1
|
Chacón RD, Sánchez-Llatas CJ, L Pajuelo S, Diaz Forero AJ, Jimenez-Vasquez V, Médico JA, Soto-Ugaldi LF, Astolfi-Ferreira CS, Piantino Ferreira AJ. Molecular characterization of the meq oncogene of Marek's disease virus in vaccinated Brazilian poultry farms reveals selective pressure on prevalent strains. Vet Q 2024; 44:1-13. [PMID: 38465827 DOI: 10.1080/01652176.2024.2318198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 02/05/2024] [Indexed: 03/12/2024] Open
Abstract
Marek's disease virus (MDV) has become an increasingly virulent pathogen in the poultry industry despite vaccination efforts to control it. Brazil has experienced a significant rise of Marek's disease (MD) outbreaks in recent years. Our study aimed to analyze the complete meq gene sequences to understand the molecular epidemiological basis of MD outbreaks in Brazilian vaccinated layer farms. We detected a high incidence rate of visceral MD (67.74%) and multiple circulating MDV strains. The most prevalent and geographically widespread genotype presented several clinical and molecular characteristics of a highly virulent strain and evolving under positive selective pressure. Phylogenetic and phylogeographic analysis revealed a closer relationship with strains from the USA and Japan. This study sheds light on the circulation of MDV strains capable of infecting vaccinated birds. We emphasize the urgency of adopting preventive measures to manage MDV outbreaks threatening the poultry farming industry.
Collapse
Affiliation(s)
- Ruy D Chacón
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Christian J Sánchez-Llatas
- Department of Genetics, Physiology, and Microbiology, Faculty of Biology, Complutense University of Madrid, Madrid, Spain
| | | | - Andrea J Diaz Forero
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | | | - Jack A Médico
- Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA
| | - Luis F Soto-Ugaldi
- Tri-Institutional Program in Computational Biology and Medicine, New York, NY, USA
| | | | | |
Collapse
|
2
|
Cheng MC, Lai GH, Tsai YL, Lien YY. Circulating hypervirulent Marek's disease viruses in vaccinated chicken flocks in Taiwan by genetic analysis of meq oncogene. PLoS One 2024; 19:e0303371. [PMID: 38728352 PMCID: PMC11086920 DOI: 10.1371/journal.pone.0303371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 04/23/2024] [Indexed: 05/12/2024] Open
Abstract
Marek's disease (MD) is an important neoplastic disease caused by serotype 1 Marek's disease virus (MDV-1), which results in severe economic losses worldwide. Despite vaccination practices that have controlled the MD epidemic, current increasing MD-suspected cases indicate the persistent viral infections circulating among vaccinated chicken farms in many countries. However, the lack of available information about phylogeny and molecular characterization of circulating MDV-1 field strains in Taiwan reveals a potential risk in MD outbreaks. This study investigated the genetic characteristics of 18 MDV-1 strains obtained from 17 vaccinated chicken flocks in Taiwan between 2018 and 2020. Based on the sequences of the meq oncogene, the phylogenetic analysis demonstrated that the circulating Taiwanese MDV-1 field strains were predominantly in a single cluster that showed high similarity with strains from countries of the East Asian region. Because the strains were obtained from CVI988/Rispens vaccinated chicken flocks and the molecular characteristics of the Meq oncoprotein showed features like vvMDV and vv+MDV strains, the circulating Taiwanese MDV-1 field strains may have higher virulence compared with vvMDV pathotype. In conclusion, the data presented demonstrates the circulation of hypervirulent MDV-1 strains in Taiwan and highlights the importance of routine surveillance and precaution strategies in response to the emergence of enhanced virulent MDV-1.
