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Pluta A, Jaworski JP, Droscha C, VanderWeele S, Taxis TM, Valas S, Brnić D, Jungić A, Ruano MJ, Sánchez A, Murakami K, Nakamura K, Puentes R, De Brun ML, Ruiz V, Gómez MEL, Lendez P, Dolcini G, Camargos MF, Fonseca A, Barua S, Wang C, Giza A, Kuźmak J. Inter-laboratory comparison of eleven quantitative or digital PCR assays for detection of proviral bovine leukemia virus in blood samples. BMC Vet Res 2024; 20:381. [PMID: 39187880 DOI: 10.1186/s12917-024-04228-z] [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: 11/24/2023] [Accepted: 08/09/2024] [Indexed: 08/28/2024] Open
Abstract
Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis and causes a persistent infection that can leave cattle with no symptoms. Many countries have been able to successfully eradicate BLV through improved detection and management methods. However, with the increasing novel molecular detection methods there have been few efforts to standardize these results at global scale. This study aimed to determine the interlaboratory accuracy and agreement of 11 molecular tests in detecting BLV. Each qPCR/ddPCR method varied by target gene, primer design, DNA input and chemistries. DNA samples were extracted from blood of BLV-seropositive cattle and lyophilized to grant a better preservation during shipping to all participants around the globe. Twenty nine out of 44 samples were correctly identified by the 11 labs and all methods exhibited a diagnostic sensitivity between 74 and 100%. Agreement amongst different assays was linked to BLV copy numbers present in samples and the characteristics of each assay (i.e., BLV target sequence). Finally, the mean correlation value for all assays was within the range of strong correlation. This study highlights the importance of continuous need for standardization and harmonization amongst assays and the different participants. The results underscore the need of an international calibrator to estimate the efficiency (standard curve) of the different assays and improve quantitation accuracy. Additionally, this will inform future participants about the variability associated with emerging chemistries, methods, and technologies used to study BLV. Altogether, by improving tests performance worldwide it will positively aid in the eradication efforts.
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Affiliation(s)
- Aneta Pluta
- Department of Biochemistry, National Veterinary Research Institute, Puławy, 24-100, Poland.
- Department of Omics Analyses, National Veterinary Research Institute, 24-100, Puławy, Poland.
| | - Juan Pablo Jaworski
- Instituto de Virología E Innovaciones Tecnológicas (IVIT), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas (CICVyA), Instituto Nacional de Tecnología Agropecuaria (INTA) - CONICET, Buenos Aires, Argentina
| | - Casey Droscha
- CentralStar Cooperative, 4200 Forest Rd, Lansing, MI, 48910, USA
| | | | - Tasia M Taxis
- Department of Animal Science, College of Agriculture and Natural Resources, Michigan State University, East Lansing, Michigan, 48824, USA
| | - Stephen Valas
- Niort Laboratory, Unit Pathology and Welfare of Ruminants, French Agency for Food, Environmental and Occupational Health and Safety (Anses), Ploufragan-Plouzané, Niort, France
| | - Dragan Brnić
- Croatian Veterinary Institute, Savska Cesta 143, Zagreb, 10000, Croatia
| | - Andreja Jungić
- Croatian Veterinary Institute, Savska Cesta 143, Zagreb, 10000, Croatia
| | - María José Ruano
- Laboratorio Central de Veterinaria (LCV), Ministry of Agriculture, Fisheries and Food, Carretera M-106 (Km 1,4), Madrid, Algete, 28110, Spain
| | - Azucena Sánchez
- Laboratorio Central de Veterinaria (LCV), Ministry of Agriculture, Fisheries and Food, Carretera M-106 (Km 1,4), Madrid, Algete, 28110, Spain
| | - Kenji Murakami
- Department of Veterinary Sciences, Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, 020-8550, Japan
| | - Kurumi Nakamura
- Department of Veterinary Sciences, Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, 020-8550, Japan
| | - Rodrigo Puentes
- Departamento de Patobiología, Facultad de Veterinaria, Unidad de Microbiología, Universidad de La República, Ruta 8, Km 18, Montevideo, 13000, Uruguay
| | - MLaureana De Brun
- Departamento de Patobiología, Facultad de Veterinaria, Unidad de Microbiología, Universidad de La República, Ruta 8, Km 18, Montevideo, 13000, Uruguay
| | - Vanesa Ruiz
- Instituto de Virología E Innovaciones Tecnológicas (IVIT), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas (CICVyA), Instituto Nacional de Tecnología Agropecuaria (INTA) - CONICET, Buenos Aires, Argentina
| | - Marla Eliana Ladera Gómez
- Laboratorio de Virología, Departamento SAMP, Centro de Investigación Veterinaria de Tandil-CIVETAN (CONICET/UNCPBA/CICPBA), Buenos Aires, Argentina
| | - Pamela Lendez
- Laboratorio de Virología, Departamento SAMP, Centro de Investigación Veterinaria de Tandil-CIVETAN (CONICET/UNCPBA/CICPBA), Buenos Aires, Argentina
| | - Guillermina Dolcini
- Laboratorio de Virología, Departamento SAMP, Centro de Investigación Veterinaria de Tandil-CIVETAN (CONICET/UNCPBA/CICPBA), Buenos Aires, Argentina
| | | | - Antônio Fonseca
- Laboratório Federal de Defesa Agropecuária de Minas Gerais, Pedro Leopoldo, Brazil
| | - Subarna Barua
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, 36849-5519, USA
| | - Chengming Wang
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, 36849-5519, USA
| | - Aleksandra Giza
- Department of Omics Analyses, National Veterinary Research Institute, 24-100, Puławy, Poland
| | - Jacek Kuźmak
- Department of Biochemistry, National Veterinary Research Institute, Puławy, 24-100, Poland
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Watanuki S, Shoji K, Izawa M, Okami M, Ye Y, Bao A, Liu Y, Saitou E, Sugiyama K, Endo M, Matsumoto Y, Aida Y. Development of Dry and Liquid Duplex Reagent Mix-Based Polymerase Chain Reaction Assays as Novel Tools for the Rapid and Easy Quantification of Bovine Leukemia Virus (BLV) Proviral Loads. Viruses 2024; 16:1016. [PMID: 39066179 PMCID: PMC11281531 DOI: 10.3390/v16071016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/10/2024] [Accepted: 06/14/2024] [Indexed: 07/28/2024] Open
Abstract
Bovine leukemia virus (BLV) is prevalent worldwide, causing serious problems in the cattle industry. The BLV proviral load (PVL) is a useful index for estimating disease progression and transmission risk. We previously developed a quantitative real-time PCR (qPCR) assay to measure the PVL using the coordination of common motif (CoCoMo) degenerate primers. Here, we constructed a novel duplex BLV-CoCoMo qPCR assay that can amplify two genes simultaneously using a FAM-labeled MGB probe for the BLV LTR gene and a VIC-labeled MGB probe for the BoLA-DRA gene. This liquid duplex assay maintained its original sensitivity and reproducibility in field samples. Furthermore, we developed a dry duplex assay composed of PCR reagents necessary for the optimized liquid duplex assay. We observed a strong positive correlation between the PVLs measured using the dry and liquid duplex assays. Validation analyses showed that the sensitivity of the dry duplex assay was slightly lower than that of the other methods for the detection of a BLV molecular clone, but it showed similar sensitivity to the singleplex assay and slightly higher sensitivity than the liquid duplex assay for the PVL quantification of 82 field samples. Thus, our liquid and dry duplex assays are useful for measuring the BLV PVL in field samples, similar to the original singleplex assay.
