Investigating the immune response to Group A Streptococcus

BACKGROUND
Streptococcus pyogenes, also known as Group A Streptococcus (GAS), is a bacterium that causes disease in humans (a pathogen). It usually causes mild illnesses, such as sore throat, but can also cause severe illnesses, such as toxic shock syndrome. Additionally, in some cases, mild GAS infections can trigger the development of rheumatic heart disease, which is a severe complication that causes irreversible damage to the heart. Each year, over 500,000 people die from GAS infections worldwide. To prevent these deaths, we need to find ways to stop GAS infections from occurring in the first place.

One strategy for preventing GAS infections is vaccination. Vaccines either contain a weakened form of the target pathogen or, alternatively, just a small component of the pathogen. Unlike the pathogen itself, vaccines don't cause disease. However, they do train the body's immune system to recognise and fight off the pathogen. This means that if we come across that pathogen in the future, we won't get ill.

When developing a vaccine, it is important that we know what our body's natural immune response to the target pathogen is. This information helps us understand what type of vaccine will best train our body's immune system to fight off that pathogen. In the case of GAS, we know that adults get fewer GAS infections than children. This suggests there is something about the immune response in adults that makes them better able to fight off this pathogen. Finding out what this is will be key in helping vaccine development efforts.

AIMS & OBJECTIVES
This project therefore aims to study natural immune responses to GAS in adults. We will focus on antibody responses, as previous research has suggested that this part of the immune system is particularly important in protecting against GAS infections. Therefore, by investigating antibody responses to GAS in adults, we hope to better understand what kind of vaccine is needed to protect against this pathogen.