Collapse
Affiliation(s)
- Ming-Chu Cheng
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Animal Disease Diagnostic Center, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center of Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Guan-Hua Lai
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Animal Disease Diagnostic Center, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center of Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Yi-Lun Tsai
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Yi-Yang Lien
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Animal Disease Diagnostic Center, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center of Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| |
Collapse
|
3
|
Davidson I, Lupini C, Catelli E, Quaglia G, Maddaloni L, Mescolini G. Virulence evaluation of Israeli Marek's disease virus isolates from commercial poultry using their meq gene sequence. Virus Genes 2024; 60:32-43. [PMID: 38184501 DOI: 10.1007/s11262-023-02042-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 11/17/2023] [Indexed: 01/08/2024]
Abstract
Fifty-seven Gallid alphaherpesvirus 2 (GaHV-2) isolates, collected during a 30-year period (1990-2019) from commercial poultry flocks affected by Marek's disease (MD), were molecularly characterised. The GaHV-2 meq gene was amplified and sequenced to evaluate the virus virulence, based on the number of PPPPs within the proline-rich repeats (PRRs) of its transactivation domain. The present illustration of virus virulence evaluation on a large scale of field virus isolates by molecular analysis exemplifies the practical benefit and usefulness of the molecular marker in commercial GaVH-2 isolates. The alternative assay of GaVH-2 virulence pathotyping is the classical Gold Standard ADOL method, which is difficult and impossible to employ on a large scale using the Specific Pathogen Free (SPF) chicks of the ADOL strains kept in isolators for two months. The phylogenetic analysis performed in the present study showed that the meq gene amino acid sequences of the 57 Israeli strains divide into 16 phylogenetic branches. The virulence evaluation was performed in comparison with 36 GaHV-2 prototype strains, previously characterised by the in vivo Gold Standard ADOL assay. The results obtained revealed that the GaHV-2 strains circulating in Israel have evolved into a higher virulence potential during the years, as the four-proline stretches number in the meq gene decreased over the investigated period, typically of very virulent virus prototypes. The present study supports the meq gene molecular markers for the assessment of field GaVH-2 strains virulence.
Collapse
Affiliation(s)
| | - Caterina Lupini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Bologna, Italy
| | - Elena Catelli
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Bologna, Italy
| | - Giulia Quaglia
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Bologna, Italy
| | - Luca Maddaloni
- Department of Public Health and Infectious Diseases, Sapienza, University of Rome, Rome, Italy
| | - Giulia Mescolini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Bologna, Italy
- Operating Unit of Animal Health and Hygiene of Livestock Production, Department of Public Health, AUSL della Romagna, Forlì, FC, Italy
| |
Collapse
|
4
|
Žlabravec Z, Slavec B, Rožmanec E, Koprivec S, Dovč A, Zorman Rojs O. First Report of Marek's Disease Virus in Commercial Turkeys in Slovenia. Animals (Basel) 2024; 14:250. [PMID: 38254418 PMCID: PMC10812425 DOI: 10.3390/ani14020250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/09/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Marek's disease (MD), caused by Mardivirus gallidalpha 2 (GaAHV-2), also known as MD virus (MDV), is a lymphoproliferative disease that primarily affects chickens. Recently, MDV has been detected in lymphomatous tumors in turkeys in various countries. Between 2021 and 2023, three cases ranging from no to severe clinical disorders (depression, lameness, and increased mortality) occurred in commercial turkey flocks in Slovenia. In all cases, MDV was detected by PCR in DNA samples extracted from organs developing tumor infiltrations. Sequencing and phylogenetic analysis of the meq gene revealed that the GaAHV-2 detected has molecular features of a very virulent pathotype and genetic similarity with GaAHV-2 detected in chickens in Tunisia. This is the first report of MDV in commercial turkeys in Slovenia.
Collapse
Affiliation(s)
- Zoran Žlabravec
- Institute of Poultry, Birds, Small Mammals, and Reptiles, Faculty of Veterinary Medicine, University of Ljubljana, Gerbičeva ulica 60, 1000 Ljubljana, Slovenia; (Z.Ž.)
| | - Brigita Slavec
- Institute of Poultry, Birds, Small Mammals, and Reptiles, Faculty of Veterinary Medicine, University of Ljubljana, Gerbičeva ulica 60, 1000 Ljubljana, Slovenia; (Z.Ž.)
| | - Ema Rožmanec
- Veterinarska Ambulanta PP, d.o.o., Potrčeva cesta 10, 2250 Ptuj, Slovenia
| | - Saša Koprivec
- Institute of Preclinical Sciences, Faculty of Veterinary Medicine, University of Ljubljana, Gerbičeva ulica 60, 1000 Ljubljana, Slovenia
| | - Alenka Dovč
- Institute of Poultry, Birds, Small Mammals, and Reptiles, Faculty of Veterinary Medicine, University of Ljubljana, Gerbičeva ulica 60, 1000 Ljubljana, Slovenia; (Z.Ž.)