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Affiliation(s)
- Sonoko Watanuki
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
| | - Kazuyuki Shoji
- Molecular Diagnosis Division, Nippon Gene Co., Ltd., 2-8-16 Toiya-machi, Toyama 930-0834, Japan
| | - Masaki Izawa
- Molecular Diagnosis Division, Nippon Gene Co., Ltd., 2-8-16 Toiya-machi, Toyama 930-0834, Japan
| | - Mitsuaki Okami
- Molecular Diagnosis Division, Nippon Gene Co., Ltd., 2-8-16 Toiya-machi, Toyama 930-0834, Japan
| | - Yingbao Ye
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
| | - Aronggaowa Bao
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
| | - Yulin Liu
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
| | - Etsuko Saitou
- Hyogo Prefectural Awaji Meat Inspection Center, 49-18 Shitoorinagata, Minamiawaji 656-0152, Japan
| | | | - Michiru Endo
- Kumagaya Livestock Hygiene Service Center, Kumagaya 360-0813, Japan
| | - Yasunobu Matsumoto
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
- Laboratory of Global Animal Resource Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yoko Aida
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan; (S.W.)
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Davies H, Dastjerdi A, Everest D, Floyd T, Collins R, McFadzean H, Reuter G, Reichel R. Incidental finding of a human-like tusavirus in a lamb with lip lesions and fatal pneumonia. J Gen Virol 2024; 105:001968. [PMID: 38441565 PMCID: PMC10999738 DOI: 10.1099/jgv.0.001968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/27/2024] [Indexed: 03/07/2024] Open
Abstract
Tusaviruses in the genus Protoparvovirus of family Parvoviridae were first identified in a diarrhoeic Tunisian child in 2014. Thereafter, high prevalence of a genetically similar virus was demonstrated in faeces from caprine and ovine species in Hungary. Here, we describe an investigation into the cause of scabby lip lesions in a 6 month-old lamb, submitted from a farm experiencing weight loss and scouring in lambs in England. Transmission electron microscopy visualised small circular particles of 18 and 22 nm in diameter in lip lesions identified as tusavirus and flumine parvovirus by Next Generation Sequencing. Liver, kidney, lung, small intestine content and faeces were also strongly positive for the tusavirus DNA as well as 10 % of faecal samples of the flock collected 2 months after the initial lip sampling. NS1 and VP1 amino acid sequences of this tusavirus displayed 99.5 and 92.89 % identity to those of a human tusavirus, respectively. These amino acid identities were at 95.5 and 89.68 % when compared to those of a goat tusavirus. Phylogenetic analysis of the NS1 and VP1 also grouped the virus in the genus Protoparvovirus and close to tusaviruses detected in human, ovine and caprine species. Wider surveillance of the virus indicated a broader geographical distribution for the virus in England. Histology of the lip tissue revealed localised areas of epidermal hyperplasia and hyperkeratosis affecting haired skin, with mild leucocyte infiltration of the subjacent dermis, but no changes to implicate virus involvement. Flumine parvovirus was concluded to be an environment contaminant. Broader studies in prevalence of these virus in UK sheep flocks and human population, animal models and experimental infections could provide insights into the pathogenesis of these novel viruses and their zoonotic potential.
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Affiliation(s)
- Hannah Davies
- Animal and Plant Health Agency (APHA)- Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - Akbar Dastjerdi
- Animal and Plant Health Agency (APHA)- Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - David Everest
- Animal and Plant Health Agency (APHA)- Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - Tobias Floyd
- Animal and Plant Health Agency (APHA)- Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - Rachael Collins
- APHA-Starcross, Staplake mount, Starcross, Exeter, Devon, EX6 8PE, UK
| | - Harriet McFadzean
- APHA-Starcross, Staplake mount, Starcross, Exeter, Devon, EX6 8PE, UK
| | - Gábor Reuter
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Pécs, Hungary
| | - Rudolf Reichel
- APHA-Thirsk, Wests House, Station Road, Thirsk North, Yorkshire, YO7 1PZ, UK
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Lv G, Wang J, Lian S, Wang H, Wu R. The Global Epidemiology of Bovine Leukemia Virus: Current Trends and Future Implications. Animals (Basel) 2024; 14:297. [PMID: 38254466 PMCID: PMC10812804 DOI: 10.3390/ani14020297] [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: 12/08/2023] [Revised: 01/02/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Bovine leukemia virus (BLV) is a retrovirus that causes enzootic bovine leucosis (EBL), which is the most significant neoplastic disease in cattle. Although EBL has been successfully eradicated in most European countries, infections continue to rise in Argentina, Brazil, Canada, Japan, and the United States. BLV imposes a substantial economic burden on the cattle industry, particularly in dairy farming, as it leads to a decline in animal production performance and increases the risk of disease. Moreover, trade restrictions on diseased animals and products between countries and regions further exacerbate the problem. Recent studies have also identified fragments of BLV nucleic acid in human breast cancer tissues, raising concerns for public health. Due to the absence of an effective vaccine, controlling the disease is challenging. Therefore, it is crucial to accurately detect and diagnose BLV at an early stage to control its spread and minimize economic losses. This review provides a comprehensive examination of BLV, encompassing its genomic structure, epidemiology, modes of transmission, clinical symptoms, detection methods, hazards, and control strategies. The aim is to provide strategic information for future BLV research.
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Affiliation(s)
- Guanxin Lv
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (G.L.); (J.W.); (S.L.)
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, Daqing 163319, China
- China Key Laboratory of Bovine Disease Control in Northeast China, Ministry of Agriculture and Rural Affairs, Daqing 163319, China
| | - Jianfa Wang
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (G.L.); (J.W.); (S.L.)
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, Daqing 163319, China
- China Key Laboratory of Bovine Disease Control in Northeast China, Ministry of Agriculture and Rural Affairs, Daqing 163319, China
| | - Shuai Lian
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (G.L.); (J.W.); (S.L.)
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, Daqing 163319, China
- China Key Laboratory of Bovine Disease Control in Northeast China, Ministry of Agriculture and Rural Affairs, Daqing 163319, China
| | - Hai Wang
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (G.L.); (J.W.); (S.L.)
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, Daqing 163319, China
- China Key Laboratory of Bovine Disease Control in Northeast China, Ministry of Agriculture and Rural Affairs, Daqing 163319, China
| | - Rui Wu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (G.L.); (J.W.); (S.L.)
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, Daqing 163319, China
- China Key Laboratory of Bovine Disease Control in Northeast China, Ministry of Agriculture and Rural Affairs, Daqing 163319, China
- College of Biology and Agriculture, Jiamusi University, Jiamusi 154007, China
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Suárez Archilla G, Gutiérrez G, Camussone C, Calvinho L, Abdala A, Alvarez I, Petersen M, Franco L, Destefano G, Monti G, Jacques JR, Joris T, Willems L, Trono K. A safe and effective vaccine against bovine leukemia virus. Front Immunol 2022; 13:980514. [PMID: 36032174 PMCID: PMC9399851 DOI: 10.3389/fimmu.2022.980514] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 07/20/2022] [Indexed: 11/21/2022] Open
Abstract
Previous attempts to develop a vaccine against bovine leukemia virus (BLV) have not been successful because of inadequate or short-lived stimulation of all immunity components. In this study, we designed an approach based on an attenuated BLV provirus by deleting genes dispensable for infectivity but required for efficient replication. The ability of the vaccine to protect from natural BLV infection was investigated in the context of dairy productive conditions in an endemic region. The attenuated vaccine was tested in a farm in which the prevalence rose from 16.7% in young cattle at the beginning of the study to more than 90% in adult individuals. Sterilizing immunity was obtained in 28 out of 29 vaccinated heifers over a period of 48 months, demonstrating the effectiveness of the vaccine. As indicated by the antiviral antibody titers, the humoral response was slightly reduced compared to wild-type infection. After initial post-vaccination bursts, the proviral loads of the attenuated vaccine remained most frequently undetectable. During the first dairy cycle, proviral DNA was not detected by nested-PCR in milk samples from vaccinated cows. During the second dairy cycle, provirus was sporadically detected in milk of two vaccinated cows. Forty-two calves born from vaccinated cows were negative for proviral DNA but had antiviral antibodies in their peripheral blood. The attenuated strain was not transmitted to sentinels, further supporting the safety of the vaccine. Altogether, these data thus demonstrate that the vaccine against BLV is safe and effective in herd conditions characterized by a very high incidence. This cost-effective approach will thus decrease the prevalence of BLV without modification of production practices. After facing a series of challenges pertaining to effectiveness and biosafety, the vaccine is now available for further large-scale delivery. The different challenges and hurdles that were bypassed may be informative for the development of a vaccine against HTLV-1.
