Characterisation of the factors that underpin the success of emergent group A Streptococcus variants using novel human tonsil infection models

The bacterium group A streptococcus (GAS) causes tonsillitis and skin conditions, as well as severe infections such as ‘flesh-eating’ disease. Sudden local and national increases in GAS disease are frequent, but the mechanisms behind these increases are unclear. Whole genome sequencing of strains responsible for upsurges in disease has revealed that major genetic changes can occur that result in an increased production of GAS toxins. A rise in toxin production may allow GAS to better initiate and maintain infections.

I will develop new laboratory-based models of human tonsil infection using human tonsil tissue obtained from routine tonsillectomies. I will use various culture techniques, including 3D tissue-engineering. These models will be used to study the critical interactions that allow GAS to cause infection, including the role of GAS toxins.

My findings will result in better understanding of what allows new strains of GAS to succeed in the human population and potential points that could be targeted for intervention.