Immunogenicity and antigenicity of the recombinant EMA-1 protein of Theileria equi expressed in the yeast Pichia pastoris.

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.

Immunogenicity and antigenicity of the recombinant EMA-1 protein of Theileria equi expressed in the yeast Pichia pastoris / Imunogenicidade e antigenicidade da proteína recombinante EMA-1 de Theileria equi expressa em Pichia pastoris

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.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-1expressed in P. pastoris might be a strong candidate to be used as an antigen for immune diagnostics as well as a vaccine antigen.

A piroplasmose equina causada por Theileria equi é uma das mais importantes doenças parasitárias de equídeos, causando danos a saúde animal e perdas econômicas. Em T. equi, 2 proteínas de superfície de merozoítos, equi merozoite antigen EMA-1 e EMA-2, têm sido identificadas como antígenos imunodominantes. Sugerindo que estes antígenos possam ser usados como produtos imunobiológicos. O gene EMA-1 de T. equi foi clonado e expressado na levedura Pichia pastoris. As leveduras transformadas foram cultivadas a altas densidades celulares expressando 389 mg.L-1 de proteína recombinante. A proteína foi concentrada e detectada em Dot blot. O produto recombinante foi antigenicamente similar à proteína nativa quando determinado usando anticorpo monoclonal e anticorpos policlonais obtidos de equinos naturalmente infectados com T. equi. A imunogenicidade da proteína rEMA-1 foi demonstrada por RIFI utilizando soro de camundongos imunizados com proteína recombinante usando hidróxido de alumínio como adjuvante. Todos os animais vacinados com rEMA-1 desenvolveram uma alta resposta específica de anticorpos. Esses resultados sugerem que rEMA-1 expressa em P. pastoris possa ser um candidato para ser usado como antígeno para diagnóstico imunológico bem como antígeno para vacinas.

[Effects of the oxitetracycline in the increase of the packed cell volume of cows milk jugs during outbreak of bovine anaplasmosis]. / Efeitos da oxitetraciclina na recomposição do hematócrito de vacas leiteiras durante surto de anaplasmose bovina.

This research was performed to study the effects of oxytetracicline L.A., in unique dose, in the reconstitution of the packed cell volume (PCV) from animals clinically affected by anaplasmosis. Were utilized 152 Holstein Frisian Cows, of first lactation with age group varying between three and four years old. The animals were classified according to the presence of Anaplasma marginale in the circulation and percentage of PCV as: chronic infection (PCVe24%) and clinical (PCV<23%) constituting groups of 117 and 35, respectively. The animals with clinical infection were treated when detected the parasite by microscopy examination in stained thin blood smears and when the PCV were less than 24%; the animals with chronic infection were not treated and maintained like group control of the infection. All treated animals with 20mg.Kg-1 of oxitetracycline showed recuperation increasing for levels close to the physiological parameters. The animals considered with PCV normal for the category, in the day 0, were not treated and had tendency to the fall. The results reveal the activity of the oxytetraciclyne in the recuperation of clinical cases with anemia by bovine anaplasmosis.