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| | + | {{frontpage |
| | + | |pagetitle =Retroviridae |
| | + | |pagebody = Retroviruses are persistent, non-cytopathic, systemic viruses that give rise to secondary disease, such as tumors, immune-complex disease, or immunosuppression. |
| | + | |contenttitle =Content |
| | + | |contentbody =<big><b> |
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| | + | <categorytree mode=pages>Retroviridae</categorytree> |
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| − | [[File:FeLV logo.jpg]]
| + | |logo =FeLV logo.jpg |
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| | + | {{Learning |Vetstream = <p>[https://www.vetstream.com/felis/Content/Bug/bug60015.asp Feline Immunodeficiency Virus]</p><p>[https://www.vetstream.com/felis/Content/Bug/bug60014.asp Feline Leukemia Virus]</p>}} |
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| − | =Introduction=
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| − | Retroviruses are persistent, non-cytopathic, systemic viruses that give rise to secondary disease, such as tumors, immune-complex disease, or immunosuppression.
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| − | =Morphology=
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| − | *Fragile, enveloped RNA viruses with roughly spherical spike proteins
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| − | *Genome has 3 genes:
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| − | **''gag'': group-specific antigen coding gene, encodes capsid proteins
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| − | **''pol'': encodes reverse transcriptase (RT) and integrase
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| − | **''env'': encodes envelope spikes, and can be used in diagnosis and subunit vaccines
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| − | *Both ends of genome show a promoter (LTR: long terminal repeat)
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| − | =Antigenicity=
| + | [[Category:Viral Organisms]] |
| − | *Group-specific antigens (gag's) are shared by all isolates of each virus
| + | [[Category:To_Do_-_Clinical/Viruses]] |
| − | **This can be exploited by diagnostic tests
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| − | *Lentiviruses show variation by mutation, making vaccination difficult
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| − | =Virulence and Pathogenesis=
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| − | *Replication involves integrating into the host cell genome:
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| − | **'''Uncoating''' to release RNA and RT
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| − | **+RNA '''transcribed''' to -DNA by RT
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| − | **-DNA becomes circular dsDNA and is '''integrated''' into host chromosome by integrase
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| − | **DNA '''codes''' for viral proteins using cellular organelles and enzymes
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| − | **Because of this technique, virus replication is much '''slower''', and retroviruses can remain '''latent'''
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| − | *Tumor production takes 2 forms:
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| − | **Viruses can carry oncogenes within their genome --> tumor production occurs quickly
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| − | **Insertion of the viral LTR switches on proto-oncogenes in the host cell genome --> tumor production can take years
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| − | =Types and Subtypes=
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| − | 7 Genera, including these of veterinary relevance:
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| − | #[[Mammalian Type C retrovirus]]
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| − | #[[Mammalian Type D retrovirus]]
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| − | #
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| − | #[[Avian Type C retrovirus]]
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| − | #
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| − | #[[Spumavirus]]
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| − | #BLV-HTLV retroviruses
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| − | #*Bovine Leukosis Virus
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| − | #Lentiviruses
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| − | #*[[Feline Immunodeficiency Virus (FIV)]]
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| − | #*Bovine Immunodeficiency Virus
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| − | #*[[Visna-Maedi Virus of Sheep]]
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| − | #*[[Caprine Arthrirtis Encephalitis Virus]]
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| − | #*[[Equine Infectious Anemia]]
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| − | #*Jembrana of Bali cattle
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| − | #*Human Immunodeficiency Virus (HIV)
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| − | [[Category:Viruses]] | |