| | - Olga Zorman Rojs
- Institute of Poultry, Birds, Small Mammals, and Reptiles, Faculty of Veterinary Medicine, University of Ljubljana, Gerbičeva ulica 60, 1000 Ljubljana, Slovenia; (Z.Ž.)
| |
Collapse
|
5
|
Davidson I. Avian Oncogenic and Immunosuppressive Viruses. Infect Dis (Lond) 2023. [DOI: 10.1007/978-1-0716-2463-0_1091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
|
6
|
Sun A, Zhao X, Zhu X, Kong Z, Liao Y, Teng M, Yao Y, Luo J, Nair V, Zhuang G, Zhang G. Fully Attenuated meq and pp38 Double Gene Deletion Mutant Virus Confers Superior Immunological Protection against Highly Virulent Marek's Disease Virus Infection. Microbiol Spectr 2022; 10:e0287122. [PMID: 36350141 PMCID: PMC9769808 DOI: 10.1128/spectrum.02871-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/17/2022] [Indexed: 11/11/2022] Open
Abstract
Marek's disease virus (MDV) induces immunosuppression and neoplastic disease in chickens. The virus is controllable via an attenuated meq deletion mutant virus, which has the disadvantage of retaining the ability to induce lymphoid organ atrophy. To overcome this deficiency and produce more vaccine candidates, a recombinant MDV was generated from the highly virulent Md5BAC strain, in which both meq and a cytolytic replication-related gene, pp38, were deleted. Replication of the double deletion virus, Md5BAC ΔmeqΔpp38, was comparable with that of the parental virus in vitro. The double deletion virus was shown to be fully attenuated and to reduce lymphoid organ atrophy in vivo. Crucially, Md5BAC ΔmeqΔpp38 confers superior protection against highly virulent virus compared with a commercial vaccine strain, CVI988/Rispens. Transcriptomic profiling indicated that Md5BAC ΔmeqΔpp38 induced a different host immune response from CVI988/Rispens. In summary, a novel, effective, and safe vaccine candidate for prevention and control of MD caused by highly virulent MDV is reported. IMPORTANCE MDV is a highly contagious immunosuppressive and neoplastic pathogen. The virus can be controlled through vaccination via an attenuated meq deletion mutant virus that retains the ability to induce lymphoid organ atrophy. In this study, we overcame the deficiency by generating meq and pp38 double deletion mutant virus. Indeed, the successfully generated meq and pp38 double deletion mutant virus had significantly reduced replication capacity in vivo but not in vitro. It was fully attenuated and conferred superior protection efficacy against very virulent MDV challenge. In addition, the possible immunological protective mechanism of the double deletion mutant virus was shown to be different from that of the gold standard MDV vaccine, CVI988/Rispens. Overall, we successfully generated an attenuated meq deletion mutant virus and widened the range of potential vaccine candidates. Importantly, this study provides for the first time the theoretical basis of vaccination induced by fully attenuated gene-deletion mutant virus.
