title: Immunogenicity and antigenicity of the recombinant EMA-1 protein of Theileria equi expressed in the yeast Pichia pastoris.
abstract: The equine piroplasmosis caused by Theileria equi is one of the most important parasitic diseases of the equine, causing damage to animal health and economic losses. In T. equi, 2 merozoite surface proteins, equi merozoite antigen EMA-1 and EMA-2, have been identified as the most immunodominant antigens. This suggests that these antigens might be used as immunobiological tools. The EMA-1 of Theileria equi was cloned and expressed in the yeast Pichia pastoris. The transformed yeast was grown at high cell density, expressing up to 389 mg x L(-1) of recombinant protein. The protein was concentrated and detected in Dot blot. The recombinant product was antigenically similar to the native protein as determined using monoclonal antibodies, and polyclonal antibodies obtained from equines naturally infected with T. equi. The immunogenicity of rEMA-1 protein was demonstrated by IFAT using sera from recombinant-protein-immunized mice using aluminum hydroxide as adjuvant. All animals vaccinated with rEMA-1 developed a high specific antibody response. This results suggest that rEMA-1 expressed in P. pastoris might be a strong candidate to be used as an antigen for immune diagnostics as well as a vaccine antigen.
authors: Centro de Biotecnologia, Universidade Federal de Pelotas - UFPel, Rua Gomes Carneiro 1, Centro, CP 354, CEP 96010-610 Pelotas - RS, Brazil. lqn@pop.com.br
authors: Leandro Q
authors: LQ
authors: Nizoli
authors: Fabrício R
authors: FR
authors: Conceição
authors: Sérgio S
authors: SS
authors: Silva
authors: Luana A
authors: LA
authors: Dummer
authors: Alceu G
authors: AG
authors: Santos
authors: Fábio P L
authors: FP
authors: Leite
mesh_terms: D000818:Animals; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D010843:Pichia / Q000378:metabolism*; D015800:Protozoan Proteins / Q000096:biosynthesis* / Q000276:immunology*; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000276:immunology*; D016794:Theileria
chemical_list: D015800:Protozoan Proteins; D011994:Recombinant Proteins