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Affiliation(s)
- Guillermo Suárez Archilla
- Instituto de Investigación de la Cadena Láctea (INTA-CONICET), Estación Experimental Agropecuaria Rafaela, Rafaela, Argentina
| | - Gerónimo Gutiérrez
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
| | - Cecilia Camussone
- Instituto de Investigación de la Cadena Láctea (INTA-CONICET), Estación Experimental Agropecuaria Rafaela, Rafaela, Argentina
| | - Luis Calvinho
- Instituto de Investigación de la Cadena Láctea (INTA-CONICET), Estación Experimental Agropecuaria Rafaela, Rafaela, Argentina
| | - Alejandro Abdala
- Instituto de Investigación de la Cadena Láctea (INTA-CONICET), Estación Experimental Agropecuaria Rafaela, Rafaela, Argentina
| | - Irene Alvarez
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
| | - Marcos Petersen
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
| | - Lautaro Franco
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
| | - Gabriel Destefano
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
| | - Gustavo Monti
- Quantitative Veterinary Epidemiology Group, Wageningen University and Research, Wageningen, Netherlands
| | - Jean-Rock Jacques
- Molecular and Cellular Epigenetics (GIGA) and Molecular Biology (TERRA), University of Liège (ULiège), Liège, Belgium
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) of University of Liège (ULiège), Liège, Belgium
| | - Thomas Joris
- Molecular and Cellular Epigenetics (GIGA) and Molecular Biology (TERRA), University of Liège (ULiège), Liège, Belgium
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) of University of Liège (ULiège), Liège, Belgium
| | - Luc Willems
- Molecular and Cellular Epigenetics (GIGA) and Molecular Biology (TERRA), University of Liège (ULiège), Liège, Belgium
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) of University of Liège (ULiège), Liège, Belgium
- *Correspondence: Luc Willems,
| | - Karina Trono
- Instituto de Virología e Innovaciones Tecnológicas, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, (INTA-CONICET), Hurlingham, Argentina
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De Brun ML, Cosme B, Petersen M, Alvarez I, Folgueras-Flatschart A, Flatschart R, Panei CJ, Puentes R. Development of a droplet digital PCR assay for quantification of the proviral load of bovine leukemia virus. J Vet Diagn Invest 2022; 34:439-447. [PMID: 35369822 PMCID: PMC9254064 DOI: 10.1177/10406387221085581] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Droplet digital PCR (ddPCR) is a highly sensitive tool developed for the detection and quantification of short-sequence variants—a tool that offers unparalleled precision enabling measurement of smaller-fold changes. We describe here the use of ddPCR for the detection of Bovine leukemia virus (BLV) DNA provirus. Serum samples and whole blood from experimentally infected sheep and naturally infected cattle were analyzed through ddPCR to detect the BLV gp51 gene, and then compared with serologic and molecular tests. The ddPCR assay was significantly more accurate and sensitive than AGID, ELISA, nested PCR, and quantitative PCR. The limit of detection of ddPCR was 3.3 copies/µL, detecting positive experimentally infected sheep beginning at 6 d post-infection. The ddPCR methodology offers a promising tool for evaluating the BLV proviral load, particularly for the detection of low viral loads.
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Affiliation(s)
- María L. De Brun
- Instituto de Patobiología, Unidad de Microbiología, Facultad de Veterinaria–Universidad de la República, Montevideo, Uruguay
| | - Bruno Cosme
- Instituto Nacional de Metrología, Calidad y Tecnología (Inmetro), Rio de Janeiro, Brazil
| | - Marcos Petersen
- Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Virología e Innovaciones Tecnológicas (IVIT), Buenos Aires, Argentina
| | - Irene Alvarez
- Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Virología e Innovaciones Tecnológicas (IVIT), Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | | | - Roberto Flatschart
- Instituto Nacional de Metrología, Calidad y Tecnología (Inmetro), Rio de Janeiro, Brazil
| | - Carlos Javier Panei
- Laboratorio de Virología, Facultad de Ciencias Veterinarias, Universidad Nacional de la Plata (FCV-UNLP), La Plata, Argentina
| | - Rodrigo Puentes
- Instituto de Patobiología, Unidad de Microbiología, Facultad de Veterinaria–Universidad de la República, Montevideo, Uruguay
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7
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Ruggiero VJ, Benitez OJ, Tsai YL, Lee PYA, Tsai CF, Lin YC, Chang HFG, Wang HTT, Bartlett P. On-site detection of bovine leukemia virus by a field-deployable automatic nucleic extraction plus insulated isothermal polymerase chain reaction system. J Virol Methods 2018; 259:116-121. [DOI: 10.1016/j.jviromet.2018.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 05/08/2018] [Accepted: 06/10/2018] [Indexed: 12/12/2022]
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8
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Petersen M, Alvarez I, Trono K, Jaworski J. Quantification of bovine leukemia virus proviral DNA using a low-cost real-time polymerase chain reaction. J Dairy Sci 2018; 101:6366-6374. [DOI: 10.3168/jds.2017-14253] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/01/2018] [Indexed: 11/19/2022]
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9
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Interlaboratory Comparison of Six Real-Time PCR Assays for Detection of Bovine Leukemia Virus Proviral DNA. J Clin Microbiol 2018; 56:JCM.00304-18. [PMID: 29669790 DOI: 10.1128/jcm.00304-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 04/13/2018] [Indexed: 01/09/2023] Open
Abstract
Quantitative real-time PCR (qPCR) is increasingly being used for the detection of bovine leukemia virus (BLV) proviral DNA. Nevertheless, quality control for the validation and standardization of such tests is currently lacking. Therefore, the present study was initiated by three Office International des Epizooties (OIE) reference laboratories and three collaborating laboratories to measure the interlaboratory variability of six already developed and available BLV qPCR assays. For that purpose, an international panel of 58 DNA samples reflecting the dynamic range of the majority of the assays was distributed to six testing centers. Based on qualitative results, the overall agreement among all six laboratories was moderate. However, significant variability in the measurement of the BLV proviral DNA copy number was observed among different laboratories. Quantitative PCR assays, even when performed by experienced staff, can yield large variability in BLV proviral DNA copy numbers without harmonization. Further standardization of different factors (i.e., utilization of unified protocols and unique calibrators) should increase interlaboratory agreement.
