LAUSR

Description B cell follicles in the lymph node protect vaccines to enhance immune responses After injection, vaccines drain to the lymph node, where naïve B cells in lymph node follicles recognize vaccine antigens, become activated, and mutate immunoglobulin genes to create protective antibodies. The remarkable success of vaccines suggests that this process occurs efficiently and results in antibodies against vaccine antigens that have retained their native structure. However, during the journey from injection site, vaccines must run a gauntlet of extracellular proteases before reaching follicular B cells. It is unclear how antigens are preserved as they are shepherded into B cell follicles and, after arrival, how they are maintained in a structurally intact conformation for continued B cell access. On page 350 of this issue, Aung et al. (1) reveal that lymph node B cell follicles in mice possess low intrinsic protease activity, allowing follicular dendritic cells (FDCs) to retain vaccine in its native form and potentially revealing ways to enhance vaccine efficacy.