Theileria
Theileria | |
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Kinete stage ofTheileria parvain the transmitting tickRhipicephalus appendiculatus | |
Scientific classification![]() | |
Domain: | Eukaryota |
Clade: | Diaphoretickes |
Clade: | SAR |
Clade: | Alveolata |
Phylum: | Apicomplexa |
Class: | Aconoidasida |
Order: | Piroplasmida |
Family: | Theileriidae |
Genus: | Theileria |
Species | |
Theileria annulata |
Theileriais a genus of parasites that belongs to thephylumApicomplexa,and is closely related toPlasmodium.TwoTheileriaspecies,T. annulataandT. parva,are important cattle parasites.[1]T. annulatacausestropical theileriosisandT. parvacausesEast Coast fever.Theileriaspecies are transmitted by ticks.[2] ThegenomesofT. orientalisShintoku[3],Theileria equiWA,[4]Theileria annulataAnkara[5]andTheileria parvaMuguga[6]have been sequenced and published.
Theileria equiis a known cause ofequine piroplasmosis.[7]
Vaccines againstTheileriaare in development.[1][8]In May 2010, a vaccine that was reported to protect cattle against East Coast fever had been approved and registered by the governments of Kenya, Malawi, and Tanzania.[9]
Description
[edit]Species in this genus undergo exoerythrocyticmerogonyin thelymphocytes,histiocytes,erythroblasts,and other cells of the internal organs. This is followed by invasion of the erythrocytes by themerozoites,which may or may not reproduce. When merogony does occur, no more than four daughter cells are produced. The frequent occurrence of elongated bacillary or "bayonet" forms within the erythrocyte is considered as characteristic of this genus.
The organism is transmitted by various tick species, includingRhipicephalus,Dermacentor,andHaemaphysalis.The organism reproduces in the tick as it progresses through its life stages.[10]BothT. annulataandT. parvainduce transformation of infected cells oflymphocyteormacrophage/monocyte lineages.T. orientalisdoes not induce uncontrolled proliferation of infected leukocytes and instead multiplies predominantly within infected erythrocytes.
Genomics
[edit]The genomes ofT. orientalisShintoku[3],Theileria equiWA,[4]Theileria annulataAnkara[5]andTheileria parvaMuguga[6]have been sequenced. Genomic data can be accessedPiroplasmaDBwhich is part of the Eukaryotic Pathogen Bioinformatic Resource (EuPathDB).[11]
Evolution
[edit]The genus is thought to have first appeared inruminantsduring theMiocene.It is named forGertrud Theiler,daughter ofArnold Theiler.
Transmission
[edit]Theileriaspp. can be transmitted to cattle through tick bites, including the brown ear tick, aRhipicephalussp.
Important species
[edit]- T. parvais the cause of bovinetheileriosisandEast Coast fever.[10]
- T. annulataalso is a cause of bovine theileriosis.[10]
- T. equicausesequine piroplasmosis.[10]It was originally classified asBabesia equiin 1901 byCharles Louis Alphonse Laveran,but was reclassified asT. equiin 1998 by Heinz Mehlhorn and Eberhard Schein.[12]
Treatment
[edit]- Buparvaquoneis a promising compound for the therapy and prophylaxis of all forms of theileriosis.
References
[edit]- ^abMorrison W, McKeever D (2006). "Current status of vaccine development againstTheileriaparasites ".Parasitology.133:S169–87.doi:10.1017/S0031182006001867.PMID17274845.S2CID928055.
- ^Florin-Christensen, M.; Schnittger, L. (Jan 2009)."Piroplasmids and ticks: a long-lasting intimate relationship".Frontiers in Bioscience.14(14): 3064–3073.doi:10.2741/3435.ISSN1093-9946.PMID19273257.
- ^abHayashida K, Hara Y, Abe T, Yamasaki C, Toyoda A, Kosuge T, Suzuki Y, Sato Y, Kawashima S, Katayama T, Wakaguri H, Inoue N, Homma K, Tada-Umezaki M, Yagi Y, Fujii Y, Habara T, Kanehisa M, Watanabe H, Ito K, Gojobori T, Sugawara H, Imanishi T, Weir W, Gardner M, Pain A, Shiels B, Hattori M, Nene V, Sugimoto C (2012)."Comparative genome analysis of three eukaryotic parasites with differing abilities to transform leukocytes reveals key mediators of Theileria-induced leukocyte transformation".mBio.3(5): e00204–12.doi:10.1128/mBio.00204-12.PMC3445966.PMID22951932.
- ^abKappmeyer, Lowell S.; Thiagarajan, Mathangi; Herndon, David R.; Ramsay, Joshua D.; Caler, Elisabet;Djikeng, Appolinaire;Gillespie, Joseph J.; Lau, Audrey OT; Roalson, Eric H. (2012-01-01)."Comparative genomic analysis and phylogenetic position of Theileria equi".BMC Genomics.13:603.doi:10.1186/1471-2164-13-603.PMC3505731.PMID23137308.
- ^abPain, Arnab; Renauld, Hubert; Berriman, Matthew; Murphy, Lee; Yeats, Corin A.; Weir, William; Kerhornou, Arnaud; Aslett, Martin; Bishop, Richard (2005-07-01). "Genome of the host-cell transforming parasite Theileria annulata compared with T. parva".Science.309(5731): 131–3.doi:10.1126/science.1110418.PMID15994557.S2CID34556923.
- ^abGardner, Malcolm J.; Bishop, Richard; Shah, Trushar; de Villiers, Etienne P.; Carlton, Jane M.; Hall, Neil; Ren, Qinghu; Paulsen, Ian T.; Pain, Arnab (2005-07-01). "Genome sequence of Theileria parva, a bovine pathogen that transforms lymphocytes".Science.309(5731): 134–7.doi:10.1126/science.1110439.PMID15994558.S2CID37769438.
- ^Englund, L. P. (2003). "New diseases and increased risk of diseases in companion animals and horses due to transport".Acta Veterinaria Scandinavica. Supplementum.100:19–25.ISSN0065-1699.PMID16429803.
- ^Darghouth, A. (Dec 2008). "Review on the experience with live attenuated vaccines against tropical theileriosis in Tunisia: considerations for the present and implications for the future".Vaccine.26. Suppl 6: G4–G10.doi:10.1016/j.vaccine.2008.09.065.ISSN0264-410X.PMID19178892.
- ^"Cattle disease vaccine launched 30 years after invention".2010-05-07.SciDev.net (7 May 2010).
- ^abcd*Theileriareviewed and published byWikiVet,accessed 11 October 2011.
- ^Harb, Omar S.; Roos, David S. (2015-01-01). "The Eukaryotic Pathogen Databases: A Functional Genomic Resource Integrating Data from Human and Veterinary Parasites".Parasite Genomics Protocols.Methods in Molecular Biology. Vol. 1201. pp. 1–18.doi:10.1007/978-1-4939-1438-8_1.ISBN978-1-4939-1437-1.PMC6157018.PMID25388105.
- ^Mehlhorn, Heinz; Schein, Eberhard (1998)."Redescription ofBabesia equiLaveran, 1901 asTheileria equiMehlhorn, Schein 1998 ".Parasitology Research.84(6): 467–475.doi:10.1007/s004360050431.PMID9660136.S2CID27992280.RetrievedJune 19,2020.
External links
[edit]- Theileria annulatasequencing project
- Theileria parvasequencing project
- Tropical theileriosis — Wellcome Trust project
- PiroplasmaDB— genomic and functional genomic resource forpiroplasmida