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Furtado Araújo J, Andrioli A, Pinheiro RR, Peixoto RM, de Sousa ALM, de Azevedo DAA, Lima AMC, Nobre JA, Amaral GP, Brandão IS, da Silva Teixeira MF. Detection and isolation of small ruminant lentivirus in the amniotic fluid of goats. Comp Immunol Microbiol Infect Dis 2021; 78:101693. [PMID: 34399377 DOI: 10.1016/j.cimid.2021.101693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 07/14/2021] [Accepted: 07/26/2021] [Indexed: 12/21/2022]
Abstract
The objective of this study was to verify the presence of small ruminant lentivirus in the amniotic fluid of goats using molecular tests and viral isolation by cocultivation in the amniotic fluid of naturally infected goats. The study analyzed eight goats: seven were small ruminant lentivirus-positive and one was negative. The amniotic fluid was collected from each of the eight animals during cesarean section at 147 days of pregnancy. Cocultivation was undertaken using secondary goat nictitating membrane cell cultures obtained by explant from a small ruminant lentivirus-negative calf followed by trypsinization and sub-cultivation of the cells for 63 days. During this period, five supernatant collections were performed for DNA extraction and subsequent nested polymerase chain reaction. DNA was extracted from the amniotic fluid after 3 h of cellular sedimentation, from which a sample of 600 μL was taken from the sediment and another 600 μL sample from the supernatant. After DNA extraction, nested polymerase chain reaction was performed. Of the eight goats, 62.5 % (05/08) were small ruminant lentivirus-positive, with 43.75 % (07/16) of the total samples positive when considering the two repetitions (supernatant and cell sediment). Moreover, positivity was confirmed by small ruminant lentivirus pro-viral DNA amplification in the cell supernatant throughout the cocultivation period. Small ruminant lentivirus were present in the amniotic fluid samples from the naturally infected goats indicating an intrauterine transmission route. Moreover, this biological fluid can be adopted for the diagnosis of these lentiviruse because it is an important risk factor related to intrauterine transmission.
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Affiliation(s)
- Juscilânia Furtado Araújo
- Doctorate Student in the Northeast Network in Biotechnology, State University of Ceará, Fortaleza, Ceará, Brazil.
| | | | | | - Renato Mesquita Peixoto
- Embrapa Goats and Sheep, Sobral, Ceará, Brazil; Scholarship for Regional Scientific Development of the National Council for Scientific and Technological Development (DCR-CNPq/FUNCAP), Level C, Brasilia, Distrito Federal, Brazil
| | | | | | - Ana Milena Cesar Lima
- Doctorate Student in Animal Science, Federal University of Piauí, Teresina, Piauí, Brazil
| | - Juliana Araújo Nobre
- Master Degree Student Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Gabriel Paula Amaral
- Undergraduate Student in Zootechnics, State University of Acaraú Valley, Sobral, Ceará, Brazil
| | - Iane Sousa Brandão
- Undergraduate Student in Biological Sciences, State University of Acaraú Valley, Sobral, Ceará, Brazil
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van der Kuyl AC, Berkhout B. Viruses in the reproductive tract: On their way to the germ line? Virus Res 2020; 286:198101. [PMID: 32710926 DOI: 10.1016/j.virusres.2020.198101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/17/2020] [Accepted: 07/18/2020] [Indexed: 01/13/2023]
Abstract
Studies of vertebrate genomes have indicated that all species contain in their chromosomes stretches of DNA with sequence similarity to viral genomes. How such 'endogenous' viral elements (EVEs) ended up in host genomes is usually explained in general terms such as 'they entered the germ line at some point during evolution'. This seems a correct statement, but is also rather imprecise. The vast number of endogenous viral sequences suggest that common routes to the 'germ line' may exist, as relying on chance alone may not easily explain the abundance of EVEs in modern mammalian genomes. An increasing number of virus types have been detected in human semen and a growing number of studies have reported on viral infections that cause male infertility or subfertility and on viral infections that threaten in vitro fertilisation practices. Thus, it is timely to survey the pathway(s) that viruses can use to gain access to the human germ line. Embryo transfer and semen quality studies in livestock form another source of relevant information because virus infection during reproduction is clearly unwanted, as is the case for the human situation. In this review, studies on viruses in the male and female reproductive tract and in the early embryo will be discussed to propose a plausible viral route to the mammalian germ line.
