title: Identification and characterization of merozoite antigens of a Theileria species highly pathogenic for small ruminants in China.
abstract: A new pathogenic Theileria species transmitted by Haemaphysalis qinghaiensis was identified in the Northwestern part of China and was shown to be highly pathogenic for small ruminants. The present article aimed at identifying merozoite antigens that might be suitable for developing diagnostic methods and designing a potential vaccine. Absence of other theilerial or babesial infections was confirmed by reverse line blot in all antigen samples used. Extensive Western blot analyses using serum from infected and noninfected animals led to the identification of four potential merozoite immunoreactive proteins at different molecular weights. Further protein characterization using peptide mass mapping by matrix-assisted laser desorption/ionization (MALDI) followed by database searching resulted in two significant hits that identified two proteins of parasite origin, one homologous to a possible MO25-family protein from Cryptosporidium parvum and the other with an HSP70 from Theileria annulata. Another protein was also identified as a parasite protein but without significant homology. Immunization of rabbits with selected proteins produced antisera that reacted specifically on Western blots with merozoite antigens of the corresponding sizes. This article represents the first identification and characterization of potential antigenic proteins of Theileria sp. (China) for veterinary purposes.
authors.affiliation: Instituto de Biologia Experimental e Tecnologica, Universidade Nova de Lisboa, Oeiras, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Miranda
authors.forename: Elisabete
authors.initials: E
authors.lastname: Nascimento
authors.forename: Helder
authors.initials: H
authors.lastname: Cruz
authors.forename: Yin
authors.initials: Y
authors.lastname: Hong
authors.forename: Ana
authors.initials: A
authors.lastname: Coelho
authors.forename: Jabbar S
authors.initials: JS
authors.lastname: Ahmed
authors.forename: Abel
authors.initials: A
authors.lastname: Oliva
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis*; D015153:Blotting, Western / Q000662:veterinary; D002681:China; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D007106:Immune Sera / Q000276:immunology; D026863:Ixodidae / Q000469:parasitology; D052940:Merozoites / Q000276:immunology; D008970:Molecular Weight; D015800:Protozoan Proteins / Q000032:analysis / Q000276:immunology; D016052:Protozoan Vaccines / Q000276:immunology; D011817:Rabbits; D012418:Ruminants / Q000469:parasitology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods / Q000662:veterinary; D016794:Theileria / Q000276:immunology* / Q000472:pathogenicity*; D013801:Theileriasis / Q000276:immunology*
chemical_list: D000953:Antigens, Protozoan; D007106:Immune Sera; D015800:Protozoan Proteins; D016052:Protozoan Vaccines