Produção de imunobiológicos para o diagnóstico do vírus da bronquite infecciosa das galinhas

Abstract

The infectious bronchitis (IB) is a highly contagious viral disease that causes predominantly respiratory injuries that manifest clinically and invariably by sneezing and tracheo-bronchial throes and may lead to more severe signs with decreased fertility and reduced egg production. The infectious bronchitis virus (IBV) encodes four major structural proteins, the nucleoprotein being the most important in the immune response of the birds, since it is abundant and has a well conserved sequence. Vaccination is the primary means of disease control but outbreaks still occur frequently, causing major losses in poultry. As a result, the objective was to produce immunobiologicals that may contribute to the serological monitoring of birds. Therefore, the N protein was expressed in Escherichia coli, yielding a recombinant protein (RN) in soluble form. From this recombinant protein was a standard ELISA test and also produced monoclonal antibodies against rN. For the ELISA test were used 389 sera, which had been tested by the commercial kit, with the standardized ELISA and compared to IDEXX. The results obtained for the ELISA test showed a sensitivity of 90.16% and a specificity of 90.34% when compared to the commercial kit. For monoclonal antibodies, three primary hybridomas were selected, these being tested against different avian viruses. The produced monoclonal antibodies were specific to only recognize the virus bronchitis and recombinant protein (rN), with no cross-reactivity with other avian viruses. The inputs produced during work are promising for routine use in the laboratory that performs IB diagnostic.