visna maedi virus

Summary

Summary: A species of LENTIVIRUS, subgenus ovine-caprine lentiviruses (LENTIVIRUSES, OVINE-CAPRINE), that can cause chronic pneumonia (maedi), mastitis, arthritis, and encephalomyelitis (visna) in sheep. Maedi is a progressive pneumonia of sheep which is similar to but not the same as jaagsiekte (PULMONARY ADENOMATOSIS, OVINE). Visna is a demyelinating leukoencephalomyelitis of sheep which is similar to but not the same as SCRAPIE.

Top Publications

  1. Duval R, Delebassee S, Cardot P, Bosgiraud C. Visna virus-induced cytopathic effect in vitro is caused by apoptosis. Arch Virol. 2002;147:943-59 pubmed
    ..In conclusion, our results suggest that VMV infection, in vitro, induces cell death of SCPC by a mechanism that can be characterized by many of the properties most closely associated with apoptotic cell death...
  2. Synge B. Testing for maedi-visna. Vet Rec. 2002;151:487 pubmed
  3. Reina R, Mora M, Glaria I, García I, Solano C, Lujan L, et al. Molecular characterization and phylogenetic study of Maedi Visna and Caprine Arthritis Encephalitis viral sequences in sheep and goats from Spain. Virus Res. 2006;121:189-98 pubmed
    ..This suggests that there is heterogeneity at the primer binding site among Spanish SRLV sequences. It also illustrates the need to develop diagnostic tests that are sensitive in local breeds...
  4. Herrmann Hoesing L, White S, Lewis G, Mousel M, Knowles D. Development and validation of an ovine progressive pneumonia virus quantitative PCR. Clin Vaccine Immunol. 2007;14:1274-8 pubmed
    ..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...
  5. Andrésson O, Elser J, Tobin G, Greenwood J, Gonda M, Georgsson G, et al. Nucleotide sequence and biological properties of a pathogenic proviral molecular clone of neurovirulent visna virus. Virology. 1993;193:89-105 pubmed
  6. Carrozza M, Mazzei M, Bandecchi P, Arispici M, Tolari F. In situ PCR-associated immunohistochemistry identifies cell types harbouring the Maedi-Visna virus genome in tissue sections of sheep infected naturally. J Virol Methods. 2003;107:121-7 pubmed
    ..This can be especially advantageous when the presence and localisation of the target sequence are investigated in the context of a tissue with its complex cellular organisation...
  7. Zhang Z, Watt N, Hopkins J, Harkiss G, Woodall C. Quantitative analysis of maedi-visna virus DNA load in peripheral blood monocytes and alveolar macrophages. J Virol Methods. 2000;86:13-20 pubmed
    ..The correlation of MVV load with pulmonary lesions suggests that infected alveolar macrophages play a key role in the pathogenesis of this lymphoid interstitial pneumonia...
  8. Saman E, Van Eynde G, Lujan L, Extramiana B, Harkiss G, Tolari F, et al. A new sensitive serological assay for detection of lentivirus infections in small ruminants. Clin Diagn Lab Immunol. 1999;6:734-40 pubmed
    ..6%). A limited set of goat sera (n = 212) was also analyzed, with similar results. These data indicate that the new assay is a reliable tool that can be used in control and eradication programs for small ruminant lentivirus infections...
  9. Harper A, Sudol M, Katzman M. An amino acid in the central catalytic domain of three retroviral integrases that affects target site selection in nonviral DNA. J Virol. 2003;77:3838-45 pubmed
    ..Moreover, this amino acid might be part of the cellular DNA binding site on integrase proteins...

More Information

Publications99

  1. Herrmann Hoesing L, White S, Mousel M, Lewis G, Knowles D. Ovine progressive pneumonia provirus levels associate with breed and Ovar-DRB1. Immunogenetics. 2008;60:749-58 pubmed publisher
    ..013-0.043) with higher OPP provirus levels. These results suggest that Ovar-DRB1 contributes as one host genetic factor that controls OPP provirus levels, but does not fully account for the breed-specific OPP proviral differences...
