Protecting Pigs From Enzootic Pneumonia: Rational Design Of Safe Attenuated Vaccines.

Mycoplasma hyopneumoniae is the primary cause of enzootic pneumonia, a worldwide respiratory disease of pigs that has a major impact on the growth and welfare of animals. Despite its economic importance, the pathogen itself is hard to culture in vitro and difficult to manipulate genetically. This study will build on previous world-leading BBSRC funded research which provided preliminary data identifying genes non-essential for growth of the bacteria in vitro but essential in vivo. The study will focus on the identification of strains with potential to be the basis of improved vaccines. We will confirm whether attenuated strains are able to colonise the lungs of pigs and, when they are present whether they are able to cause lesions using a modified TraDis approach. This proposal will also develop a toolkit of reagents and methods suitable for the modification of strains of the bacteria isolated from UK pigs to ensure that vaccine strains are a close match for those currently circulating in animals. Major outputs will include identification of genes which result in attenuation of the bacteria in pigs and an assessment of the efficacy and safety of modified M.hyop strains as vaccine candidates, with the ultimate aim of bridging the gap between tool development and practical use in the form of a proof-of-concept challenge study. The study addresses an unmet need in the swine and pharmaceutical industries for improved immunogens for M.hyop and better methods to produce attenuated strains of bacteria suitable for further development.