| Human T-lymphotropic virus |
| Virus classification |
| Group: |
Group VI (ssRNA-RT) |
| Family: |
Retroviridae |
| Subfamily: |
Orthoretrovirinae |
| Genus: |
Deltaretrovirus |
| Species: |
Simian T-lymphotropic virus |
| Serotypes |
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Human T-lymphotropic virus
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The Human T-lymphotropic virus Type I (HTLV-1) is a human RNA retrovirus that is known to cause a type of cancer, referred to as adult T-cell leukemia and lymphoma, and a demyelinating disease called HTLV-I associated myelopathy/Tropical spastic paraparesis (HAM/TSP). HTLV-I is one of a group of closely related primate T lymphotropic viruses (PTLVs). Members of this family that infect humans are called Human T-lymphotropic viruses, and the ones that infect old-world primates are called Simian T-lymphotropic viruses. To date, four types of HTLVs (HTLV-I, HTLV-II, HTLV-III, and HTLV-IV) and four types of STLVs (STLV-I, STLV-II, STLV-III, and STLV-IV) have been identified. The HTLVs are believed to originate from intraspecies transmission of STLVs. The original name for HIV, the virus that causes AIDS, was HTLV-III; this term is no longer in use [1]. The HTLV-1 genome is diploid, composed of two copies of a single-stranded RNA virus whose genome is copied into a double-stranded DNA form that integrates into the host cell genome, at which point the virus is referred to as a provirus. A closely related virus is bovine leukemia virus BLV.
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Contents
- 1 HTLV-I
- 2 HTLV-II
- 3 HTLV-III and HTLV-IV
- 4 Transmission
- 5 References
- 6 External links
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HTLV-I
Main article: Human T-lymphotropic virus 1
HTLV-I is an abbreviation for the human T-cell lymphotropic virus type 1, also called the Adult T-cell lymphoma virus type 1, a virus that has been seriously implicated in several kinds of diseases, including HTLV-I-associated myelopathy and Strongyloides stercoralis, and as a virus cancer link for leukemia (see adult T-cell leukemia/lymphoma). Between 1 in 20 and 1 in 25 infected persons are thought to develop cancer as a result of the virus.[citation needed][1]
HTLV-II
Main article: Human T-lymphotropic virus 2
A virus closely related to HTLV-I, HTLV-II shares approximately 70% genomic homology(structural similarity) with HTLV-I.
HTLV-III and HTLV-IV
When HIV, the virus that causes AIDS, was characterized in 1984 by Robert Gallo [2], he named it HTLV-III. HTLV-III is currently the name used to describe another virus related to HTLV-I and HTLV-II. "HTLV-IV" has been used to describe recently characterized viruses.[2][3][4]
These viruses were discovered in 2005 in rural Cameroon, and were, it is presumed, transmitted from monkeys to hunters of monkeys through bites and scratches.
- HTLV-III is similar to STLV-III (Simian T-lymphotropic virus 3).[5] Multiple strains have been identified.[6] It expresses gag, pol, and env, among other proteins.[7]
- HTLV-IV does not resemble any known virus.
It is not yet known how much further transmission has occurred among humans, or whether the viruses can cause disease.
The use of these names can cause some confusion, because the name HTLV-III was one of the names for HIV in early AIDS literature, but has since fallen out of use.[8] The name HTLV-IV has also been used to describe HIV-2.[9]
Transmission
HTLV-I and HTLV-II are sexually transmitted.[10][11]
References
- ^ WELSH, JAMES S. (January 2011). "Contagious Cancer". The Oncologist 16 (1): 1-4. doi:10.1634/theoncologist.2010-0301. PMID 21212437.
- ^ Mahieux, R; Gessain, A (2005). "Les nouveaux rétrovirus humains HTLV-3 et HTLV-4 [New human retroviruses: HTLV-3 and HTLV-4]" (in French). Médecine tropicale 65 (6): 525–8. PMID 16555510. http://www.revuemedecinetropicale.com/525-528_-_av_-_mahieux.pdf.
- ^ Calattini, S.; Chevalier, S. A.; Duprez, R.; Afonso, P.; Froment, A.; Gessain, A.; Mahieux, R. (2006). "Human T-Cell Lymphotropic Virus Type 3: Complete Nucleotide Sequence and Characterization of the Human Tax3 Protein". Journal of Virology 80 (19): 9876–88. doi:10.1128/JVI.00799-06. PMC 1617244. PMID 16973592. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1617244/.
- ^ Mahieux, R.; Gessain, Antoine (2009). "The human HTLV-3 and HTLV-4 retroviruses: New members of the HTLV family". Pathologie Biologie 57 (2): 161–6. doi:10.1016/j.patbio.2008.02.015. PMID 18456423.