  2. Arsenault J, Dubreuil P, Girard C, Simard C, Bélanger D. Maedi-visna impact on productivity in Quebec sheep flocks (Canada). Prev Vet Med. 2003;59:125-37 pubmed
    ..65). The impact of MV infection on weaning weight and lamb mortality did not vary between flocks, and seropositivity in ewes was not associated with litter size or lamb's birth weight...
  3. Barber S, Bruett L, Douglass B, Herbst D, Zink M, Clements J. Visna virus-induced activation of MAPK is required for virus replication and correlates with virus-induced neuropathology. J Virol. 2002;76:817-28 pubmed
  4. Gonzalez B, Reina R, García I, Andrés S, Glaria I, Alzueta M, et al. Mucosal immunization of sheep with a Maedi-Visna virus (MVV) env DNA vaccine protects against early MVV productive infection. Vaccine. 2005;23:4342-52 pubmed
    ..Protection conferred by the vaccine could not be explained by OLA DRB1 allele or genotype differences. Most of the individuals were DRB1 heterozygous and none was totally resistant to infection...
  5. Grego E, Bertolotti L, Carrozza M, Profiti M, Mazzei M, Tolari F, et al. Genetic and antigenic characterization of the matrix protein of two genetically distinct ovine lentiviruses. Vet Microbiol. 2005;106:179-85 pubmed
  6. Kristbjörnsdóttir H, Andresdottir V, Svansson V, Torsteinsdottir S, Matthíasdóttir S, Andrésson O. The vif gene of maedi-visna virus is essential for infectivity in vivo and in vitro. Virology. 2004;318:350-9 pubmed
    ..These results suggest that the vif gene of MVV is essential for infectivity and that the Vif protein protects the viral genome from enpackaged mutagenic activities. ..
  7. Benavides J, García Pariente C, Ferreras M, Fuertes M, García Marín J, Perez V. Diagnosis of clinical cases of the nervous form of Maedi-Visna in 4- and 6-month-old lambs. Vet J. 2007;174:655-8 pubmed
    ..The investigation demonstrated that the clinical presentation of the nervous form of MV which is reported to occur in adult sheep can also be observed in young animals. ..
  8. Shah C, Huder J, Böni J, Schönmann M, Mühlherr J, Lutz H, et al. Direct evidence for natural transmission of small-ruminant lentiviruses of subtype A4 from goats to sheep and vice versa. J Virol. 2004;78:7518-22 pubmed
    ..These findings present for the first time direct evidence that natural interspecies transmission of SRLV is ongoing in both directions. The findings are of relevance to virus eradication programs in both species...
  9. Petursson G, Matthíasdóttir S, Svansson V, Andresdottir V, Georgsson G, Martin A, et al. Mucosal vaccination with an attenuated maedi-visna virus clone. Vaccine. 2005;23:3223-8 pubmed
  10. Villet S, Bouzar B, Morin T, Verdier G, Legras C, Chebloune Y. Maedi-visna virus and caprine arthritis encephalitis virus genomes encode a Vpr-like but no Tat protein. J Virol. 2003;77:9632-8 pubmed
    ..8-fold. Together, these data strongly suggest that the tat ORF in the SRLV genomes does not code for a regulatory transactivator of the LTR but, rather, for a Vpr-like accessory protein...
  11. Bruett L, Clements J. Functional murine leukemia virus vectors pseudotyped with the visna virus envelope show expanded visna virus cell tropism. J Virol. 2001;75:11464-73 pubmed
    ..The production of functional MuLV/visna virus pseudotypes has provided a sensitive, biologically relevant system to study visna virus cell entry and envelope-receptor interactions. ..
  12. Skinner L, Sudol M, Harper A, Katzman M. Nucleophile selection for the endonuclease activities of human, ovine, and avian retroviral integrases. J Biol Chem. 2001;276:114-24 pubmed
    ..These results indicate that interaction with target DNA is the critical step before catalysis and suggest that integrase does not reach an active conformation until target DNA has bound to the enzyme. ..
