Actinobacillus pleuropneumoniae (App) is the agent of contagious porcine pleuropneumonia: a widespread, severe and economically important respiratory disease of the pig. Apx (pore-forming) cytolysins are crucial for virulence. Protective immunity requires neutralizing antibody to the toxins, but vaccination with toxin fails to emulate this response. This project will aim to understand why the neutralizing response is poor and find ways to improve the response. Computational analysis will attempt to predict and understand toxin structure-function. Peptides will be designed to generate neutralizing response while excluding distracting regions. These will be tested by immunization of pigs and analysis of the cytolytic neutralizing response.
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