Description: The Protein Transport Inhibitor Cocktail (500X) is a cocktail of Brefeldin A and Monensin. It is suitable for use in assays in which prevention of protein transport to the extracellular space is desired and has been specifically formulated for use as a negative control for the Cell Stimulation Cocktail (plus protein transport inhibitors) (500X) (cat. 00-4975). Addition of this cocktail to cells in culture inhibits the intracellular protein secretory/transport pathway resulting in the accumulation of secreted proteins in the lumen of the endoplasmic reticulum and in the Golgi apparatus. This accumulation can then be detected by intracellular staining and flow cytometric analysis or western blotting.