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Affiliation(s)
- Antoinette Cornelia van der Kuyl
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers, Amsterdam, The Netherlands.
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers, Amsterdam, The Netherlands
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Pellerin JL, Oseikria M, Moreno D, Rodolakis A, Vorimore F, Laroucau K, Bruyas JF, Roux C, Michaud S, Larrat M, Fieni F. Risk of Chlamydia abortus transmission via embryo transfer using in vitro produced early bovine embryos. Theriogenology 2018; 126:114-120. [PMID: 30551017 DOI: 10.1016/j.theriogenology.2018.11.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 10/27/2022]
Abstract
The objectives of this study were to determine (i) whether Chlamydia (C.) abortus would adhere to the intact zona pellucida (ZP-intact) of early in vitro produced bovine embryos; (ii) whether the bacteria would adhere to the embryos (ZP-free) after in vitro infection; and (iii) the efficacy of the International Embryo Transfer Society (IETS) washing protocol. The experimentation was made twice. For each replicate 100 (8-16-cell) bovine embryos produced in vitro were randomly divided into 10 batches. Height batches (4 ZP-intact and 4 ZP-free) of 10 embryos were incubated in a medium containing 4 × 107Chlamydia/ml of AB7 strain. After incubation for 18 h at 37 °C in an atmosphere of 5% CO2, the embryos were washed in accordance with the IETS guidelines. In parallel, two batches (1 ZP-intact and 1 ZP-free) of 10 embryos were subjected to similar procedures but without exposure to C. abortus as a control group. The 10 washing fluids from each batch were collected and centrifuged for 1 h at 13,000×g. Each batch of washed embryos and each wash pellets were tested using PCR. C. abortus DNA was found in all ZP-intact and ZP-free batches of 10 embryos after 10 successive washes. For ZP-intact infected embryos, Chlamydia-DNA was also detected in all 10 wash baths for two batches (2/8) of embryos, whereas for ZP-free infected embryos, Chlamydia-DNA was detected in all 10 wash baths for 6/8 batches of embryos. In contrast, none of the embryos or their washing fluids in the control batches was DNA positive. The bacterial load for batches of 10 embryos after the 10 wash baths was significantly higher for batches of ZP-free embryos (20.7 ± 9 × 103 bacteria/mL) than for batches of ZP-intact embryos (0.47 ± 0.19 × 103 bacteria/mL). These results demonstrate that C. abortus adheres to the ZP as well as the early embryonic cells of in vitro produced bovine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS fails to remove it.
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Affiliation(s)
- Jean-Louis Pellerin
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Mouhamad Oseikria
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Diego Moreno
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Annie Rodolakis
- INRA, Animal Infectious Diseases and Public Health Tours, France
| | - Fabien Vorimore
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - Karine Laroucau
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - Jean-Fancois Bruyas
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Cécile Roux
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Sandrine Michaud
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Myriam Larrat
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - Francis Fieni
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France.
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Sánchez JH, Martínez HA, García MM, Garrido G, Gómez L, Aguilar JA, de Andrés DF, Reina R, Ramírez H. The presence of small ruminant lentiviruses in Mexican Pelibuey sheep. Theriogenology 2016; 86:1953-1957.e1. [PMID: 27461580 DOI: 10.1016/j.theriogenology.2016.06.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 06/09/2016] [Accepted: 06/15/2016] [Indexed: 02/08/2023]
Abstract
The transmission frequency of small ruminant lentiviruses (SRLVs) through the placenta is controversial and may be associated with breed susceptibility. In Mexico, SRLV infections in sheep have been poorly studied. This work explores the presence of antibodies and proviral DNA in Mexican Pelibuey sheep. Enzyme-linked immunosorbent assays (ELISAs; three commercial kits and two on the basis of synthetic peptides) and polymerase chain reaction (PCR; amplifying the long terminal repeat and gag segments) were performed to diagnose SRLV infection in 25 adult Pelibuey ewes with an average age of 2.5 years and 32 fetuses with gestational ages ranging from 40 to 90 days without clinical signs of SRLV. Two of the three commercial ELISAs and the synthetic peptide-based ones were positive for SRLV antibody detection in 28% and 24% of the ewes, respectively, whereas none of the fetuses were positive by any of the ELISAs. By PCR, 31% of the ewes and, interestingly, two fetuses were positive. Characteristic SRLV lesions were not found in the fetal and/or ewe tissues, including those with positive PCR results. These findings demonstrate the susceptibility of Pelibuey sheep to SRLV infection and the low transmission frequency through the placenta.