  13. Leginagoikoa I, Minguijon E, Juste R, Barandika J, Amorena B, de Andres D, et al. Effects of housing on the incidence of visna/maedi virus infection in sheep flocks. Res Vet Sci. 2010;88:415-21 pubmed publisher
  14. Gudmundsson B, Bjarnadottir H, Kristjansdottir S, Jonsson J. Quantitative assays for maedi-visna virus genetic sequences and mRNA's based on RT-PCR with real-time FRET measurements. Virology. 2003;307:135-42 pubmed
    ..These quantitative assays can be used to study the role of genetic elements in MVV infection and pathogenesis. They also allow rapid testing of lentiviral vectors and packaging systems based on MVV. ..
  15. Hötzel I, Cheevers W. Differential receptor usage of small ruminant lentiviruses in ovine and caprine cells: host range but not cytopathic phenotype is determined by receptor usage. Virology. 2002;301:21-31 pubmed
    ..Therefore, our results indicate that the differential species tropism of SRLV is determined by receptor usage. However, receptor usage is unrelated to cytopathic phenotype. ..
  16. Gudmundsson B, Jónsson S, Olafsson O, Agnarsdóttir G, Matthíasdóttir S, Georgsson G, et al. Simultaneous mutations in CA and Vif of Maedi-Visna virus cause attenuated replication in macrophages and reduced infectivity in vivo. J Virol. 2005;79:15038-42 pubmed
    ..These results suggest a functional interaction between CA and Vif in MVV replication, a property that may relate to the innate antiretroviral defense mechanisms in sheep. ..
  17. Pasick J. Maedi-visna virus and caprine arthritis-encephalitis virus: distinct species or quasispecies and its implications for laboratory diagnosis. Can J Vet Res. 1998;62:241-4 pubmed
    ..Implications for diagnostic testing and control of these diseases are discussed. ..
  18. Barros S, Andresdottir V, Fevereiro M. Cellular specificity and replication rate of Maedi Visna virus in vitro can be controlled by LTR sequences. Arch Virol. 2005;150:201-13 pubmed
    ..These observations suggest that the LTR is responsible for the slow/low in vitro phenotype presented by P1OLV in SCP and lung cells. ..
  19. Rosati S, Mannelli A, Merlo T, Ponti N. Characterization of the immunodominant cross-reacting epitope of visna maedi virus and caprine arthritis-encephalitis virus capsid antigen. Virus Res. 1999;61:177-83 pubmed
    ..Through the analysis of overlapping peptides spanning this region we identified a 17 amino acid sequence that can be used in the development of a highly standardized synthetic peptide-based assay...
  20. Henriques A, Fevereiro M, Prazeres D, Monteiro G. Development of a candidate DNA vaccine against Maedi-Visna virus. Vet Immunol Immunopathol. 2007;119:222-32 pubmed
    ..Stronger humoral responses were recorded by immunising mice with (i) Sc-p16 and lacZp16mut(24) plasmids together or with (ii) one plasmid containing both the mutations and the Sc signal. ..
  21. Woodall C, Watt N, Clements G. Simple technique for detecting RNA viruses by PCR in single sections of wax embedded tissue. J Clin Pathol. 1993;46:276-7 pubmed
    ..Various tissues were used which had not been deliberately prepared for this purpose. In a simple procedure hot xylene dewaxing is followed by acid phenol extraction of RNA and RNA PCR. ..
  22. Angelopoulou K, Brellou G, Vlemmas I. Detection of maedi-visna virus in the kidneys of naturally infected sheep. J Comp Pathol. 2006;134:329-35 pubmed
    ..These results suggest that the kidney may be a common target in natural MVV infection, and raise the issue of the role of this organ in the disease. ..
