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Scientific Reports Feb 2024Lymphoid leukosis is a poultry neoplastic disease caused by avian leukosis virus (ALV) and is characterized by high morbidity and variable mortality rates in chicks....
Lymphoid leukosis is a poultry neoplastic disease caused by avian leukosis virus (ALV) and is characterized by high morbidity and variable mortality rates in chicks. Currently, no effective treatment and vaccination is the only means to control it. This study exploited the immunoinformatics approaches to construct multi-epitope vaccine against ALV. ABCpred and IEDB servers were used to predict B and T lymphocytes epitopes from the viral proteins, respectively. Antigenicity, allergenicity and toxicity of the epitopes were assessed and used to construct the vaccine with suitable adjuvant and linkers. Secondary and tertiary structures of the vaccine were predicted, refined and validated. Structural errors, solubility, stability, immune simulation, dynamic simulation, docking and in silico cloning were also evaluated.The constructed vaccine was hydrophilic, antigenic and non-allergenic. Ramchandran plot showed most of the residues in the favored and additional allowed regions. ProsA server showed no errors in the vaccine structure. Immune simulation showed significant immunoglobulins and cytokines levels. Stability was enhanced by disulfide engineering and molecular dynamic simulation. Docking of the vaccine with chicken's TLR7 revealed competent binding energies.The vaccine was cloned in pET-30a(+) vector and efficiently expressed in Escherichia coli. This study provided a potent peptide vaccine that could assist in tailoring a rapid and cost-effective vaccine that helps to combat ALV. However, experimental validation is required to assess the vaccine efficiency.
Topics: Animals; Molecular Docking Simulation; Avian Leukosis Virus; Protein Subunit Vaccines; Immunoinformatics; Chickens; Epitopes, T-Lymphocyte; Molecular Dynamics Simulation; Epitopes, B-Lymphocyte; Vaccines, Subunit; Computational Biology
PubMed: 38311642
DOI: 10.1038/s41598-024-53048-6 -
BMC Veterinary Research Feb 2024The coinfection of ALVs (ALV-J plus ALV-A or/and ALV-B) has played an important role in the incidence of tumors recently found in China in local breeds of yellow...
The coinfection of ALVs (ALV-J plus ALV-A or/and ALV-B) has played an important role in the incidence of tumors recently found in China in local breeds of yellow chickens. The study aims to obtain a better knowledge of the function and relevance of ALV coinfection in the clinical disease of avian leukosis, as well as its unique effect on the pathogenicity in Three-yellow chickens. One-day-old Three-yellow chicks (one day old) were infected with ALV-A, ALV-B, and ALV-J mono-infections, as well as ALV-A + J, ALV-B + J, and ALV-A + B + J coinfections, via intraperitoneal injection, and the chicks were then grown in isolators until they were 15 weeks old. The parameters, including the suppression of body weight gain, immune organ weight, viremia, histopathological changes and tumor incidence, were observed and compared with those of the uninfected control birds. The results demonstrated that coinfection with ALVs could induce more serious suppression of body weight gain (P < 0.05), damage to immune organs (P < 0.05) and higher tumor incidences than monoinfection, with triple infection producing the highest pathogenicity. The emergence of visible tumors and viremia occurred faster in the coinfected birds than in the monoinfected birds. These findings demonstrated that ALV coinfection resulted in considerably severe pathogenic and immunosuppressive consequences.
Topics: Animals; Chickens; Coinfection; Virulence; Viremia; Avian Leukosis; Neoplasms; Body Weight; Avian Leukosis Virus; Poultry Diseases
PubMed: 38302973
DOI: 10.1186/s12917-024-03896-1 -
Viruses Dec 2023Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for the rapid detection of pathogens. A sensitive and specific multiple nanoPCR assay was...
Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for the rapid detection of pathogens. A sensitive and specific multiple nanoPCR assay was developed for simultaneous detection of avian leucosis virus (ALV) subgroups A, B and J. In this study, three pairs of primers were designed, based on the conserved region of the gp85 gene. An exploration of the optimal primer concentration and annealing temperature were carried out, for better performance of the nanoPCR assay. According to the results, the multiple nanoPCR assay amplified 336 pb, 625 bp and 167 bp fragments of ALV-A, -B and -J, respectively, and showed no cross-reactivity with irrelevant pathogens, suggesting the excellent specificity of the assay. The constructed standard DNA templates were used to estimate the limit of detection. As shown by the results, the detection limit of the nanoPCR assay was nearly 10 copies/μL. To further evaluate the detection ability of the assay, 186 clinical samples were detected using the nanoPCR assay, among which, 14 samples were confirmed as ALV positive; the results were further confirmed by sequencing. In conclusion, a highly specific and sensitive nanoPCR assay was successfully developed, which could be a useful tool for clinical diagnosis as well as for the discrimination of ALV-A, -B and -J.
Topics: Animals; Avian Leukosis Virus; Sensitivity and Specificity; Nanoparticles; Temperature; Polymerase Chain Reaction; Avian Leukosis; Chickens
PubMed: 38275950
DOI: 10.3390/v16010015 -
Microorganisms Dec 2023The Genus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens,...
The Genus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens, contain genetic elements (endogenous retroviruses, ERVs) that could recombine with other alpharetroviruses or express proteins, complementing defective ASLV, which may successfully replicate and cause disease. However, they are quite unknown, and only ALV-F, from ring-necked pheasants, has been partially published. Upon scrutiny of 53 genomes of different avian species, we found -like sequences only in 12 different Galliformes, including six full-length (7.4-7.6 Kbp) and 27 partial sequences. Phylogenetic studies of the regions studied (LTR, , , and ) consistently resulted in five almost identical clades containing the same ERVs: Clade I (presently known ASLVs); Clade II ( spp. ERVs); Clade IIIa ( ERVs); Clade IIIb ( spp. ERVs); and Clade IV ( spp. ERVs). The low identity scores suggested that each of these Clades may be considered a different species. ORF analysis revealed that putatively encoded proteins would be very similar in length and domains to those of other alpharetroviruses and thus potentially functional. This will undoubtedly contribute to better understanding the biology of defective viruses, especially in wild Galliformes, their evolution, and the danger they may represent for other wild species and the poultry industry.
PubMed: 38257913
DOI: 10.3390/microorganisms12010086 -
Journal of Virology Nov 2023The synergy of two oncogenic retroviruses is an essential phenomenon in nature. The synergistic replication of ALV-J and REV in poultry flocks increases...
The synergy of two oncogenic retroviruses is an essential phenomenon in nature. The synergistic replication of ALV-J and REV in poultry flocks increases immunosuppression and pathogenicity, extends the tumor spectrum, and accelerates viral evolution, causing substantial economic losses to the poultry industry. However, the mechanism of synergistic replication between ALV-J and REV is still incompletely elusive. We observed that microRNA-155 targets a dual pathway, PRKCI-MAPK8 and TIMP3-MMP2, interacting with the U3 region of ALV-J and REV, enabling synergistic replication. This work gives us new targets to modulate ALV-J and REV's synergistic replication, guiding future research on the mechanism.
Topics: Animals; Reticuloendotheliosis virus; Avian Leukosis; Avian Leukosis Virus; Chickens; Poultry Diseases; MicroRNAs; Virus Replication
PubMed: 37909729
DOI: 10.1128/jvi.00937-23 -
3'UTR of ALV-J can affect viral replication through promoting transcription and mRNA nuclear export.Journal of Virology Nov 20233'UTRs can affect gene transcription and post-transcriptional regulation in multiple ways, further influencing the function of proteins in a unique manner. Recently,...