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Affiliation(s)
- José H Sánchez
- Laboratorio de Virología, Genética y Biología Molecular, Facultad de Estudios Superiores Cuautitlán (FESC) Campo 4, Universidad Nacional Autónoma de México (UNAM), Estado de México, México
| | - Humberto A Martínez
- Laboratorio de Virología, Genética y Biología Molecular, Facultad de Estudios Superiores Cuautitlán (FESC) Campo 4, Universidad Nacional Autónoma de México (UNAM), Estado de México, México
| | - María M García
- Laboratorio de Inmuno-virología, Unidad de Investigación Médica en Inmunología, UMAE Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Ciudad de México, México
| | - Germán Garrido
- Laboratorio de apoyo a Histología y Biología, FESC, Campo 4, Universidad Nacional Autónoma de México, Estado de México, México
| | - Luis Gómez
- Laboratorio de Virología CENID Microbiología Animal, Instituto Nacional de Investigación Forestal Agrícola y Pecuaria (INIFAP), Ciudad de México, México
| | - José A Aguilar
- Laboratorio de Inmuno-virología, Unidad de Investigación Médica en Inmunología, UMAE Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Ciudad de México, México
| | - Damián F de Andrés
- Instituto de Agrobiotecnología, UPNA-CSIC-Gobierno de Navarra, Navarra, Spain
| | - Ramsés Reina
- Instituto de Agrobiotecnología, UPNA-CSIC-Gobierno de Navarra, Navarra, Spain
| | - Hugo Ramírez
- Laboratorio de Virología, Genética y Biología Molecular, Facultad de Estudios Superiores Cuautitlán (FESC) Campo 4, Universidad Nacional Autónoma de México (UNAM), Estado de México, México.
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Oseikria M, Pellerin JL, Rodolakis A, Vorimore F, Laroucau K, Bruyas JF, Roux C, Michaud S, Larrat M, Fieni F. Can Chlamydia abortus be transmitted by embryo transfer in goats? Theriogenology 2016; 86:1482-1488. [PMID: 27341774 DOI: 10.1016/j.theriogenology.2016.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
Abstract
The objectives of this study were to determine (i) whether Chlamydia abortus would adhere to or penetrate the intact zona pellucida (ZP-intact) of early in vivo-derived caprine embryos, after in vitro infection; and (ii) the efficacy of the International Embryo Transfer Society (IETS) washing protocol for bovine embryos. Fifty-two ZP-intact embryos (8-16 cells), obtained from 14 donors were used in this experiment. The embryos were randomly divided into 12 batches. Nine batches (ZP-intact) of five embryos were incubated in a medium containing 4 × 10(7)Chlamydia/mL of AB7 strain. After incubation for 18 hours at 37 °C in an atmosphere of 5% CO2, the embryos were washed in batches in 10 successive baths of a phosphate buffer saline and 5% fetal calf serum solution in accordance with IETS guidelines. In parallel, three batches of ZP-intact embryos were used as controls by being subjected to similar procedures but without exposure to C. abortus. The 10 wash baths were collected separately and centrifuged for 1 hour at 13,000 × g. The washed embryos and the pellets of the 10 centrifuged wash baths were frozen at -20 °C before examination for evidence of C. abortus using polymerase chain reaction. C. abortus DNA was found in all of the infected batches of ZP-intact embryos (9/9) after 10 successive washes. It was also detected in the 10th wash fluid for seven batches of embryos, whereas for the two other batches, the last positive wash bath was the eighth and the ninth, respectively. In contrast, none of the embryos or their washing fluids in the control batches were DNA positive. These results report that C. abortus adheres to and/or penetrates the ZP of in vivo caprine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS for bovine embryos, failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor goats to healthy recipients and/or their offspring. Nevertheless, the detection of C. abortus DNA by polymerase chain reaction does not prove that the bacteria found was infectious. Further studies are required to investigate whether enzymatic and/or antibiotic treatment of caprine embryos infected by C. abortus would eliminate the bacteria from the ZP.
