Mouse peritoneal macrophages were grown in culture for 24 hours, stimulated with 10ng/mL IFN? and 1 ug/mL LPS for 14 hours and incubated for 4 hours with Bredfeldin A. Cells were harvested, washed, aliquoted 1x106 cells per sample, and fixed and permeabilized according to a standard protocol. Samples were stained with biotinylated primary anti-mouse p28 antibody at (0.1 - 10 ug/mL primary antibody alongside negative controls of unstimulated cells and isotype controls. Cells were stained with 0.25 ug/mL rat anti-mouse CD107b conjugated Alexa Fluor 647 and PHYCOERYTHRIN Conjugated secondary at 1:100 and analyzed by flow cytometry. Stimulated cells showed increase PE staining (horizontal axis) when compared with unstimulated cells.