3'UTRs can affect gene transcription and post-transcriptional regulation in multiple ways, further influencing the function of proteins in a unique manner. Recently, ALV-J has been mutating and evolving rapidly, especially the 3'UTR of viral genome. Meanwhile, clinical symptoms caused by ALV-J have changed significantly. In this study, we found that the ALV-J strains containing △-r-TM-type 3'UTR are the most abundant. By constructing ALV-J infectious clones and subgenomic vectors containing different 3'UTRs, we prove that 3'UTRs directly affect viral tissue preference and can promote virus replication as an enhancer. ALV-J strain containing 3'UTR of △-r-TM proliferated fastest in primary cells. All five forms of 3'UTRs can assist intron-containing viral mRNA nuclear export, with similar efficiency. ALV-J mRNA half-life is not influenced by different 3'UTRs. Our results dissect the roles of 3'UTR on regulating viral replication and pathogenicity, providing novel insights into potential anti-viral strategies.
Topics: 3' Untranslated Regions; Active Transport, Cell Nucleus; Gene Expression; Gene Expression Regulation; Virus Replication; Avian Leukosis Virus
PubMed: 37902396
DOI: 10.1128/jvi.01152-23 -
Viruses Aug 2023Avian leukosis (AL), caused by avian leukosis virus (ALV), is a contagious tumor disease that results in significant economic losses for the poultry industry. Currently,...
Avian leukosis (AL), caused by avian leukosis virus (ALV), is a contagious tumor disease that results in significant economic losses for the poultry industry. Currently, ALV-A, B, J, and K subgroups are the most common in commercial poultry and cause possible coinfections. Therefore, close monitoring is necessary to avoid greater economic losses. In this study, a novel multiplex quantitative polymerase chain reaction (qPCR) assay was developed to detect ALV-A, ALV-B, ALV-J, and ALV-K with limits of detection of 40, 11, 13.7, and 96 copies/µL, respectively, and no cross-reactivity with other ALV subtypes and avian pathogens. We detected 852 cell cultures inoculated with clinical samples using this method, showing good consistency with conventional PCR and ELISA. The most prevalent ALV strain in Hubei Province, China, was still ALV-J (11.74%). Although single infections with ALV-A, ALV-B, and ALV-K were not found, coinfections with different subgroup strains were identified: 0.7% for ALV-A/J, 0.35% for ALV-B/J, 0.25% for ALV-J/K, and 0.12% for ALV-A/B/K and ALV-A/B/J. Therefore, our novel multiplex qPCR may be a useful tool for molecular epidemiology, clinical detection of ALV, and ALV eradication programs.
Topics: Animals; Avian Leukosis Virus; Coinfection; Avian Leukosis; Cell Culture Techniques; Multiplex Polymerase Chain Reaction
PubMed: 37766196
DOI: 10.3390/v15091789 -
Journal of Virology Aug 2023Avian leukemia virus subgroup J (ALV-J) causes various diseases associated with tumor formation and decreased fertility and induced immunosuppressive disease, resulting...
Avian leukemia virus subgroup J (ALV-J) causes various diseases associated with tumor formation and decreased fertility and induced immunosuppressive disease, resulting in significant economic losses in the poultry industry globally. Virus usually exploits the host cellular machinery for their replication. Although there are increasing evidences for the cellular proteins involving viral replication, the interaction between ALV-J and host proteins leading to the pivotal steps of viral life cycle are still unclear. Here, we reported that ribonucleoside-diphosphate reductase subunit M2 (RRM2) plays a critical role during ALV-J infection by interacting with capsid protein P27 and activating Wnt/β-catenin signaling. We found that the expression of RRM2 is effectively increased during ALV-J infection, and that RRM2 facilitates ALV-J replication by interacting with viral capsid protein P27. Furthermore, ALV-J P27 activated Wnt/β-catenin signaling by promoting β-catenin entry into the nucleus, and RRM2 activated Wnt/β-catenin signaling by enhancing its phosphorylation at Ser18 during ALV-J infection. These data suggest that the upregulation of RRM2 expression by ALV-J infection favors viral replication in host cells via activating Wnt/β-catenin signaling. IMPORTANCE Our results revealed a novel mechanism by which RRM2 facilitates ALV-J growth. That is, the upregulation of RRM2 expression by ALV-J infection favors viral replication by interacting with capsid protein P27 and activating Wnt/β-catenin pathway in host cells. Furthermore, the phosphorylation of serine at position 18 of RRM2 was verified to be the important factor regulating the activation of Wnt/β-catenin signaling. This study provides insights for further studies of the molecular mechanism of ALV-J infection.
