Buthionine sulfoximine (BSO) depletes Jurkat T cell of GSH. Jurkat T cells treated with BSO for 24 hours were depleted of intracellular glutathione as determined by the GSH recycling assay (A). This was not associated with any loss in viability determined by trypan blue exclusion (B). The redox ratio of reduced to oxidised GSH was decreased by 50% after incubation with 25 μM BSO for 24 hours (C). The effect of BSO treatment on intracellular ROS was determined as DCF fluorescence after incubation with 25 μM BSO for 24 hours (D). Data represents the mean +/− SEM of three experiments where * represents p < 0.05.