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Carignano HA, Beribe MJ, Caffaro ME, Amadio A, Nani JP, Gutierrez G, Alvarez I, Trono K, Miretti MM, Poli MA. BOLA-DRB3gene polymorphisms influence bovine leukaemia virus infection levels in Holstein and Holstein × Jersey crossbreed dairy cattle. Anim Genet 2017; 48:420-430. [DOI: 10.1111/age.12566] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2017] [Indexed: 12/11/2022]
Affiliation(s)
- H. A. Carignano
- Instituto de Genética; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
| | - M. J. Beribe
- Estación Experimental Agropecuaria Pergamino - INTA; Pergamino B2700 Argentina
| | - M. E. Caffaro
- Instituto de Genética; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
| | - A. Amadio
- Estación Experimental Agropecuaria Rafaela - INTA; Rafaela S2300 Santa Fe Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Ciudad Autónoma de Buenos Aires C1033AAJ Argentina
| | - J. P. Nani
- Estación Experimental Agropecuaria Rafaela - INTA; Rafaela S2300 Santa Fe Argentina
| | - G. Gutierrez
- Instituto de Virología; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
| | - I. Alvarez
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Ciudad Autónoma de Buenos Aires C1033AAJ Argentina
- Instituto de Virología; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
| | - K. Trono
- Instituto de Virología; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
| | - M. M. Miretti
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Ciudad Autónoma de Buenos Aires C1033AAJ Argentina
- Grupo de Investigación en Genética Aplicada; Instituto de Biología Subtropical (GIGA - IBS); Universidad Nacional de Misiones; Posadas N3300 Argentina
| | - M. A. Poli
- Instituto de Genética; Centro de Investigaciones en Ciencias Veterinarias y Agronómicas - INTA; Hurlingham B1686 Argentina
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A quantitative RT-PCR assay for rapid detection of Eurasian-lineage H10 subtype influenza A virus. Virol Sin 2017; 31:444-447. [PMID: 27699612 DOI: 10.1007/s12250-016-3826-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Yuan Y, Kitamura-Muramatsu Y, Saito S, Ishizaki H, Nakano M, Haga S, Matoba K, Ohno A, Murakami H, Takeshima SN, Aida Y. Detection of the BLV provirus from nasal secretion and saliva samples using BLV-CoCoMo-qPCR-2: Comparison with blood samples from the same cattle. Virus Res 2015; 210:248-54. [PMID: 26298004 DOI: 10.1016/j.virusres.2015.08.013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/12/2015] [Accepted: 08/12/2015] [Indexed: 10/23/2022]
Abstract
Bovine leukemia virus (BLV) induces enzootic bovine leukosis, which is the most common neoplastic disease in cattle. Sero-epidemiological studies show that BLV infection occurs worldwide. Direct contact between infected and uninfected cattle is thought to be one of the risk factors for BLV transmission. Contact transmission occurs via a mixture of natural sources, blood, and exudates. To confirm that BLV provirus is detectable in these samples, matched blood, nasal secretion, and saliva samples were collected from 50 cattle, and genomic DNA was extracted. BLV-CoCoMo-qPCR-2, an assay developed for the highly sensitive detection of BLV, was then used to measure the proviral load in blood (n=50), nasal secretions (n=48), and saliva (n=47) samples. The results showed that 35 blood samples, 14 nasal secretion samples, and 6 saliva samples were positive for the BLV provirus. Matched blood samples from cattle that were positive for the BLV provirus (either in nasal secretion or saliva samples) were also positive in their blood. The proviral load in the positive blood samples was >14,000 (copies/1×10(5) cells). Thus, even though the proviral load in the nasal secretion and saliva samples was much lower (<380 copies/1×10(5) cells) than that in the peripheral blood, prolonged direct contact between infected and healthy cattle may be considered as a risk factor for BLV transmission.
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Affiliation(s)
- Yuan Yuan
- RIKEN GENESIS CO., LTD., RIKEN Yokohama Institute, East Research Building 3F, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Yuri Kitamura-Muramatsu
- RIKEN GENESIS CO., LTD., RIKEN Yokohama Institute, East Research Building 3F, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Susumu Saito
- RIKEN GENESIS CO., LTD., RIKEN Yokohama Institute, East Research Building 3F, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.
| | - Hiroshi Ishizaki
- NARO Institute of Livestock and Grassland Science, 768 Senbonmatsu, Nasushiobara, Tochigi 329-2793, Japan
| | - Miwa Nakano
- NARO Institute of Livestock and Grassland Science, 768 Senbonmatsu, Nasushiobara, Tochigi 329-2793, Japan
| | - Satoshi Haga
- NARO Institute of Livestock and Grassland Science, 768 Senbonmatsu, Nasushiobara, Tochigi 329-2793, Japan
| | - Kazuhiro Matoba
- NARO Institute of Livestock and Grassland Science, 768 Senbonmatsu, Nasushiobara, Tochigi 329-2793, Japan
| | - Ayumu Ohno
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hironobu Murakami
- School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan
| | | | - Yoko Aida
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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Gutiérrez G, Lomonaco M, Alvarez I, Fernandez F, Trono K. Characterization of colostrum from dams of BLV endemic dairy herds. Vet Microbiol 2015; 177:366-9. [DOI: 10.1016/j.vetmic.2015.03.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 02/27/2015] [Accepted: 03/02/2015] [Indexed: 11/28/2022]
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Polat M, Ohno A, Takeshima SN, Kim J, Kikuya M, Matsumoto Y, Mingala CN, Onuma M, Aida Y. Detection and molecular characterization of bovine leukemia virus in Philippine cattle. Arch Virol 2014; 160:285-96. [PMID: 25399399 DOI: 10.1007/s00705-014-2280-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 10/31/2014] [Indexed: 02/03/2023]
Abstract
Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis, which is the most common neoplastic disease of cattle. BLV infects cattle worldwide, imposing a severe economic impact on the dairy cattle industry. However, there are no comprehensive studies on the distribution of BLV in the Philippines, and the genetic characteristics of Philippine BLV strains are unknown. Therefore, the aim of this study was to detect BLV infections in the Philippines and determined their genetic variability. Blood samples were obtained from 1116 cattle from different farms on five Philippine islands, and BLV provirus was detected by BLV-CoCoMo-qPCR-2 and nested PCR targeting BLV long terminal repeats. Out of 1116 samples, 108 (9.7 %) and 54 (4.8 %) were positive for BLV provirus, as determined by BLV-CoCoMo-qPCR-2 and nested PCR, respectively. Of the five islands, Luzon Island showed the highest prevalence of BLV infection (23.1 %). Partial env gp51 genes from 43 samples, which were positive for BLV provirus by both methods, were sequenced for phylogenetic analysis. Phylogenetic analysis based on a 423-bp fragment of the env gene revealed that Philippine BLV strains clustered into either genotype 1 or genotype 6. Substitutions were mainly found in antigenic determinants, such as the CD4(+) T-cell epitope, the CD8(+) T-cell epitope, the second neutralizing domain, B and E epitopes, and these substitutions varied according to genotype. This study provides comprehensive information regarding BLV infection levels in the Philippines and documents the presence of two BLV genotypes, genotypes 1 and 6, in this population.
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Affiliation(s)
- Meripet Polat
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Saitama, Japan
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Gutiérrez G, Alvarez I, Merlini R, Rondelli F, Trono K. Dynamics of perinatal bovine leukemia virus infection. BMC Vet Res 2014; 10:82. [PMID: 24708791 PMCID: PMC3986441 DOI: 10.1186/1746-6148-10-82] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 03/31/2014] [Indexed: 01/18/2023] Open
Abstract
Background Bovine leukemia virus (BLV) is highly endemic in many countries, including Argentina. As prevention of the spread from infected animals is of primary importance in breaking the cycle of BLV transmission, it is important to know the pathophysiology of BLV infection in young animals, as they are the main source of animal movement. In this work, we determined the proviral load and antibody titers of infected newborn calves from birth to first parturition (36 months). Results All calves under study were born to infected dams with high proviral load (PVL) in blood and high antibody titers and detectable provirus in the colostrum. The PVL for five out of seven calves was low at birth. All animals reached PVLs of more than 1% infected peripheral blood mononuclear cells (PBMCs), three at 3 months, one at 6 months, and one at 12 months. High PVLs persisted until the end of the study, and, in two animals, exceeded one BLV copy per cell. Two other calves maintained a high PVL from birth until the end of the study. Antibody titers were 32 or higher in the first sample from six out of seven calves. These decayed at 3–6 months to 16 or lower, and then increased again after this point. Conclusions Calves infected during the first week of life could play an active role in early propagation of BLV to susceptible animals, since their PVL raised up during the first 12 months and persist as high for years. Early elimination could help to prevent transmission to young susceptible animals and to their own offspring. To our knowledge, this is the first study of the kinetics of BLV proviral load and antibody titers in newborn infected calves.