Collapse
Affiliation(s)
- Aijun Sun
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
| | - Xuyang Zhao
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
| | - Xiaojing Zhu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
| | - Zhengjie Kong
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
| | - Yifei Liao
- Division of Infectious Disease, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Man Teng
- Key Laboratory of Animal Immunology, Ministry of Agriculture and Rural Affairs & Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
- UK-China Centre of Excellence for Research on Avian Diseases, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
| | - Yongxiu Yao
- Viral Oncogenesis Group,The Pirbright Institute, Pirbright, Surrey, United Kingdom
- UK-China Centre of Excellence for Research on Avian Diseases, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Jun Luo
- Key Laboratory of Animal Immunology, Ministry of Agriculture and Rural Affairs & Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
- UK-China Centre of Excellence for Research on Avian Diseases, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
| | - Venugopal Nair
- Viral Oncogenesis Group,The Pirbright Institute, Pirbright, Surrey, United Kingdom
- UK-China Centre of Excellence for Research on Avian Diseases, The Pirbright Institute, Pirbright, Surrey, United Kingdom
| | - Guoqing Zhuang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
| | - Gaiping Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- International Joint Research Center of National Animal Immunology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, People’s Republic of China
- Key Laboratory of Animal Immunology, Ministry of Agriculture and Rural Affairs & Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
- UK-China Centre of Excellence for Research on Avian Diseases, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, People’s Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou, People’s Republic of China
| |
Collapse
|
7
|
Wannaratana S, Tunterak W, Prakairungnamthip D, Sasipreeyajan J, Thontiravong A. Genetic characterization of Marek's disease virus in chickens in Thailand reveals a high genetic diversity of circulating strains. Transbound Emerg Dis 2022; 69:3771-3779. [PMID: 36315934 DOI: 10.1111/tbed.14748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/09/2022] [Accepted: 10/27/2022] [Indexed: 11/13/2022]
Abstract
Marek's disease (MD) is a highly contagious lymphoproliferative disease of chickens caused by Gallid alphaherpesvirus 2, commonly known as serotype 1 Marek's disease virus (MDV-1). Despite widespread vaccination, MD-related cases have been frequently observed worldwide, including in Thailand. However, no information is available on the genetic characteristics of MDV-1 field strains circulating in chickens in Thailand. This study investigated the geographic distribution and genetic characteristics of MDV-1 field strains circulating in chickens in Thailand between 2013 and 2021 by analysing the Meq and pp38 genes. Out of a total of the 286 clinical samples obtained from 70 chicken farms located in major chicken raising areas of Thailand, 138 samples (48.25%) from 46 chicken farms (65.71%) tested positive for MDV-1 field strains. Results demonstrated that MDV-1 field strains were extensively distributed in major chicken raising areas. Phylogenetic analyses based on the Meq gene revealed that four clusters of MDV-1 circulated in chickens in Thailand between 2013 and 2021. Among these clusters, cluster 1 was the predominant cluster circulating in chickens in Thailand. Additionally, our findings based on molecular characteristics of Meq and pp38 gene/protein suggested that most of the Thai MDV-1 field strains were potentially highly virulent. In conclusion, our data demonstrated the circulation of different clusters of MDV-1 with virulence characteristics in chickens in Thailand, indicating high genetic diversity of MDV-1 in Thailand. This study highlights the importance of more effective vaccine development and routine MDV-1 surveillance for early detection and control of highly virulent MDV-1.
Collapse
Affiliation(s)
- Suwarak Wannaratana
- Faculty of Veterinary Medicine, Rajamangala University of Technology Tawan-Ok, Bang Phra, Chonburi, Thailand
| | - Wikanda Tunterak
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Duangduean Prakairungnamthip
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Jiroj Sasipreeyajan
- Avian Health Research Unit, Department of Veterinary Medicine, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Aunyaratana Thontiravong
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.,Center of Excellence for Emerging and Re-emerging Infectious Diseases in Animals (CUEIDAs), Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.,Animal Vector-Borne Disease Research Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.,Research Unit of Systems Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| |
Collapse
|
8
|
Bayoumi M, El-Saied M, Ahmed B, El-Mahdy M, Amer H. Gallid Alphaherpesvirus 2 in the Egyptian Turkeys: Molecular Characterization and Establishment of a Universal System for Phylogenetic Classification. Intervirology 2021; 64:156-164. [PMID: 34023833 DOI: 10.1159/000515904] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 03/16/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Gallid alphaherpesvirus 2 (GaHV-2) is a highly contagious oncogenic virus that causes Marek's disease in chickens and occasionally in turkeys. Among 100 genes identified in GaHV-2 genome, the Meq gene appears to involve viral virulence, oncogenicity, and genetic diversity. Despite the use of Meq gene sequences in phylogenetic classification of GaHV-2 strains circulating in many countries worldwide, no integrated system exists yet. METHODS Turkeys from 2 commercial Egyptian farms were presented with signs of dullness, dehydration, and emaciation. Samples prepared from the internal organs were examined by histopathology and immunohistochemistry. Pools of the internal organs were analyzed by PCR for identification of GaHV-2, avian leucosis virus, and reticuloendotheliosis virus. The Meq gene of an Egyptian strain was sequenced and analyzed in comparison to 40 reference strains for generation of a universal system for phylogenetic classification of GaHV-2 strains. RESULTS Gross and histopathological examination revealed grayish-white soft masses in the internal organs characterized by diffuse infiltration of pleomorphic neoplastic cells. All lymphoma cells were identified as T-lymphocytes of CD3+ phenotype. Samples of both farms were only positive for GaHV-2 by PCR. Sequence analysis of the Meq gene has classified the current turkey strain as related to the Egyptian strains identified in chicken in 2012. A universal phylogenetic system for classification of GaHV-2 strains into 4 clusters was proposed. The vaccine strains were all grouped in cluster 2, and most of the classical American strains belonged to cluster 4. Cluster 1 was further divided into 3 subclusters (1.1-1.3). CONCLUSION GaHV-2 was identified in turkeys for the first time in Africa and the Middle East. Sequence analysis of the Meq gene of the Egyptian strain along with a wide array of the global strains has enabled the construction of a novel phylogenetic classification system.