  23. Capucchio M, Sanna E, Sanna M, Farigu S, Minelli R, Guarda F. Maedi-visna virus detection in ovine third eyelids. J Comp Pathol. 2003;129:37-43 pubmed
    ..Immunohistochemistry demonstrated that the infection was productive. Taken together, these results indicate that the third eyelid may represent a target for natural MVV infection and may play a role in disease transmission...
  24. Berkowitz R, Ilves H, Plavec I, Veres G. Gene transfer systems derived from Visna virus: analysis of virus production and infectivity. Virology. 2001;279:116-29 pubmed
    ..Further modifications must be made to the Visna gene transfer system if the system is to be used in clinical gene therapy applications...
  25. Gelmetti D, Gibelli L, Brocchi E, Cammarata G. Using a panel of monoclonal antibodies to detect Maedi virus (MV) in chronic pulmonary distress of sheep. J Virol Methods. 2000;88:9-14 pubmed
  26. Celer V, Nejedlá E, Bertoni G, Peterhans E, Zanoni R. The detection of proviral DNA by semi-nested polymerase chain reaction and phylogenetic analysis of Czech Maedi-Visna isolates based on gag gene sequences. J Vet Med B Infect Dis Vet Public Health. 2000;47:203-15 pubmed
    ..The resulting phylogenetic tree of partial gag gene sequences confirmed that the ovine lentivirus genotype in the Czech Republic is more closely related to the prototype MVV isolates than to the caprine arthritis encephalitis viruses. ..
  27. Blacklaws B, Bird P, Allen D, Roy D, MacLennan I, Hopkins J, et al. Initial lentivirus-host interactions within lymph nodes: a study of maedi-visna virus infection in sheep. J Virol. 1995;69:1400-7 pubmed
    ..Virus-specific immune responses are therefore present within the node when infectious virus isolation is maximal, but cellular immunity may act to control the level of infection from day 18 onwards. ..
  28. Hötzel I, Cheevers W. A maedi-visna virus strain K1514 receptor gene is located in sheep chromosome 3p and the syntenic region of human chromosome 2. J Gen Virol. 2002;83:1759-64 pubmed
    ..These regions do not include any known lentivirus receptor or coreceptor gene, indicating that MVV-K1514 uses a new lentivirus receptor to infect human cells. ..
  29. Yilmaz H, Gurel A, Turan N, Bilal T, Kuscu B, Dawson M, et al. Abattoir study of maedi-visna virus infection in Turkey. Vet Rec. 2002;151:358-60 pubmed
  30. Bergsteinsdottir K, Arnadottir S, Torsteinsdottir S, Agnarsdottir G, Andresdottir V, Péttursson G, et al. Constitutive and visna virus induced expression of class I and II major histocompatibility complex antigens in the central nervous system of sheep and their role in the pathogenesis of visna lesions. Neuropathol Appl Neurobiol. 1998;24:224-32 pubmed
    ..Since the preferential induction of MHC antigens on microglia in the white matter correlated with the lesion pattern, activated microglia may play a considerable role in the pathogenesis of lesions...
  31. Preziuso S, Renzoni G, Allen T, Taccini E, Rossi G, DeMartini J, et al. Colostral transmission of maedi visna virus: sites of viral entry in lambs born from experimentally infected ewes. Vet Microbiol. 2004;104:157-64 pubmed
    ..The results contribute to knowledge about the pathogenesis of ovine lentivirus infection suggesting that the small intestine and mesenteric nodes are the sites of entry and propagation of MVV in lambs fed colostrums from infected ewes. ..
  32. Synge B, Baird G. Increased risk of maedi-visna. Vet Rec. 2002;150:615 pubmed
  33. Ryan S, Tiley L, McConnell I, Blacklaws B. Infection of dendritic cells by the Maedi-Visna lentivirus. J Virol. 2000;74:10096-103 pubmed
    ..The significance of the infection of afferent lymph dendritic cells is discussed in relation to the initial spread of lentivirus infection and the requirement for CD4 T cells. ..