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Affiliation(s)
- Gerónimo Gutiérrez
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, CC 1712, Castelar, Argentina.
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Alvarez I, Gutiérrez G, Gammella M, Martínez C, Politzki R, González C, Caviglia L, Carignano H, Fondevila N, Poli M, Trono K. Evaluation of total white blood cell count as a marker for proviral load of bovine leukemia virus in dairy cattle from herds with a high seroprevalence of antibodies against bovine leukemia virus. Am J Vet Res 2013; 74:744-9. [PMID: 23627387 DOI: 10.2460/ajvr.74.5.744] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the reference interval for WBC counts in Holstein dairy cows from herds with high seroprevalence for anti-bovine leukemia virus (BLV) antibodies, analyze the correlation of total WBC counts and blood proviral load (bPVL) in BLV-infected animals, and determine whether total WBC count can be used a hematologic marker for in vivo infection. ANIMALS 307 lactating cows from 16 dairy herds with high BLV seroprevalence. PROCEDURES Blood samples were collected for assessment of plasma anti-BLV p24 antibody concentration (all cows), manual determination of WBC count (161 BLV-seronegative cows from 15 herds), and evaluation of bPVL (146 cows from another herd). RESULTS The WBC count reference interval (ie, mean ± 2 SD) for BLV-seronegative dairy cows was 2,153 to 11,493 cells/μL. Of the 146 cows used to analyze the correlation between WBC count and bPVL, 107 (73%) had WBC counts within the reference interval; of those cows, only 21 (19.6%) had high bPVL. Most cows with high WBC counts (35/39) had high bPVL. Mean WBC count for cows with high bPVL was significantly higher than values for cows with low or undetectable bPVL. White blood cell counts and bPVL were significantly (ρ = 0.71) correlated. CONCLUSIONS AND CLINICAL RELEVANCE These data have provided an updated reference interval for WBC counts in Holstein cows from herds with high BLV seroprevalence. In dairy cattle under natural conditions, WBC count was correlated with bPVL; thus, WBC count determination could be a potential tool for monitoring BLV infection levels in attempts to control transmission.
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Affiliation(s)
- Irene Alvarez
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria (INTA), CC 1686, Hurlingham, Buenos Aires, Argentina.
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Panei CJ, Takeshima SN, Omori T, Nunoya T, Davis WC, Ishizaki H, Matoba K, Aida Y. Estimation of bovine leukemia virus (BLV) proviral load harbored by lymphocyte subpopulations in BLV-infected cattle at the subclinical stage of enzootic bovine leucosis using BLV-CoCoMo-qPCR. BMC Vet Res 2013; 9:95. [PMID: 23641811 PMCID: PMC3648496 DOI: 10.1186/1746-6148-9-95] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 04/17/2013] [Indexed: 11/20/2022] Open
Abstract
Background Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis (EBL), which is the most common neoplastic disease of cattle. BLV infection may remain clinically silent at the aleukemic (AL) stage, cause persistent lymphocytosis (PL), or, more rarely, B cell lymphoma. BLV has been identified in B cells, CD2+ T cells, CD3+ T cells, CD4+ T cells, CD8+ T cells, γ/δ T cells, monocytes, and granulocytes in infected cattle that do not have tumors, although the most consistently infected cell is the CD5+ B cell. The mechanism by which BLV causes uncontrolled CD5+ B cell proliferation is unknown. Recently, we developed a new quantitative real-time polymerase chain reaction (PCR) method, BLV-CoCoMo-qPCR, which enabled us to demonstrate that the proviral load correlates not only with BLV infection, as assessed by syncytium formation, but also with BLV disease progression. The present study reports the distribution of BLV provirus in peripheral blood mononuclear cell subpopulations isolated from BLV-infected cows at the subclinical stage of EBL as examined by cell sorting and BLV-CoCoMo-qPCR. Results Phenotypic characterization of five BLV-infected but clinically normal cattle with a proviral load of > 100 copies per 1 × 105 cells identified a high percentage of CD5+ IgM+ cells (but not CD5- IgM+ B cells, CD4+ T cells, or CD8+T cells). These lymphocyte subpopulations were purified from three out of five cattle by cell sorting or using magnetic beads, and the BLV proviral load was estimated using BLV-CoCoMo-qPCR. The CD5+ IgM+ B cell population in all animals harbored a higher BLV proviral load than the other cell populations. The copy number of proviruses infecting CD5- IgM+ B cells, CD4+ cells, and CD8+ T cells (per 1 ml of blood) was 1/34 to 1/4, 1/22 to 1/3, and 1/31 to 1/3, respectively, compared with that in CD5+ IgM+ B cells. Moreover, the BLV provirus remained integrated into the genomic DNA of CD5+ IgM+ B cells, CD5- IgM+ B cells, CD4+ T cells, and CD8+ T cells, even in BLV-infected cattle with a proviral load of <100 copies per 105 cells. Conclusions The results of the recent study showed that, although CD5+ IgM+ B cells were the main cell type targeted in BLV-infected but clinically normal cattle, CD5- IgM+ B cells, CD4+ cells, and CD8+ T cells were infected to a greater extent than previously thought.
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Rola-Łuszczak M, Finnegan C, Olech M, Choudhury B, Kuźmak J. Development of an improved real time PCR for the detection of bovine leukaemia provirus nucleic acid and its use in the clarification of inconclusive serological test results. J Virol Methods 2013; 189:258-64. [PMID: 23499259 DOI: 10.1016/j.jviromet.2013.02.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 02/21/2013] [Accepted: 02/27/2013] [Indexed: 10/27/2022]
Abstract
With the aim to erradicate Enzootic Bovine Leukosis from Poland, a more sensitive real-time polymerase chain reaction was required and developed to detect proviral Bovine leukaemia virus (BLV) DNA, the causative agent of Enzootic Bovine Leukosis (EBL). This new method proved more sensitive for our needs, than the current protocols available in the public domain. DNA was extracted from peripheral blood leukocytes of 51 cattle, which had given rise to doubtful serological test results by ELISA, and from mesenteric lymph nodes of six cattle that were slaughtered as EBL suspect cases. Additionally, fourteen DNA samples were obtained from animals with a strong BLV antibody response by ELISA. All real-time data were compared to results obtained from three different nested PCR methods. All 14 strongly positive ELISA samples were positive in all PCR tests. The real-time assay in comparison to the conventional PCR methods detected 7.8% (4/51) more specimens positive for BLV nucleic acid and showed a detection limit down to one copy. These observations represent the first report in the value of using a real-time method to help elucidate the disease status of animals when inconclusive ELISA results are obtained in the diagnostic laboratory. Thus, this method should be recommended for use in countries which have implemented an EBL-eradication programme, where a low level of BLV infection is evident.
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Affiliation(s)
- Marzena Rola-Łuszczak
- OIE Reference Laboratory for EBL, Department of Biochemistry, National Veterinary Research Institute, Pulawy, Poland.
