VAMP2 and acute basophilic leukemia: Mast cells use the synaptosome-associated protein of 23 kDa (SNAP-23 or SN23) and syntaxin 4 (Syn4) as T-SNAREs localized on the plasma membrane during IgE-dependent degranulation, while several mRNAs encoding V-SNAREs including vesicle-associated membrane protein 2 (VAMP2), VAMP3, VAMP7, and VAMP8 have been reported to be expressed in rat basophilic leukemia (RBL-2H3) mast cells (18–20).