Collapse
Affiliation(s)
- Mahmoud Bayoumi
- Virology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.,Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
| | - Mohamed El-Saied
- Pathology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Basem Ahmed
- Virology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Magdy El-Mahdy
- Pathology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Haitham Amer
- Virology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| |
Collapse
|
9
|
Ozan E, Muftuoglu B, Sahindokuyucu I, Kurucay HN, Inal S, Kuruca N, Elhag AE, Karaca E, Tamer C, Gumusova S, Albayrak H, Barry G, Gulbahar MY, Yazici Z. Marek's disease virus in vaccinated poultry flocks in Turkey: its first isolation with molecular characterization. Arch Virol 2021; 166:559-569. [PMID: 33409548 DOI: 10.1007/s00705-020-04943-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/15/2020] [Indexed: 12/28/2022]
Abstract
Marek's disease (MD) is an important disease of avian species and a potential threat to the poultry industry worldwide. In this study, 16 dead commercial chickens from flocks with suspected MD were necropsied immediately after death. Pathological findings were compatible with MD, and gallid alphaherpesvirus 2 was identified in PCR of spleen samples. Virus isolation was performed in primary cell culture, and partial sequencing of the meq gene of the isolate revealed >99% nucleotide sequence identity to virulent and very virulent plus strains from a number of European countries, placing it in the same subclade of clade III as two virulent Italian strains and a very virulent plus Polish strain as well as virulent strains of geese and ducks. The data reported here indicate that a virulent strain of Marek's disease virus is circulating in Turkey and has not been stopped by the current national vaccination programme.
Collapse
Affiliation(s)
- Emre Ozan
- Department of Veterinary Experimental Animals, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey.
| | - Bahadir Muftuoglu
- Department of Veterinary Experimental Animals, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Ismail Sahindokuyucu
- Bornova Veterinary Control Institute, Veterinary Control Institute Directorates, Ministry of Agriculture and Forestry, 35010, Izmir, Turkey
| | - Hanne Nur Kurucay
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Sinem Inal
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Nilufer Kuruca
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Ahmed Eisa Elhag
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Efe Karaca
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Cuneyt Tamer
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Semra Gumusova
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Harun Albayrak
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Gerald Barry
- Veterinary Science Centre, School of Veterinary Medicine, University College of Dublin, Belfield, Dublin 4, Ireland
| | - Mustafa Yavuz Gulbahar
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| | - Zafer Yazici
- Department of Veterinary Virology, Faculty of Veterinary Medicine, Ondokuz Mayis University, 55139, Atakum, Samsun, Turkey
| |
Collapse
|
10
|
Conradie AM, Bertzbach LD, Trimpert J, Patria JN, Murata S, Parcells MS, Kaufer BB. Distinct polymorphisms in a single herpesvirus gene are capable of enhancing virulence and mediating vaccinal resistance. PLoS Pathog 2020; 16:e1009104. [PMID: 33306739 PMCID: PMC7758048 DOI: 10.1371/journal.ppat.1009104] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 12/23/2020] [Accepted: 10/27/2020] [Indexed: 12/14/2022] Open
Abstract
Modified-live herpesvirus vaccines are widely used in humans and animals, but field strains can emerge that have a higher virulence and break vaccinal protection. Since the introduction of the first vaccine in the 1970s, Marek’s disease virus overcame the vaccine barrier by the acquisition of numerous genomic mutations. However, the evolutionary adaptations in the herpesvirus genome responsible for the vaccine breaks have remained elusive. Here, we demonstrate that point mutations in the multifunctional meq gene acquired during evolution can significantly alter virulence. Defined mutations found in highly virulent strains also allowed the virus to overcome innate cellular responses and vaccinal protection. Concomitantly, the adaptations in meq enhanced virus shedding into the environment, likely providing a selective advantage for the virus. Our study provides the first experimental evidence that few point mutations in a single herpesviral gene result in drastically increased virulence, enhanced shedding, and escape from vaccinal protection. Viruses can acquire mutations during evolution that alter their virulence. An example of a virus that has shown repeated shifts to higher virulence in response to more efficacious vaccines is the oncogenic Marek’s disease virus (MDV) that infects chickens. Until now, it remained unknown which mutations in the large virus genome are responsible for this increase in virulence. We could demonstrate that very few amino acid changes in the meq oncogene of MDV can significantly alter the virulence of the virus. In addition, these changes also allow the virus to overcome vaccinal protection and enhance the shedding into the environment. Taken together, our data provide fundamental insights into evolutionary changes that allow this deadly veterinary pathogen to evolve towards greater virulence.
