Synthetic mast-cell granules as adjuvants to promote and polarize immunity in lymph nodes

Mast cells act to enhance immune responses through the release of insoluble granules that contain inflammatory mediators. Now, submicrometre polymer particles are shown to replicate and enhance the functions of mast-cell granules in vivo, such as the targeting of draining lymph nodes and the timed release of encapsulated mediators. The particles can also polarize the resulting immune response.