title: The African buffalo parasite Theileria. sp. (buffalo) can infect and immortalize cattle leukocytes and encodes divergent orthologues of Theileria parva antigen genes.
abstract: African Cape buffalo (Syncerus caffer) is the wildlife reservoir of multiple species within the apicomplexan protozoan genus Theileria, including Theileria parva which causes East coast fever in cattle. A parasite, which has not yet been formally named, known as Theileria sp. (buffalo) has been recognized as a potentially distinct species based on rDNA sequence, since 1993. We demonstrate using reverse line blot (RLB) and sequencing of 18S rDNA genes, that in an area where buffalo and cattle co-graze and there is a heavy tick challenge, T. sp. (buffalo) can frequently be isolated in culture from cattle leukocytes. We also show that T. sp. (buffalo), which is genetically very closely related to T. parva, according to 18s rDNA sequence, has a conserved orthologue of the polymorphic immunodominant molecule (PIM) that forms the basis of the diagnostic ELISA used for T. parva serological detection. Closely related orthologues of several CD8 T cell target antigen genes are also shared with T. parva. By contrast, orthologues of the T. parva p104 and the p67 sporozoite surface antigens could not be amplified by PCR from T. sp. (buffalo), using conserved primers designed from the corresponding T. parva sequences. Collectively the data re-emphasise doubts regarding the value of rDNA sequence data alone for defining apicomplexan species in the absence of additional data. 'Deep 454 pyrosequencing' of DNA from two Theileria sporozoite stabilates prepared from Rhipicephalus appendiculatus ticks fed on buffalo failed to detect T. sp. (buffalo). This strongly suggests that R. appendiculatus may not be a vector for T. sp. (buffalo). Collectively, the data provides further evidence that T. sp. (buffalo). is a distinct species from T. parva.
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: R P
authors.initials: RP
authors.lastname: Bishop
authors.affiliation: The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG Scotland, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Hemmink
authors.affiliation: The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG Scotland, UK.
authors.forename: W I
authors.initials: WI
authors.lastname: Morrison
authors.affiliation: College of Medical Veterinary and Life Sciences, University of Glasgow Glasgow, G61 1QH, UK.
authors.forename: W
authors.initials: W
authors.lastname: Weir
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: P G
authors.initials: PG
authors.lastname: Toye
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: T
authors.initials: T
authors.lastname: Sitt
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: P R
authors.initials: PR
authors.lastname: Spooner
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: A J
authors.initials: AJ
authors.lastname: Musoke
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya.
authors.forename: R A
authors.initials: RA
authors.lastname: Skilton
authors.affiliation: International Livestock Research Institute (ILRI), PO Box 30709, Nairobi, 00100, Kenya ; School of Biological Sciences, The University of Nairobi, PO Box 30197, Nairobi, 00100, Kenya.
authors.forename: D O
authors.initials: DO
authors.lastname: Odongo
keywords: 18S rDNA; Cape buffalo (Syncerus caffer); Deep sequencing; Polymorphic immunodominant molecule (PIM); Reverse line blot; Theileria parva; Theileria sp. (buffalo)