Topics: Animals; Avian Leukosis; Avian Leukosis Virus; beta Catenin; Capsid Proteins; Chickens; Wnt Signaling Pathway; Ribonucleoside Diphosphate Reductase
PubMed: 37582207
DOI: 10.1128/jvi.00267-23 -
The Journal of Biological Chemistry Jun 2023Integration of retroviral DNA into the host genome involves the formation of integrase (IN)-DNA complexes termed intasomes. Further characterization of these complexes...
Integration of retroviral DNA into the host genome involves the formation of integrase (IN)-DNA complexes termed intasomes. Further characterization of these complexes is needed to understand their assembly process. Here, we report the single-particle cryo-EM structure of the Rous sarcoma virus (RSV) strand transfer complex (STC) intasome produced with IN and a preassembled viral/target DNA substrate at 3.36 Å resolution. The conserved intasome core region consisting of IN subunits contributing active sites interacting with viral/target DNA has a resolution of 3 Å. Our structure demonstrated the flexibility of the distal IN subunits relative to the IN subunits in the conserved intasome core, similar to results previously shown with the RSV octameric cleaved synaptic complex intasome produced with IN and viral DNA only. An extensive analysis of higher resolution STC structure helped in the identification of nucleoprotein interactions important for intasome assembly. Using structure-function studies, we determined the mechanisms of several IN-DNA interactions critical for assembly of both RSV intasomes. We determined the role of IN residues R244, Y246, and S124 in cleaved synaptic complex and STC intasome assemblies and their catalytic activities, demonstrating differential effects. Taken together, these studies advance our understanding of different RSV intasome structures and molecular determinants involved in their assembly.
Topics: DNA, Viral; Integrases; Rous sarcoma virus; Virus Integration; Cryoelectron Microscopy
PubMed: 37084813
DOI: 10.1016/j.jbc.2023.104730 -
Microbiology Spectrum Jun 2023Glycogen synthase kinase 3β (GSK3β) is a widely distributed multifunctional serine/threonine kinase. In mammals, GSK3β regulates important life activities such as...
Glycogen synthase kinase 3β (GSK3β) is a widely distributed multifunctional serine/threonine kinase. In mammals, GSK3β regulates important life activities such as proinflammatory response, anti-inflammatory response, immunity, and cancer development. However, the biological functions of chicken GSK3β (chGSK3β) are still unknown. In the present study, the full-length cDNA of chGSK3β was first cloned and analyzed. Absolute quantification of chicken chGSK3β in 1-day-old specific-pathogen-free birds has shown that it is widely expressed in all tissues, with the highest level in brain and the lowest level in pancreas. Overexpression of chGSK3β in DF-1 cells significantly decreased the gene expression levels of interferon beta (IFN-β), IFN regulatory factor 7 (IRF7), Toll-like receptor 3 (TLR3), melanoma differentiation-associated protein 5 (MDA5), MX-1, protein kinase R (PKR), and oligoadenylate synthase-like (OASL), while promoting the replication of avian leukosis virus subgroup J (ALV-J). Conversely, levels of most of the genes detected in this study were increased when chGSK3β expression was knocked down using small interfering RNA (siRNA), which also inhibited the replication of ALV-J. These results suggest that chGSK3β plays an important role in the antiviral innate immune response in DF-1 cells, and it will be valuable to carry out further studies on the biological functions of chGSK3β. GSK3β regulates many life activities in mammals. Recent studies revealed that chGSK3β was involved in regulating antiviral innate immunity in DF-1 cells and also could positively regulate ALV-J replication. These results provide new insights into the biofunction of chGSK3β and the virus-host interactions of ALV-J. In addition, this study provides a basis for further research on the function of GSK3 in poultry.
Topics: Animals; Chickens; Avian Leukosis Virus; Glycogen Synthase Kinase 3 beta; Glycogen Synthase Kinase 3; Immunity, Innate; Antiviral Agents; Poultry Diseases; Mammals
PubMed: 36995259
DOI: 10.1128/spectrum.05235-22