  34. Schneider J, Kaaden O, Copeland T, Oroszlan S, Hunsmann G. Shedding and interspecies type sero-reactivity of the envelope glycopolypeptide gp120 of the human immunodeficiency virus. J Gen Virol. 1986;67 ( Pt 11):2533-8 pubmed
    ..Furthermore gp120 was precipitated by sera from horses infected with equine infectious anaemia virus (EIAV), but not by sera from uninfected animals. This may indicate conserved epitopes common to the envelopes of HIV and EIAV. ..
  35. Oskarsson T, Hreggvidsdottir H, Agnarsdóttir G, Matthíasdóttir S, Ogmundsdóttir M, Jónsson S, et al. Duplicated sequence motif in the long terminal repeat of maedi-visna virus extends cell tropism and is associated with neurovirulence. J Virol. 2007;81:4052-7 pubmed
    ..These results indicate that the duplication in the LTR is associated with neurovirulence...
  36. Harrington R, Herrmann Hoesing L, White S, O Rourke K, Knowles D. Ovine progressive pneumonia provirus levels are unaffected by the prion 171R allele in an Idaho sheep flock. Genet Sel Evol. 2009;41:17 pubmed publisher
    ..This study provides further support to the adoption of PRNP 171R selection as a scrapie control measure. ..
  37. Mariotti F, Preziuso S, Rossi G, Taccini E, Braca G, Renzoni G. CD4+CD25+ T cells in Maedi Visna infection: preliminary immunohistochemical study in experimentally infected sheep. Vet Res Commun. 2007;31 Suppl 1:237-9 pubmed
  38. Querat G, Audoly G, Sonigo P, Vigne R. Nucleotide sequence analysis of SA-OMVV, a visna-related ovine lentivirus: phylogenetic history of lentiviruses. Virology. 1990;175:434-47 pubmed
    ..BRU, ELI, and MAL HIV-1 isolates diverged in the early 1960s...
  39. Katzman M, Sudol M. Mapping viral DNA specificity to the central region of integrase by using functional human immunodeficiency virus type 1/visna virus chimeric proteins. J Virol. 1998;72:1744-53 pubmed
  40. Hare S, Di Nunzio F, Labeja A, Wang J, Engelman A, Cherepanov P. Structural basis for functional tetramerization of lentiviral integrase. PLoS Pathog. 2009;5:e1000515 pubmed publisher
    ..Our structures moreover highlight adaptable changes at the interfaces of individual IN dimers that allow divergent lentiviruses to utilize a highly-conserved, common integration co-factor...
  41. Preziuso S, Taccini E, Rossi G, Renzoni G, Braca G. Experimental Maedi Visna Virus Infection in sheep: a morphological, immunohistochemical and PCR study after three years of infection. Eur J Histochem. 2003;47:373-8 pubmed
  42. Leroux C, Vuillermoz S, Mornex J, Greenland T. Genomic heterogeneity in the pol region of ovine lentiviruses obtained from bronchoalveolar cells of infected sheep from France. J Gen Virol. 1995;76 ( Pt 6):1533-7 pubmed
    ..2-6.9%. Phylogenetic analysis showed that the French isolates form a group related to CAEV Co and distant from previously reported ovine lentivirus sequences from different origins...
  43. Philippon V, Vellutini C, Gambarelli D, Harkiss G, Arbuthnott G, Metzger D, et al. The basic domain of the lentiviral Tat protein is responsible for damages in mouse brain: involvement of cytokines. Virology. 1994;205:519-29 pubmed
    ..Blockade of TNF-alpha by a pentoxifylline treatment led to the decrease of IL-1 and iNOS expression accompanied by a reduction of the volume of the lesions indicating that the Tat-induced lesions might be mediated by TNF production...