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Affiliation(s)
- M Oseikria
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - J L Pellerin
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - A Rodolakis
- INRA, Animal Infectious Diseases and Public Health, Tours, France
| | - F Vorimore
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - K Laroucau
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - J F Bruyas
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - C Roux
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - S Michaud
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - M Larrat
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - F Fieni
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France.
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Turchetti AP, Paniago JJ, da Costa LF, da Cruz JC, Braz GF, Gouveia AM, Paixão TA, Santos RL, Heinemann MB. Distribution of caprine arthritis encephalitis virus provirus, RNA, and antigen in the reproductive tract of one naturally and seven experimentally infected bucks. Theriogenology 2013; 80:933-9. [DOI: 10.1016/j.theriogenology.2013.07.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 07/16/2013] [Accepted: 07/17/2013] [Indexed: 11/25/2022]
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Expanding possibilities for intervention against small ruminant lentiviruses through genetic marker-assisted selective breeding. Viruses 2013; 5:1466-99. [PMID: 23771240 PMCID: PMC3717717 DOI: 10.3390/v5061466] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/01/2013] [Accepted: 06/07/2013] [Indexed: 12/25/2022] Open
Abstract
Small ruminant lentiviruses include members that infect sheep (ovine lentivirus [OvLV]; also known as ovine progressive pneumonia virus/maedi-visna virus) and goats (caprine arthritis encephalitis virus [CAEV]). Breed differences in seroprevalence and proviral concentration of OvLV had suggested a strong genetic component in susceptibility to infection by OvLV in sheep. A genetic marker test for susceptibility to OvLV has been developed recently based on the TMEM154 gene with validation data from over 2,800 sheep representing nine cohorts. While no single genotype has been shown to have complete resistance to OvLV, consistent association in thousands of sheep from multiple breeds and management conditions highlight a new strategy for intervention by selective breeding. This genetic marker-assisted selection (MAS) has the potential to be a useful addition to existing viral control measures. Further, the discovery of multiple additional genomic regions associated with susceptibility to or control of OvLV suggests that additional genetic marker tests may be developed to extend the reach of MAS in the future. This review will cover the strengths and limitations of existing data from host genetics as an intervention and outline additional questions for future genetic research in sheep, goats, small ruminant lentiviruses, and their host-pathogen interactions.