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Li Z, Cui L, Zhou M, Qi X, Bao C, Hu J, Shan J, Wu B, Wang S, Guo X, Jiao Y, Tang F, Wang H. Development and application of a one-step real-time RT-PCR using a minor-groove-binding probe for the detection of a novel bunyavirus in clinical specimens. J Med Virol 2012; 85:370-7. [DOI: 10.1002/jmv.23415] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2012] [Indexed: 11/06/2022]
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Gutiérrez G, Carignano H, Alvarez I, Martínez C, Porta N, Politzki R, Gammella M, Lomonaco M, Fondevila N, Poli M, Trono K. Bovine leukemia virus p24 antibodies reflect blood proviral load. BMC Vet Res 2012; 8:187. [PMID: 23047073 PMCID: PMC3526540 DOI: 10.1186/1746-6148-8-187] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 10/04/2012] [Indexed: 11/24/2022] Open
Abstract
Background Bovine leukemia virus (BLV) is worldwide distributed and highly endemic in Argentina. Among the strategies to prevent BLV dissemination, a control plan based on the selective segregation of animals according to their proviral load (PVL) is promising for our dairy productive system. The objective of this work was to study the relationship between the blood PVL and the antibody level, in order to identify whether the individual humoral response, i.e. the anti-p24 or anti-whole-BLV particle, could be used as a marker of the blood level of infection and thus help to recruit animals that may pose a lower risk of dissemination under natural conditions. Results The prevalence of p24 antibodies on the 15 farms studied was over 66%. The prevalence of p24 and whole-BLV antibodies and PVL quantification were analyzed in all the samples (n = 196) taken from herds T1 and 51. ROC analysis showed a higher AUC for p24 antibodies than whole-BLV antibodies (Zreactivity: 3.55, P < 0.001; Ztiter: 2.88, P < 0.01), and as consequence a better performance to predict the proviral load status in herd 51. No significant differences were found between the performance of p24 and whole-BLV antibodies in herd T1. A significant positive correlation was observed between PVL values and p24 antibody reactivity in both farms (r T1 = 0.7, P < 0.001, r 51 = 0.71, P < 0.0001). The analysis was extended to the whole number of weak p24 antibody reactors (n = 311) of the other 13 farms. The mean of high PVL reactors within weak p24 reactors was 17.38% (SD = 8.92). In 5/15 farms, the number of weak p24 reactors with high PVL was lower than 10%. Conclusions We found that the humoral response reflected the level of in vivo infection, and may therefore have useful epidemiological applications. Whereas the quantitative evaluation of blood proviral load using real-time PCR is expensive and technically demanding, the measurement of antibodies in blood by ELISA is relatively straightforward and could therefore constitute a cost-effective tool in a BLV control intervention strategy, especially in highly infected herds such as Argentinean dairy ones.
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Affiliation(s)
- Gerónimo Gutiérrez
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, C.C. 1712, Castelar, Argentina.
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Jimba M, Takeshima SN, Murakami H, Kohara J, Kobayashi N, Matsuhashi T, Ohmori T, Nunoya T, Aida Y. BLV-CoCoMo-qPCR: a useful tool for evaluating bovine leukemia virus infection status. BMC Vet Res 2012; 8:167. [PMID: 22995575 PMCID: PMC3489618 DOI: 10.1186/1746-6148-8-167] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 09/13/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis, which is the most common neoplastic disease of cattle. BLV infects cattle worldwide, imposing a severe economic impact on the dairy cattle industry. Recently, we developed a new quantitative real-time polymerase chain reaction (PCR) method using Coordination of Common Motifs (CoCoMo) primers to measure the proviral load of known and novel BLV variants in BLV-infected animals. Indeed, the assay was highly effective in detecting BLV in cattle from a range of international locations. This assay enabled us to demonstrate that proviral load correlates not only with BLV infection capacity as assessed by syncytium formation, but also with BLV disease progression. In this study, we compared the sensitivity of our BLV-CoCoMo-qPCR method for detecting BLV proviruses with the sensitivities of two real-time PCR systems, and also determined the differences of proviral load with serotests. RESULTS BLV-CoCoMo-qPCR was found to be highly sensitive when compared with the real-time PCR-based TaqMan MGB assay developed by Lew et al. and the commercial TaKaRa cycleave PCR system. The BLV copy number determined by BLV-CoCoMo-qPCR was only partially correlated with the positive rate for anti-BLV antibody as determined by the enzyme-linked immunosorbent assay, passive hemagglutination reaction, or agar gel immunodiffusion. This result indicates that, although serotests are widely used for the diagnosis of BLV infection, it is difficult to detect BLV infection with confidence by using serological tests alone. Two cattle were experimentally infected with BLV. The kinetics of the provirus did not precisely correlate with the change in anti-BLV antibody production. Moreover, both reactions were different in cattle that carried different bovine leukocyte antigen (BoLA)-DRB3 genotypes. CONCLUSIONS Our results suggest that the quantitative measurement of proviral load by BLV-CoCoMo-qPCR is useful tool for evaluating the progression of BLV-induced disease. BLV-CoCoMo-qPCR allows us to monitor the spread of BLV infection in different viewpoint compared with classical serotest.
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Affiliation(s)
- Mayuko Jimba
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Yun T, Ni Z, Hua J, Ye W, Chen L, Zhang S, Zhang Y, Zhang C. Development of a one-step real-time RT-PCR assay using a minor-groove-binding probe for the detection of duck Tembusu virus. J Virol Methods 2012; 181:148-54. [DOI: 10.1016/j.jviromet.2012.01.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 01/16/2012] [Accepted: 01/24/2012] [Indexed: 11/15/2022]
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Natural progression of Bovine Leukemia Virus infection in Argentinean dairy cattle. Vet Microbiol 2011; 151:255-63. [DOI: 10.1016/j.vetmic.2011.03.035] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 03/04/2011] [Accepted: 03/31/2011] [Indexed: 11/22/2022]
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Detection of bovine leukemia virus specific antibodies using recombinant p24-ELISA. Vet Microbiol 2009; 137:224-34. [DOI: 10.1016/j.vetmic.2009.01.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 12/29/2008] [Accepted: 01/12/2009] [Indexed: 11/16/2022]
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Yuan SH, Liang XF, Jia WH, Huang JL, Wei M, Deng L, Liang LZ, Wang XY, Zeng YX. Molecular diagnosis of sentinel lymph node metastases in cervical cancer using squamous cell carcinoma antigen. Clin Cancer Res 2008; 14:5571-8. [PMID: 18765550 DOI: 10.1158/1078-0432.ccr-08-0346] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To clarify the prognostic value of molecular diagnosis of SLN metastases in cervical cancer using SCCA. EXPERIMENTAL DESIGN All SLNs and primary tumors, part of non-SLNs, were harvested from 36 patients with cervical cancer. Expression levels of SCCA, cytokeratin 19 (CK19), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA in 178 samples (29 primary tumors, 5 histologic positive nodes, 60 histologic negative SLNs, 69 non-SLNs, and 15 normal nodes) were assessed by quantitative reverse transcription-PCR assay. The quantitative value of SCCA or CK19 mRNA was described as each value relative to GAPDH mRNA. The cutoff value was set at the upper limit of the quantitative value of nodes from noncancer patients, and those above this value constituted the molecular metastasis group. RESULTS The SCCA mRNA expression values were more than 1 x 10(3) in 28 primary tumors and all histologic positive nodes, and its expression levels in SLNs were higher than in non-SLNs. SLNs from patients with adverse prognostic features had higher SCCA mRNA expression levels. Four histologic negative SLNs were diagnosed molecular metastases based on SCCA mRNA. Two cases with histologically uninvolved pelvic nodes recurred. Survival analysis indicates that molecular lymphatic metastasis based on elevated SCCA mRNA level is the best predictor of recurrence. However, CK19 is not a suitable marker due to its low specificity and relative higher baseline expression in normal nodes. CONCLUSIONS SCCA mRNA levels for molecular diagnosis of SLN metastases in cervical cancer more accurately identifies patients at risk for recurrence than the routine histology does.
