Ageing and the Germinal Centre Response
At the heart of the immune response to vaccination is the germinal centre (GC) – a dynamic structure that forms in secondary lymphoid tissues after immunisation, and produces long-lived plasma cells, which secrete antibodies that block pathogens from establishing an infection, and memory B cells. A defining property of the GC is the collaboration of multiple cell types: proliferating B cells, T follicular helper cells, T follicular regulatory cells and follicular dendritic cells to produce effector B cells of higher quality. With age, the magnitude of the GC response decreases resulting in impaired production of plasma cells, lower serum antibody levels and consequently, decreased protection against subsequent infection. Despite the key role of B cells in the GC, their function does not decline with age, and they are not responsible for the impaired germinal centre response in older individuals. This talk will discuss the cellular and molecular mechanisms that underpin the poor GC response in older individuals.