Mast cells are multifunctional master cells implicated in both innate and adaptive
immune responses. Their role has been best characterized in allergy and anaphylaxis;
however, emerging evidences support their contribution to a wide variety of human
diseases. Mast cells, being capable of both degranulation and subsequent recovery,
have recently attracted substantial attention as also being rich sources of secreted
extracellular vesicles (including exosomes and microvesicles). Along with secreted
de novo synthesized soluble molecules and secreted preformed granules, the membrane-enclosed
extracellular vesicles represent a previously unexplored part of the mast cell secretome.
In this review article we summarize available data regarding the different soluble
molecules and membrane-enclosed structures secreted by mast cells. Furthermore, we
provide an overview of the release mechanisms including degranulation, piecemeal degranulation,
transgranulation, and secretion of different types of extracellular vesicles. Finally,
we aim to give a summary of the known biological functions associated with the different
mast cell-derived secretion products. The increasingly recognized complexity of mast
cell secretome may provide important novel clues to processes by which mast cells
contribute to the development of different pathologies and are capable of orchestrating
immune responses both in health and disease.