Collapse
Affiliation(s)
| | | | - Jakob Trimpert
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
| | - Joseph N. Patria
- Department of Biological Sciences, University of Delaware, Newark, United States of America
| | - Shiro Murata
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Mark S. Parcells
- Department of Animal and Food Sciences, University of Delaware, Newark, United States of America
| | - Benedikt B. Kaufer
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
- * E-mail:
| |
Collapse
|
11
|
Occurrence of Marek's Disease in Poland on the Basis of Diagnostic Examination in 2015-2018. J Vet Res 2020; 64:503-507. [PMID: 33367138 PMCID: PMC7734681 DOI: 10.2478/jvetres-2020-0079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 11/17/2020] [Indexed: 01/12/2023] Open
Abstract
Introduction Marek’s disease (MD) is a tumourous disease caused by Marek’s disease virus (MDV) and most commonly described in poultry. The aim of the study was to determine the occurrence of Marek’s disease virus infections in Poland and analyse clinical cases in the years 2015–2018. Material and Methods The birds for diagnostic examination originated from 71 poultry flocks of various types of production. Birds were subjected to anatomopathological examination post mortem, during which liver and spleen sections and other pathologically changed internal organs were taken. These sections were homogenised with generally accepted methods, then total DNA was isolated and amplified with a real-time PCR. A pair of primers complementary to the MDV genome region encoding the meq gene were used. Results MDV infection was found predominantly in broiler chicken flocks (69.01%), and also in layer breeder (9.85%) and commercial layer flocks (7.04% each). Conclusion The results of research conducted in the years 2015–2018 clearly indicate that the problem of MDV infections is still current.
Collapse
|
12
|
Murata S, Machida Y, Isezaki M, Maekawa N, Okagawa T, Konnai S, Ohashi K. Genetic characterization of a Marek's disease virus strain isolated in Japan. Virol J 2020; 17:186. [PMID: 33228722 PMCID: PMC7684920 DOI: 10.1186/s12985-020-01456-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/15/2020] [Indexed: 01/29/2023] Open
Abstract
Background Marek’s disease virus (MDV) causes malignant lymphomas in chickens (Marek’s disease, MD). MD is currently controlled by vaccination; however, MDV strains have a tendency to develop increased virulence. Distinct diversity and point mutations are present in the Meq proteins, the oncoproteins of MDV, suggesting that changes in protein function induced by amino acid substitutions might affect MDV virulence. We previously reported that recent MDV isolates in Japan display distinct mutations in Meq proteins from those observed in traditional MDV isolates in Japan, but similar to those in MDV strains isolated from other countries. Methods To further investigate the genetic characteristics in Japanese field strains, we sequenced the whole genome of an MDV strain that was successfully isolated from a chicken with MD in Japan. A phylogenetic analysis of the meq gene was also performed. Results Phylogenetic analysis revealed that the Meq proteins in most of the Japanese isolates were similar to those of Chinese and European strains, and the genomic sequence of the Japanese strain was classified into the Eurasian cluster. Comparison of coding region sequences among the Japanese strain and MDV strains from other countries revealed that the genetic characteristics of the Japanese strain were similar to those of Chinese and European strains. Conclusions The MDV strains distributed in Asian and European countries including Japan seem to be genetically closer to each other than to MDV strains from North America. These findings indicate that the genetic diversities of MDV strains that emerged may have been dependent on the different vaccination-based control approaches.
