Roles of mast cells and basophils in innate and acquired immunity.

There have been several recent advances in knowledge about mast cells and basophils in immune responses, of which some are particularly important: a role has been found for heparin in the storage of certain proteases and other mediators in mast cell cytoplasmic granules; an important role for mast cells in the development of several chronic aspects of an asthma model in mice has been discovered; and a new approach has been developed, based on the generation of mast cells from embryonic stem cells in vitro, to investigate mast cell function in vitro or in vivo.