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Affiliation(s)
- Song-Hua Yuan
- Department of Gynecology, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China
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Jin L, Feng Y, Parry R, Cui A, Lu Y. Real-time PCR and its application to mumps rapid diagnosis. J Med Virol 2007; 79:1761-7. [PMID: 17854025 DOI: 10.1002/jmv.20880] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A real-time polymerase chain reaction assay was initially developed in China to detect mumps genome. The primers and TaqMan-MGB probe were selected from regions of the hemagglutinin gene of mumps virus. The primers and probe for the real-time PCR were evaluated by both laboratories in China and in the UK using three different pieces of equipment, LightCycler (Roche), MJ DNA Engine Option 2 (BIO-RAD) and TaqMan (ABI Prism) on different samples. The reaction was performed with either a one-step (China) or two-step (UK) process. The sensitivity (10 copies) was estimated using a serial dilution of constructed mumps-plasmid DNA and a linear standard curve was obtained between 10 and 10(7) DNA copies/reaction, which can be used to quantify viral loads. The detection limit on cell culture-grown virus was approximately 2 pfu/ml with a two-step assay on TaqMan, which was equivalent to the sensitivity of the nested PCR routinely used in the UK. The specificity was proved by testing a range of respiratory viruses and several genotypes of mumps strains. The concentration of primers and probe is 22 pmol and 6.25 or 7 pmol respectively for a 25 microl reaction. The assay took 3 hr from viral RNA extraction to complete the detection using any of the three pieces of equipment. Three hundred forty-one (35 in China and 306 in the UK) clinical specimens were tested, the results showing that this real-time PCR assay is suitable for rapid and accurate detection of mumps virus RNA in various types of clinical specimens.
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Affiliation(s)
- L Jin
- Virus Reference Department, Centre for Infections, Health Protection Agency, London, UK.
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Lu YY, Yan JY, Feng Y, Xu CP, Shi W, Mao HY. Rapid detection of H5 avian influenza virus by TaqMan-MGB real-time RT-PCR. Lett Appl Microbiol 2007; 46:20-5. [PMID: 17944840 PMCID: PMC7197896 DOI: 10.1111/j.1472-765x.2007.02253.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aims: Real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) assay based on a TaqMan‐minor groove binder (MGB) probe was developed for the rapid detection of avian influenza virus subtype H5. Methods and Results: Conserved regions in the haemagglutinin genes of avian influenza viruses subtype H5 served as targets for the primers and TaqMan‐MGB probe design. Concentrations of primers and probe were optimized to improve the sensitivity and specificity of the reactions. A plasmid containing the haemagglutinin gene was constructed and in vitro transcribed for a quantitative assay of copy numbers of the target gene. The results revealed that the optimal concentration of primers and probe was 640 and 480 nmol l−1, respectively. The threshold of 100 copies of target molecules could be detected. The linear range for detection was determined as 102 to 108 molecules in reaction. Conclusions: It took less than 3 h to complete the detection from viral RNA extraction, with good sensitivity and repeatability. Significance and Impact of the Study: Real‐time RT‐PCR assay with MGB probe was an effective means for quick and quantitative laboratory detection and monitoring of H5 avian influenza viruses.
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Affiliation(s)
- Y Y Lu
- Institute of Virology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
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29
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Florins A, Gillet N, Boxus M, Kerkhofs P, Kettmann R, Willems L. Even attenuated bovine leukemia virus proviruses can be pathogenic in sheep. J Virol 2007; 81:10195-200. [PMID: 17626096 PMCID: PMC2045414 DOI: 10.1128/jvi.01058-07] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Based on a reverse genetics approach, we previously reported that bovine leukemia virus (BLV) mutants harboring deletions in the accessory R3 and G4 genes persist at very low proviral loads and are unable to induce leukemia or lymphoma in sheep, indicating that these R3 and G4 gene sequences are required for pathogenesis. We now show that lymphoma can occur, albeit infrequently (1 case of 20) and after extended periods of latency (7 years). Direct sequencing and reinfection experiments demonstrated that lymphomagenesis was not due to the reversion of the mutant to the wild type. Similar observations with another type of attenuated mutant impaired in the transmembrane protein (TM) YXXL signaling motifs were made. We conclude that the R3 and G4 genes and the TM YXXL motifs are not strictly required for pathogenesis but that their integrity contributes to disease frequency and latency.
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Affiliation(s)
- Arnaud Florins
- Molecular and Cellular Biology Laboratory, National Fund for Scientific Research-FUSAGx, 13 avenue Maréchal Juin, 5030 Gembloux, Belgium
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30
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McMillen L, Lew AE. Improved detection of Tritrichomonas foetus in bovine diagnostic specimens using a novel probe-based real time PCR assay. Vet Parasitol 2006; 141:204-15. [PMID: 16860481 DOI: 10.1016/j.vetpar.2006.06.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 06/07/2006] [Accepted: 06/16/2006] [Indexed: 10/24/2022]
Abstract
A Tritrichomonas foetus-specific 5' Taq nuclease assay using a 3' minor groove binder-DNA probe (TaqMan MGB) targeting conserved regions of the internal transcribed spacer-1 (ITS-1) was developed and compared to established diagnostic procedures. Specificity of the assay was evaluated using bovine venereal microflora and a range of related trichomonad species. Assay sensitivity was evaluated with log(10) dilutions of known numbers of cells, and compared to that for microscopy following culture (InPouch TF test kit) and the conventional TFR3-TFR4 PCR assay. The 5' Taq nuclease assay detected a single cell per assay from smegma or mucus which was 2500-fold or 250-fold more sensitive than microscopy following selective culture from smegma or mucus respectively, and 500-fold more sensitive than culture followed by conventional PCR assay. The sensitivity of the conventional PCR assay was comparable to the 5' Taq nuclease assay when testing purified DNA extracted from clinical specimens, whereas the 5' Taq nuclease assay sensitivity improved using crude cell lysates, which were not suitable as template for the conventional PCR assay. Urine was evaluated as a diagnostic specimen providing improved and equivalent levels of T. foetus detection in spiked urine by both microscopy following culture and direct 5' Taq nuclease detection, respectively, compared with smegma and mucus, however inconclusive results were obtained with urine samples from the field study. Diagnostic specimens (n=159) were collected from herds with culture positive animals and of the 14 animals positive by 5' Taq nuclease assay, 3 were confirmed by selective culture/microscopy detection (Fisher's exact test P<0.001). The 5' Taq nuclease assay described here demonstrated superior sensitivity to traditional culture/microscopy and offers advantages over the application of conventional PCR for the detection of T. foetus in clinical samples.
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Affiliation(s)
- Lyle McMillen
- Department of Primary Industries and Fisheries, Locked Mail Bag No. 4, Moorooka, 4105 Qld, Australia
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31
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Florins A, Gillet N, Asquith B, Debacq C, Jean G, Schwartz-Cornil I, Bonneau M, Burny A, Reichert M, Kettmann R, Willems L. Spleen-dependent turnover of CD11b peripheral blood B lymphocytes in bovine leukemia virus-infected sheep. J Virol 2006; 80:11998-2008. [PMID: 17035334 PMCID: PMC1676270 DOI: 10.1128/jvi.01447-06] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Lymphocyte homeostasis is determined by a critical balance between cell proliferation and death, an equilibrium which is deregulated in bovine leukemia virus (BLV)-infected sheep. We have previously shown that an excess of proliferation occurs in lymphoid tissues and that the peripheral blood population is prone to increased cell death. To further understand the mechanisms involved, we evaluated the physiological role of the spleen in this accelerated turnover. To this end, B lymphocytes were labeled in vivo using a fluorescent marker (carboxyfluorescein diacetate succinimidyl ester), and the cell kinetic parameters (proliferation and death rates) of animals before and after splenectomy were compared. We show that the enhanced cell death observed in BLV-infected sheep is abrogated after splenectomy, revealing a key role of the spleen in B-lymphocyte dynamics.