- ^ MURPHEY-CORB, MICHAEL; LOUIS N. MARTIN, S. R. S. RANGAN, GARY B. BASKIN, BOBBY J. GORMUS, ROBERT H. WOLF, W. ABE ANDES, MELANIE WEST & RONALD C. MONTELARO (22). "Isolation of an HTLV-III-related retrovirus from macaques with simian AIDS and its possible origin in asymptomatic mangabeys". Nature 321 (321): 435 - 437. doi:10.1038/321435a0. http://www.nature.com/nature/journal/v321/n6068/abs/321435a0.html. Retrieved 10 May 2012.
- ^ Calattini, Sara; Betsem, Edouard; Bassot, Sylviane; Chevalier, SéBastien Alain; Mahieux, Renaud; Froment, Alain; Gessain, Antoine (2009). "New Strain of Human T Lymphotropic Virus (HTLV) Type 3 in a Pygmy from Cameroon with Peculiar HTLV Serologic Results". The Journal of Infectious Diseases 199 (4): 561–4. doi:10.1086/596206. PMID 19099485.
- ^ Chevalier, S. A.; Ko, N. L.; Calattini, S.; Mallet, A.; Prevost, M.-C.; Kehn, K.; Brady, J. N.; Kashanchi, F. et al. (2008). "Construction and Characterization of a Human T-Cell Lymphotropic Virus Type 3 Infectious Molecular Clone". Journal of Virology 82 (13): 6747–52. doi:10.1128/JVI.00247-08. PMC 2447071. PMID 18417569. //www.ncbi.nlm.nih.gov/pmc/articles/PMC2447071/.
- ^ Human+T-Lymphotropic+Virus+Type+III at the US National Library of Medicine Medical Subject Headings (MeSH)
- ^ Human+T+Lymphotropic+Virus+Type+IV at the US National Library of Medicine Medical Subject Headings (MeSH)
- ^ Rodriguez, Evelyn M.; de Moya, E. Antonio; Guerrero, Ernesto; Monterroso, Edgar R.; Quinn, Thomas C.; Puello, Elizardo; de Quiñones, Margarita Rosado; Thorington, Bruce et al. (1993). "HIV-1 and HTLV-I in sexually transmitted disease clinics in the Dominican Republic". Journal of acquired immune deficiency syndromes 6 (3): 313–8. PMID 8450407. http://journals.lww.com/jaids/Abstract/1993/03000/HIV_1_and_HTLV_I_in_Sexually_Transmitted_Disease.18.aspx.
- ^ Roucoux, Diana F.; Wang, Baoguang; Smith, Donna; Nass, Catharie C.; Smith, James; Hutching, Sheila T.; Newman, Bruce; Lee, Tzong-Hae et al. (2005). "A Prospective Study of Sexual Transmission of Human T Lymphotropic Virus (HTLV)-I and HTLV-II". The Journal of Infectious Diseases 191 (9): 1490–7. doi:10.1086/429410. PMID 15809908.
External links
- med/1038 at eMedicine - "human T-cell lymphotrophic virus"
- International Retrovirology Association
- Human+T-lymphotropic+virus+1 at the US National Library of Medicine Medical Subject Headings (MeSH)
- Human+T-lymphotropic+virus+2 at the US National Library of Medicine Medical Subject Headings (MeSH)
- Human T-Cell Leukemia/Lymphoma Virus Type 1: Playing Hide and Seek
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Virus: Retroviruses
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SsRNA-RT virus/
retroviridae |
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Alpharetrovirus
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- Avian sarcoma leukosis virus
- Rous sarcoma virus
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Betaretrovirus
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- Mouse mammary tumor virus
- Jaagsiekte sheep retrovirus
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Gammaretrovirus
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- Murine leukemia virus
- Abelson murine leukemia virus
- Friend virus
- Feline leukemia virus
- Koala retrovirus
- Xenotropic murine leukemia virus-related virus
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Deltaretrovirus
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- Human T-lymphotropic virus (HTLV-1
- HTLV-2)
- Bovine leukemia virus
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Epsilonretrovirus
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- Walleye epidermal hyperplasia virus
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Lentivirus
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- HIV
- Simian immunodeficiency virus
- Feline immunodeficiency virus
- Puma lentivirus
- Equine infectious anemia
- Bovine immunodeficiency virus
- Caprine arthritis encephalitis virus
- Visna virus
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Spumavirus
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- Simian foamy virus
- Human foamy virus
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Other
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- Metaviridae
- Pseudoviridae
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| DsDNA-RT virus |
- Hepadnaviridae (Hepatitis B virus)
- Caulimoviridae
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| Endogenous |
- ERVWE1
- HCP5
- Human teratocarcinoma-derived virus
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