disease and Newcastle disease are detrimental to economies around the world that depend on the poultry trade. A significant zoonotic threat is also posed by avian influenza viruses. Vaccination is an important and widely used method for controlling these poultry diseases. However, the current vaccines do not provide full protection or sterile immunity. Hence, there is a need to develop improved vaccines. The major aim of developing improved vaccines is to induce strong and specific humoral and cellular immunity in vaccinated animals. One strategy used to enhance the immunogenicity of vaccines is the selective delivery of protective antigens to antigen-presenting cells (APCs) including dendritic cells, macrophages and B cells. APCs have a central role in the initiation and maintenance of immune responses through their ability to capture, process and present antigens to T and B cells. Vaccine technology that selectively targets APCs has been achieved by coupling antigens to monoclonal antibodies or ligands that are targeted by APCs. The aim of this review is to discuss existing strategies of selective delivery of antigens to APCs for effective vaccine development in poultry.
PubMed: 30445683
DOI: 10.3390/vaccines6040075 -
Journal of Virology May 2022Circular RNAs (circRNAs) are a recently rediscovered class of functional noncoding RNAs that are involved in gene regulation and cancer development. Next-generation...
Circular RNAs (circRNAs) are a recently rediscovered class of functional noncoding RNAs that are involved in gene regulation and cancer development. Next-generation sequencing approaches identified circRNA fragments and sequences underlying circularization events in virus-induced cancers. In the present study, we performed viral circRNA expression analysis and full-length sequencing in infections with Marek's disease virus (MDV), which serves as a model for herpesvirus-induced tumorigenesis. We established inverse PCRs to identify and characterize circRNA expression from the repeat regions of the MDV genome during viral replication, latency, and reactivation. We identified a large variety of viral circRNAs through precise mapping of full-length circular transcripts and detected matching sequences with several viral genes. Hot spots of circRNA expression included the transcriptional unit of the major viral oncogene encoding the Meq protein and the latency-associated transcripts (LATs). Moreover, we performed genome-wide bioinformatic analyses to extract back-splice junctions from lymphoma-derived samples. Using this strategy, we found that circRNAs were abundantly expressed from the same key virulence genes. Strikingly, the observed back-splice junctions do not follow a unique canonical pattern, compatible with the U2-dependent splicing machinery. Numerous noncanonical junctions were observed in viral circRNA sequences characterized from and infections. Given the importance of the genes involved in the transcription of these circRNAs, our study contributes to our understanding and complexity of this deadly pathogen. Circular RNAs (circRNAs) were rediscovered in recent years both in physiological and pathological contexts, such as in cancer. Viral circRNAs are encoded by at least two human herpesviruses, the Epstein Barr virus and the Kaposi's Sarcoma-associated herpesvirus, both associated with the development of lymphoma. Marek's disease virus (MDV) is a well-established animal model to study virus-induced lymphoma but circRNA expression has not been reported for MDV yet. Our study provided the first evidence of viral circRNAs that were expressed at key steps of the MDV lifecycle using genome-wide analyses of circRNAs. These circRNAs were primarily found in transcriptional units that corresponded to the major MDV virulence factors. In addition, we established a bioinformatics pipeline that offers a new tool to identify circular RNAs in other herpesviruses. This study on the circRNAs provided important insights into major MDV virulence genes and herpesviruses-mediated gene dysregulation.
Topics: Animals; Chickens; Epstein-Barr Virus Infections; Genome-Wide Association Study; Herpesvirus 2, Gallid; Lymphoma; Marek Disease; Oncogene Proteins, Viral; RNA, Circular; RNA, Untranslated; Virulence
PubMed: 35412345
DOI: 10.1128/jvi.00321-22 -
Virusdisease Sep 2018Marek's disease (MD) and lymphoid leucosis (LL) are the major diseases causing lymphoid tumors in chickens accounting for high economical losses. Gross examination could...
Marek's disease (MD) and lymphoid leucosis (LL) are the major diseases causing lymphoid tumors in chickens accounting for high economical losses. Gross examination could not yield definite diagnosis owing to their similar presentation of lesions. Thus present work was aimed for diagnosis and differentiation of MD and LL by utilizing simple cytology and novel immunocytology techniques. Cytological examination was carried out on slides with tumor touch imprints stained by simple Giemsa staining. The diagnosis was mainly achieved based on morphology of cell population. In the present study, out of a total of 595 cases examined, 502 cases had pleomorphic lymphocytic cell population suggestive of MD and 53 cases had uniform lymphocytic/lymphoblast cell population suggestive of LL, while the rest 40 cases remained inconclusive. A definitive diagnosis was achieved after performing immunocytology using specific antibodies that revealed 518 cases had reactivity for Meq oncoprotein specific for MD and 77 cases showed immunoreactivity for IgM in transformed B-cells confirming LL. The technique of immunocytology which has been useful for detecting human viral pathogens and MD in poultry has been applied for the first time as a novel, simple, rapid and inexpensive technique that could be used as an alternate test to effectively detect and differentiate MD and LL in poultry.
PubMed: 30159370
DOI: 10.1007/s13337-018-0471-3 -
Viruses Nov 2021Herpes simplex virus type 1, or HSV-1, is a widespread human pathogen that replicates in epithelial cells of the body surface and then establishes latent infection in... (Review)
Review
Herpes simplex virus type 1, or HSV-1, is a widespread human pathogen that replicates in epithelial cells of the body surface and then establishes latent infection in peripheral neurons. When HSV-1 replicates, viral progeny must be efficiently released to spread infection to new target cells. Viral spread occurs via two major routes. In cell-cell spread, progeny virions are delivered directly to cellular junctions, where they infect adjacent cells. In cell-free release, progeny virions are released into the extracellular milieu, potentially allowing the infection of distant cells. Cell-cell spread of HSV-1 has been well studied and is known to be important for in vivo infection and pathogenesis. In contrast, HSV-1 cell-free release has received less attention, and its significance to viral biology is unclear. Here, I review the mechanisms and regulation of HSV-1 cell-free virion release. Based on knowledge accrued in other herpesviral systems, I argue that HSV-1 cell-free release is likely to be tightly regulated in vivo. Specifically, I hypothesize that this process is generally suppressed as the virus replicates within the body, but activated to high levels at sites of viral reactivation, such as the oral mucosa and skin, in order to promote efficient transmission of HSV-1 to new human hosts.
Topics: Animals; Cell Line; Cell-Free System; Herpes Simplex; Herpesvirus 1, Human; Humans; Virion; Virus Release
PubMed: 34960664
DOI: 10.3390/v13122395 -
International Journal of Occupational... 2016Isoprostanes are a recently discovered group of prostaglandin isomers. Results of previous studies suggest that they can be used as oxidative stress markers, because in... (Review)
Review
Isoprostanes are a recently discovered group of prostaglandin isomers. Results of previous studies suggest that they can be used as oxidative stress markers, because in a number of cardiovascular, pulmonary and neurological diseases their levels in biological samples considerably increase. It has been found that people suffering from diabetes, obesity, homozygous familial hypercholesterolemia, moderate hypercholesterolemia, and smokers have higher levels of isoprostanes in urine. The same refers to patients with asthma, Alzheimer disease and Down syndrome. This paper reviews the results of relevant studies.
Topics: Biomarkers; Cardiovascular Diseases; Humans; Isoprostanes; Oxidative Stress
PubMed: 26670350
DOI: 10.13075/ijomeh.1896.00596