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Affiliation(s)
- Arnaud Florins
- National Fund for Scientific Research, Molecular and Cellular Biology Laboratory, 13 avenue Maréchal Juin, 5030 Gembloux, Belgium
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32
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McMillen L, Fordyce G, Doogan VJ, Lew AE. Comparison of culture and a novel 5' Taq nuclease assay for direct detection of Campylobacter fetus subsp. venerealis in clinical specimens from cattle. J Clin Microbiol 2006; 44:938-45. [PMID: 16517880 PMCID: PMC1393111 DOI: 10.1128/jcm.44.3.938-945.2006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
A Campylobacter fetus subsp. venerealis-specific 5' Taq nuclease PCR assay using a 3' minor groove binder-DNA probe (TaqMan MGB) was developed based on a subspecies-specific fragment of unknown identity (S. Hum, K. Quinn, J. Brunner, and S. L. On, Aust. Vet. J. 75:827-831, 1997). The assay specifically detected four C. fetus subsp. venerealis strains with no observed cross-reaction with C. fetus subsp. fetus-related Campylobacter species or other bovine venereal microflora. The 5' Taq nuclease assay detected approximately one single cell compared to 100 and 10 cells in the conventional PCR assay and 2,500 and 25,000 cells from selective culture from inoculated smegma and mucus, respectively. The respective detection limits following the enrichments from smegma and mucus were 5,000 and 50 cells/inoculum for the conventional PCR compared to 500 and 50 cells/inoculum for the 5' Taq nuclease assay. Field sampling confirmed the sensitivity and the specificity of the 5' Taq nuclease assay by detecting an additional 40 bulls that were not detected by culture. Urine-inoculated samples demonstrated comparable detection of C. fetus subsp. venerealis by both culture and the 5' Taq nuclease assay; however, urine was found to be less effective than smegma for bull sampling. Three infected bulls were tested repetitively to compare sampling tools, and the bull rasper proved to be the most suitable, as evidenced by the improved ease of specimen collection and the consistent detection of higher levels of C. fetus subsp. venerealis. The 5' Taq nuclease assay demonstrates a statistically significant association with culture (chi2 = 29.8; P < 0.001) and significant improvements for the detection of C. fetus subsp. venerealis-infected animals from crude clinical extracts following prolonged transport.
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Affiliation(s)
- Lyle McMillen
- Queensland Department of Primary Industries and Fisheries, c/o Animal Research Institute, Locked Mail Bag No. 4, Moorooka, 4105 QLD, Australia.
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Achachi A, Florins A, Gillet N, Debacq C, Urbain P, Foutsop GM, Vandermeers F, Jasik A, Reichert M, Kerkhofs P, Lagneaux L, Burny A, Kettmann R, Willems L. Valproate activates bovine leukemia virus gene expression, triggers apoptosis, and induces leukemia/lymphoma regression in vivo. Proc Natl Acad Sci U S A 2005; 102:10309-14. [PMID: 16006517 PMCID: PMC1177395 DOI: 10.1073/pnas.0504248102] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Leukemogenic viruses like human T-lymphotropic virus and bovine leukemia virus (BLV) presumably persist in the host partly by latent integration of the provirus in a fraction of infected cells, leading to accumulative increase in the outgrowth of transformed cells. Furthermore, viral infection also correlates with a blockade of the apoptotic mechanisms concomitant with an apparent latency of the host cell. Conceptually, induction of viral or cellular gene expression could thus also be used as a therapeutic strategy against retroviral-associated leukemia. Here, we provide evidence that valproate, an inhibitor of deacetylases, activates BLV gene expression in transient transfection experiments and in short-term cultures of primary B-lymphocytes. In vivo, valproate injection into newly BLV-inoculated sheep did not abrogate primary infection. However, valproate treatment, in the absence of any other cytotoxic drug, was efficient for leukemia/lymphoma therapy in the sheep model leading to decreased lymphocyte numbers (respectively from 25.6, 35.7, and 46.5 x 10(3) cells per mm3 to 1.0, 10.6, and 24.3 x 10(3) cells per mm3 in three leukemic sheep) and tumor regression (from >700 cm3 to undetectable). The concept of a therapy that targets the expression of viral and cellular genes might be a promising treatment of adult T cell leukemia or tropical spastic paraparesis/human T-lymphotropic virus-associated myelopathy, diseases for which no satisfactory treatment exists so far.
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Affiliation(s)
- Amine Achachi
- Molecular and Cellular Biology, Gembloux University Faculty of Agronomic Sciences, 5030 Gembloux, Belgium
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Mackay IM, Arden KE, Nitsche A. Real-time Fluorescent PCR Techniques to Study Microbial-Host Interactions. METHODS IN MICROBIOLOGY 2004; 34:255-330. [PMID: 38620210 PMCID: PMC7148886 DOI: 10.1016/s0580-9517(04)34010-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This chapter describes how real-time polymerase chain reaction (PCR) performs and how it may be used to detect microbial pathogens and the relationship they form with their host. Research and diagnostic microbiology laboratories contain a mix of traditional and leading-edge, in-house and commercial assays for the detection of microbes and the effects they impart upon target tissues, organs, and systems. The PCR has undergone significant change over the last decade, to the extent that only a small proportion of scientists have been able or willing to keep abreast of the latest offerings. The chapter reviews these changes. It discusses the second-generation of PCR technology-kinetic or real-time PCR, a tool gaining widespread acceptance in many scientific disciplines but especially in the microbiology laboratory.
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Affiliation(s)
- Ian M Mackay
- Clinical Virology Research Unit, Sir Albert Sakzewski Virus Research Centre, Royal Children's Hospital, Brisbane, Qld, Australia
- Clinical Medical Virology Centre, University of Queensland, Brisbane, Qld, Australia
| | - Katherine E Arden
- Clinical Virology Research Unit, Sir Albert Sakzewski Virus Research Centre, Royal Children's Hospital, Brisbane, Qld, Australia
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Lew AE, Bock RE, Miles J, Cuttell LB, Steer P, Nadin-Davis SA. Sensitive and specific detection of bovine immunodeficiency virus and bovine syncytial virus by 5' Taq nuclease assays with fluorescent 3' minor groove binder-DNA probes. J Virol Methods 2004; 116:1-9. [PMID: 14715301 DOI: 10.1016/j.jviromet.2003.10.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Sensitive assays are required to detect bovine retroviruses in donor cattle used for the in vivo preparation of Australian tick fever vaccines. 5' Taq nuclease assays using 3' minor groove binder DNA probes (TaqMan)MGB) were developed and compared to conventional PCR assays for the sensitive detection of bovine syncytial virus (BSV) and bovine immunodeficiency virus (BIV). Seven beef and dairy herds were screened to evaluate these tests. Comparative sensitivities of PCR tests were determined by testing log(10) dilutions of plasmids with inserts containing corresponding provirus sequences. Published PCR assays targeting BIV env sequences did not adequately amplify Australian BIV sequences. Pol sequences from Australian strains of BIV and BSV were used to design TaqMan MGB assays, which improved sensitivity 10-fold (BIV) and 100-fold (BSV), respectively, over conventional PCR tests. This is the first report of Australian sequences of BIV and BSV and the first 5' Taq nuclease assays described to detect these viruses. These methods could be applied to future studies requiring sensitive detection of these two bovine retroviruses.
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Affiliation(s)
- Ala E Lew
- Agency for Food and Fibre Sciences, Queensland Department of Primary Industries, c/o Locked Mail Bag No. 4, Moorooka, 4105, Qld, Australia.
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