  44. Zhang Z, Guo J, Ni Y, Bazer F, Giavedoni L, de la Concha Bermejillo A. Construction and characterization of a recombinant ovine lentivirus carrying the optimized green fluorescent protein gene at the dUTPase locus. Arch Virol. 2003;148:1485-506 pubmed
  45. Andresdottir V, Tang X, Agnarsdottir G, Andrésson O, Georgsson G, Skraban R, et al. Biological and genetic differences between lung- and brain-derived isolates of maedi-visna virus. Virus Genes. 1998;16:281-93 pubmed
    ..The molecular clone KV1772kv72/67 will be a useful reagent for characterization of viral determinants of cell tropism in vitro and possibly neurovirulence in vivo...
  46. Rolland M, Chauvineau C, Valas S, Mamoun R, Perrin G. Establishment and characterization of a goat synovial membrane cell line susceptible to small ruminant lentivirus infection. J Virol Methods. 2004;118:123-30 pubmed
    ..Such cell line provides a useful source of standard and robust cells for both research and veterinary purposes...
  47. Braun M, Clements J, Gonda M. The visna virus genome: evidence for a hypervariable site in the env gene and sequence homology among lentivirus envelope proteins. J Virol. 1987;61:4046-54 pubmed
    ..This correlation of hypervariability with lack of RNA secondary structure is strengthened by the fact that it also holds for a hypervariable site in the env gene of HIV...
  48. Varea R, Monleón E, Pacheco C, Lujan L, Bolea R, Vargas M, et al. Early detection of maedi-visna (ovine progressive pneumonia) virus seroconversion in field sheep samples. J Vet Diagn Invest. 2001;13:301-7 pubmed
    ..The ELISA was useful for detecting MVV-infected sheep in field conditions and has potential for use in control and eradication programs...
  49. Carrozza M, Mazzei M, Bandecchi P, Fraisier C, Perez M, Suzan Monti M, et al. Development and comparison of strain specific gag and pol real-time PCR assays for the detection of Visna/maedi virus. J Virol Methods. 2010;165:161-7 pubmed publisher
    ..The real-time assays developed in this study, particularly the gag assay, provide a sensitive tool which can be used to quantify the viral load in experimental infections...
  50. Niesalla H, de Andrés X, Barbezange C, Fraisier C, Reina R, Arnarson H, et al. Systemic DNA immunization against ovine lentivirus using particle-mediated epidermal delivery and modified vaccinia Ankara encoding the gag and/or env genes. Vaccine. 2009;27:260-9 pubmed publisher
  51. Reina R, Glaria I, Benavides J, de Andrés X, Crespo H, Solano C, et al. Association of CD80 and CD86 expression levels with disease status of Visna/Maedi virus infected sheep. Viral Immunol. 2007;20:609-22 pubmed
  52. Benavides J, Fuertes M, Garcia Pariente C, Ferreras M, García Marín J, Perez V. Natural cases of visna in sheep with myelitis as the sole lesion in the central nervous system. J Comp Pathol. 2006;134:219-30 pubmed
    ..Examination of paraffin wax-embedded samples by LTR-PCR and immunohistochemistry would seem useful in confirming a histopathological diagnosis of visna from spinal cord samples...
  53. Pisoni G, Bertoni G, Puricelli M, Maccalli M, Moroni P. Demonstration of coinfection with and recombination by caprine arthritis-encephalitis virus and maedi-visna virus in naturally infected goats. J Virol. 2007;81:4948-55 pubmed
    ..This case provides conclusive evidence that coinfection by different strains of SRLVs of groups A and B can indeed occur and that these viruses actually recombine in vivo...
  54. Shuaib M, Green C, Rashid M, Duizer G, Whiting T. Herd risk factors associated with sero-prevalence of Maedi-Visna in the Manitoba sheep population. Can Vet J. 2010;51:385-90 pubmed
    ..The study documented a remarkable stability of low seroprevalence in the province over a 20-year period in the absence of a systematic disease control program...
