Secretion of intracellular contents is an essential component of cell function in health and disease. Cells of the immune system in particular, rely on secretion to perform their effector functions. Material transport between
cell compartments and to and from the cell surface is mediated by vesicles. Membrane anchored soluble N-ethylmaleimide-sensitive-factor attachment protein receptors (SNAREs) work to mediate vesicular docking and fusion to target membranes leading to secretion of contents. This function is especially important to cells that contain pre-made mediators in storage for immediate release upon demand, such eosinophils. SNAREs are categorized
by the conserved arginine (R-SNARE) or glutamine (Q-SNARE) residue in the central motif, and Q-SNAREs are
cytometry and pre-embedded immunonanogold electron microscopy, Carmo et al.Qa-SNARE, syntaxin17 (STX17), on the
membranes of secretory granules and eosinophil Sombrero vesicles (EoSV) of human eosinophils.