Institute: University of Oxford
Development of a platform to investigate the antigen specificity of CD4 T cell responses to respiratory pathogens
Streptococcus pneumoniae (the pneumococcus) is the most common bacterial cause of pneumonia and meningitis in children and causes significant deaths in the elderly.
There are two types of pneumococcal vaccine – Pneumococcal Polysaccharide Vaccines (PPV) and Pneumococcal Conjugate Vaccines (PCV) – which are given based on age and health. But there is an increasing prevalence in pneumococcal disease caused by serotypes not covered by these vaccines. This combined with the emergence of antibiotic resistant strains make the development of new generation vaccines against pneumococcus a global health priority.
The development of these vaccines requires a better understanding of how cells of the immune system recognize and respond to the bacteria. The experimental human pneumococcal challenge (EHPC) model is at the moment uniquely established at the Liverpool School of Tropical Medicine, and represents an ideal way to investigate how colonization and vaccination modulate pneumococcal specific immune responses. However, studies addressing these questions are hampered by a lack of tools to identify pneumococcal specific responses induced upon colonization.
At the MRC Human Immunology Unit in Oxford, we have developed a single cell cloning approach to reconstruct in vitro the bacteria-specific CD4 T cells. This approach of analysing samples collected from volunteers challenged with pneumococcus in Liverpool will lead to the development of a tool box of reagents that could be used in future studies of pneumococcal colonization to identify broadly protective vaccine candidates.
More about Dr Napolitani here.