  55. Brinkhof J, Houwers D, Moll L, Dercksen D, van Maanen C. Diagnostic performance of ELISA and PCR in identifying SRLV-infected sheep and goats using serum, plasma and milk samples and in early detection of infection in dairy flocks through bulk milk testing. Vet Microbiol. 2010;142:193-8 pubmed publisher
    ..These results demonstrate the potential of bulk milk testing as a cost effective tool for early detection of infection in dairy flocks, which is essential for SRLV-monitoring programs...
  56. Bolea R, Monleón E, Carrasco L, Vargas A, de Andrés D, Amorena B, et al. Maedi-visna virus infection of ovine mammary epithelial cells. Vet Res. 2006;37:133-44 pubmed
  57. Fraisier C, Arnarson H, Barbezange C, Andresdottir V, Carrozza M, de Andrés D, et al. Expression of the gp150 maedi visna virus envelope precursor protein by mammalian expression vectors. J Virol Methods. 2007;146:363-7 pubmed
    ..These plasmid or viral expression vectors are of potential use in MVV vaccines...
  58. Villet S, Faure C, Bouzar B, Morin T, Verdier G, Chebloune Y, et al. Lack of trans-activation function for Maedi Visna virus and Caprine arthritis encephalitis virus Tat proteins. Virology. 2003;307:317-27 pubmed
    ..quot;..
  59. Krassnig R, Schuller W. [Continuation of the observation and serological investigation of a Maedi-Visna virus infected sheep flock from January 1990 to June 1996]. Dtsch Tierarztl Wochenschr. 1998;105:50-3 pubmed
    ..There was only seen a reduction of seropositive animals. Single results of serological tests, without knowing the sheep and the serological status of the herd, could pretend a false negative status...
  60. Plata F, Garcia Pons F, Ryter A, Lebargy F, Goodenow M, Dat M, et al. HIV-1 infection of lung alveolar fibroblasts and macrophages in humans. AIDS Res Hum Retroviruses. 1990;6:979-86 pubmed
    ..Alveolar macrophages and fibroblasts thus may act as eventual HIV-1 reservoirs in vivo, and are probably involved in the induction of inflammatory reactions because they are targets for CD8 cytotoxic T lymphocytes (CTL)...
  61. Salvatori D, Vincenzetti S, Maury G, Gosselin G, Gaubert G, Vita A. Maedi-visna virus, a model for in vitro testing of potential anti-HIV drugs. Comp Immunol Microbiol Infect Dis. 2001;24:113-22 pubmed
    ..All these data reveal a good correlation between inhibition of MVV replication by several nucleoside cytidine analogues and their reported anti-HIV activity...
  62. Biescas E, Preziuso S, Bulgin M, DeMartini J. Ovine lentivirus-associated leucomyelitis in naturally infected North American sheep. J Comp Pathol. 2005;132:107-16 pubmed
    ..The results confirm the usefulness of the IHC and ISH for differential diagnosis of visna...
  63. Boshoff C, Dungu B, Williams R, Vorster J, Conradie J, Verwoerd D, et al. Detection of Maedi-Visna virus antibodies using a single fusion transmembrane-core p25 recombinant protein ELISA and a modified receiver-operating characteristic analysis to determine cut-off values. J Virol Methods. 1997;63:47-56 pubmed
    ..The GST-TM-p25 ELISA was more sensitive than the commercial assay which is based on the p25 antigen alone and more specific than the GST-TM ELISA...
  64. Wagter L, Jansen A, Bleumink Pluym N, Lenstra J, Houwers D. PCR detection of lentiviral GAG segment DNA in the white blood cells of sheep and goats. Vet Res Commun. 1998;22:355-62 pubmed
    ..With the use of a set of mixed primers and probes, the assay was able to detect the variety of CAEV and MVV strains occurring in the field...
  65. Reina R, Barbezange C, Niesalla H, de Andrés X, Arnarson H, Biescas E, et al. Mucosal immunization against ovine lentivirus using PEI-DNA complexes and modified vaccinia Ankara encoding the gag and/or env genes. Vaccine. 2008;26:4494-505 pubmed publisher
    ..The results thus showed that protective effects against VMV-induced lesions can be induced following respiratory immunization with the single gag gene, though this was accompanied by an increased pulmonary provirus load...