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The risk of small ruminant lentivirus (SRLV) transmission with reproductive biotechnologies: State-of-the-art review. Theriogenology 2013; 79:1-9. [DOI: 10.1016/j.theriogenology.2012.09.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 09/21/2012] [Accepted: 09/29/2012] [Indexed: 11/18/2022]
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Can caprine arthritis encephalitis virus (CAEV) be transmitted by in vitro fertilization with experimentally infected sperm? Theriogenology 2012; 77:644-51. [DOI: 10.1016/j.theriogenology.2011.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 08/31/2011] [Accepted: 09/01/2011] [Indexed: 11/19/2022]
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Cortez-Romero C, Fieni F, Russo P, Pepin M, Roux C, Pellerin JL. Presence of Maedi Visna Virus (MVV)-Proviral DNA in the Genital Tissues of Naturally Infected Ewes. Reprod Domest Anim 2011; 46:e1-6. [DOI: 10.1111/j.1439-0531.2010.01608.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Romero CC, Pellerin J, Poulin N, Cognié Y, Chebloune Y, Pépin M, Fieni F. Maedi-Visna virus was detected in association with virally exposed IVF-produced early ewes embryos. Theriogenology 2010; 74:682-90. [DOI: 10.1016/j.theriogenology.2010.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 03/19/2010] [Accepted: 03/25/2010] [Indexed: 10/19/2022]
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Mahabir E, Bulian D, Needham J, Schmidt J. Lack of Transmission of Mouse Minute Virus (MMV) from In Vitro-Produced Embryos to Recipients and Pups Due to the Presence of Cumulus Cells During the In Vitro Fertilization Process. Biol Reprod 2009; 81:531-8. [DOI: 10.1095/biolreprod.109.077024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Minimum intravenous infectious dose of ovine progressive pneumonia virus (OPPV). Res Vet Sci 2009; 87:329-31. [PMID: 19246063 DOI: 10.1016/j.rvsc.2009.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Revised: 12/29/2008] [Accepted: 01/16/2009] [Indexed: 11/21/2022]
Abstract
The minimum intravenous infectious dose for ovine progressive pneumonia virus (OPPV) WLC1 was determined using twenty-four 6month-old lambs. Twelve groups of two 6month-old lambs were inoculated intravenously (i.v.) with tissue culture fluid containing ovine progressive pneumonia virus (OPPV) WLC1 titers ranging from 10(7.6) TCID(50)/lamb down to 10(-3.4) TCID(50)/lamb and were monitored for seroconversion using the OPPV agar gel immunodiffusion assay (AGID). Fifteen of the 16 lambs given equal or greater than 10(0.6) TCID(50) seroconverted, and virus could be isolated from peripheral blood leukocytes in 13 out of the 15 of these lambs. None of the eight lambs receiving less than 10(0.6) TCID(50) seroconverted during the 12months. The results of this study indicated that 10(0.6) or 4 TCID(50)/lamb given i.v. was capable of establishing infection.
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Abstract
RNA silencing is a common term for homology-dependent silencing phenomena found in the majority of eukaryotic species. RNA silencing pathways share several conserved components. The common denominator of these pathways is the presence of specific, short (21-25 nt) RNA molecules generated from different double-stranded RNA substrates by a specific RNase III activity. Short RNA molecules serve as a template for sequence-specific effects including transcriptional silencing, mRNA degradation, and inhibition of translation. This review will discuss possible roles of RNA silencing pathways in mouse oocytes and early embryos as well as the use of RNA silencing for experimental inhibition of gene expression in this model system.
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Herrmann-Hoesing LM, White SN, Lewis GS, Mousel MR, Knowles DP. Development and validation of an ovine progressive pneumonia virus quantitative PCR. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2007; 14:1274-8. [PMID: 17699832 PMCID: PMC2168119 DOI: 10.1128/cvi.00095-07] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ovine progressive pneumonia virus (OPPV) infects at least one sheep in 81% of U.S. sheep flocks, as determined by serology, and can cause viral mastitis, arthritis, dyspnea, and cachexia. Diagnostic tests that quantify OPPV proviral load in peripheral blood leukocytes (PBL) provide an additional method for identification of infected sheep and may help to further understanding of the pathogenesis of OPPV-induced disease. In this study, we compared a new OPPV real-time quantitative PCR (qPCR) assay specific for the transmembrane region of the envelope gene (tm) with a competitive inhibition enzyme-linked immunosorbent assay (cELISA) using 396 PBL samples and sera from Idaho sheep. The OPPV qPCR had a positive concordance of 96.2% +/- 2.3% and a negative concordance of 97.7% +/- 2.5% compared to the cELISA, with a kappa value of 0.93, indicating excellent agreement between the two tests. In addition, the presence of tm in the three OPPV qPCR-positive and cELISA-negative sheep and in 15 sheep with different OPPV proviral loads was confirmed by cloning and sequencing. These data indicate that the OPPV qPCR may be used as a supplemental diagnostic tool for OPPV infection and for measurement of viral load in PBLs of infected sheep.
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Affiliation(s)
- Lynn M Herrmann-Hoesing
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Washington State University, Pullman, WA 99164-6630, USA.
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