Collapse
Affiliation(s)
- Shiro Murata
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan. .,Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan.
| | - Yuka Machida
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| | - Masayoshi Isezaki
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| | - Naoya Maekawa
- Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| | - Tomohiro Okagawa
- Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| | - Satoru Konnai
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan.,Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| | - Kazuhiko Ohashi
- Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan.,Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Japan
| |
Collapse
|
13
|
Davidson I. Out of Sight, but Not Out of Mind: Aspects of the Avian Oncogenic Herpesvirus, Marek's Disease Virus. Animals (Basel) 2020; 10:E1319. [PMID: 32751762 PMCID: PMC7459476 DOI: 10.3390/ani10081319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 02/08/2023] Open
Abstract
Marek's disease virus is an economically important avian herpesvirus that causes tumors and immunosuppression in chickens and turkeys. The virus, disease, and vaccines have been known for more than 50 years, but as knowledge gaps still exists, intensive research is still ongoing. The understanding of MDV complexity can provide scientific insight in topics that cannot be experimented in humans, providing a unique model that is dually useful for the benefit of the poultry industry and for studying general herpesvirology. The present review presents the following topics: the MDV biology, the vaccine's and virulent virus' peculiar presence in feathers, protection by vaccination. In addition, two relatively behind the scenes topics are reviewed; first, the meq MDV oncogene and its recent implication in molecular epidemiology and in the MDV virulence determination, and second, the functionality of conformational epitopes of the MDV immunodominant protein, glycoprotein B. Our studies were particular, as they were the only ones describing three-dimensional MDV gB oligomers. MDV gB (glycoprotein B) continuous and discontinuous epitopes were shown to possess distinctive neutralization activities. In contrast, the significance of oligomerization of the viral membrane proteins for the creation of discontinuous epitopes in other herpesviruses was explored extensively.
Collapse
Affiliation(s)
- Irit Davidson
- Division of Avian Diseases, Kimron Veterinary Institute, Bet Dagan 50250, Israel
| |
Collapse
|
14
|
Mescolini G, Lupini C, Davidson I, Massi P, Tosi G, Fiorentini L, Catelli E. Molecular characterization of a Marek's disease virus strain detected in tumour-bearing turkeys. Avian Pathol 2019; 49:202-207. [PMID: 31702386 DOI: 10.1080/03079457.2019.1691715] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Marek's disease (MD) is a lymphoproliferative disease caused by Gallid alphaherpesvirus 2 (GaHV-2), which primarily affects chickens. However, the virus is also able to induce tumours in turkeys, albeit less frequently than in chickens. This study reports the molecular characterization of a GaHV-2 strain detected in a flock of Italian meat-type turkeys exhibiting visceral lymphomas. Sequencing and phylogenetic analysis of the meq gene revealed that the turkey GaHV-2 has molecular features of high virulence and genetic similarity with GaHV-2 strains recently detected in Italian commercial and backyard chickens. GaHV-2 is ubiquitous among chickens despite vaccination, and chicken-to-turkey transmission is hypothesized due to the presence of broilers in neighbouring pens.RESEARCH HIGHLIGHTS A GaHV-2 strain from Italian turkeys was molecularly characterized.The turkey strain presented molecular characteristics of high virulence in its meq gene.The turkey strain was closely related to previously detected chicken strains.
Collapse
Affiliation(s)
- Giulia Mescolini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, BO, Italy
| | - Caterina Lupini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, BO, Italy
| | - Irit Davidson
- Division of Avian Diseases, Kimron Veterinary Institute, Bet Dagan, Israel
| | - Paola Massi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Sezione Diagnostica di Forlì, Forlì, FC, Italy
| | - Giovanni Tosi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Sezione Diagnostica di Forlì, Forlì, FC, Italy
| | - Laura Fiorentini
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Sezione Diagnostica di Forlì, Forlì, FC, Italy
| | - Elena Catelli
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, BO, Italy
| |
Collapse
|