  66. Laamanen I, Jakava Viljanen M, Sihvonen L. Genetic characterization of maedi-visna virus (MVV) detected in Finland. Vet Microbiol. 2007;122:357-65 pubmed
    ..The sequence analyses also showed that the virus had remained genetically relatively stable, in spite of the time given for virus evolution, an estimated 20 years, and in spite of the virus crossing the host species barrier...
  67. Peterhans E, Zanoni R, Bertoni G. How to succeed as a virus: strategies for dealing with the immune system. Vet Immunol Immunopathol. 1999;72:111-7 pubmed
    ..1995) or, more recently, the H5 subtype of influenza virus in humans (Shortridge et al., 1998). In addition, influenza viruses of birds may be transmitted, albeit only partially, through genetic reassortment (Shu et al., 1996)...
  68. Brellou G, Angelopoulou K, Poutahidis T, Vlemmas I. Detection of maedi-visna virus in the liver and heart of naturally infected sheep. J Comp Pathol. 2007;136:27-35 pubmed
    ..These novel findings suggest that, although the macrophage is the main cell for productive viral replication, the liver and heart represent additional MVV targets...
  69. Singh I, McConnell I, Blacklaws B. Immune response to individual maedi-visna virus gag antigens. J Virol. 2006;80:912-9 pubmed
    ..All three gag antigens may therefore play a role in immune-mediated lesion formation in MVV disease by presentation on infected macrophages in lesions...
  70. Blazek D, Celer V, Navratilova I, Skladal P. Generation and characterization of single-chain antibody fragments specific against transmembrane envelope glycoprotein gp46 of maedi-visna virus. J Virol Methods. 2004;115:83-92 pubmed
    ..The application of characterized scFvs for expression as intrabodies in intracellular immunization against virus maedi-visna infection and for the diagnosis of this virus is discussed...
  71. Benavides J, Garcia Pariente C, Fuertes M, Ferreras M, García Marín J, Juste R, et al. Maedi-visna: the meningoencephalitis in naturally occurring cases. J Comp Pathol. 2009;140:1-11 pubmed publisher
    ..Cells consistent with macrophages and shown immunohistochemically to be associated with MV virus were seen in malacic and infiltrative lesions, at the periphery of damaged areas...
  72. de Andrés X, Reina R, Ciriza J, Crespo H, Glaria I, Ramirez H, et al. Use of B7 costimulatory molecules as adjuvants in a prime-boost vaccination against Visna/Maedi ovine lentivirus. Vaccine. 2009;27:4591-600 pubmed publisher
    ..Thus, the inclusion of B7 genes helped to enhance early cellular responses and protection (diminished proportion of infected animals) against VMV infection...
  73. Starick E, Dedek J, Enke K, Loeppelmann H. [Serologic investigations on the occurrence of Maedi-Visna antibodies in game ruminants]. Dtsch Tierarztl Wochenschr. 1995;102:202-3 pubmed
    ..While about 27% of sheep herds have been shown to be MVV positive, no wild animal serum has been reacted with any of the antigens...
  74. Stephens R, Casey J, Rice N. Equine infectious anemia virus gag and pol genes: relatedness to visna and AIDS virus. Science. 1986;231:589-94 pubmed
    ..Within the family, EIAV, HTLV-III, and visna appear to be equally divergent from a common evolutionary ancestor...
  75. Gourdou I, Mabrouk K, Harkiss G, Marchot P, Watt N, Hery F, et al. [Neurotoxicity in mice due to cysteine-rich parts of visna virus and HIV-1 Tat proteins]. C R Acad Sci III. 1990;311:149-55 pubmed
    ..The HIV-1 recombinant Tat protein has the same effect. Such observation suggests a direct role of the Tat lentiviral protein in the origin of the neurologic effects associated with visna and HIV-1 infections...
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