Figure 4 . Modifying CTL: LCL ratio improves cytokine expression . T cell cultures from n=4 donors were split to directly compare stimulation round (SR) 2 and 3 of co-culture at standard (1 T cell : 5 LCL), or reduced intensity (1 T cell : 1 LCL). (A ) Fold expansion of viable lymphocytes between SR2 initiation (day 10) and end of SR3 (day 30) was calculated from viable cell count. (B ) Surface phenotype of final products remain comparable between the two groups for all markers analyzed. (C) Reduced intensity culture had a significantly higher cMFI of IFN-γ (p=0.00218) and TNF-α (p=0.0202) in response to stimulation (corrected to negative controls) compared to the standard ratio cultures.(D ) In CD8+/CD45RO+ T cells, there was an even distribution of Central Memory and Effector Memory compartments with reduced intensity conditioning, and a skew towards Effector Memory in standard process. Data is represented as mean ± SEM.