CTL Degranulation and Cytokine Secretion Assay

One day before the T-cell activation assays, human CTL were resuspended in Aim-V media containing 2% human serum without the addition of extra cytokines. Human CTL were counted and resuspended at a concentration of 10⁶ per ml, to which the following were added: anti-CD107a antibody (1:100), GolgiPlug Protein transport inhibitor (Brefeldin A, BD Bioscience, 1:1000). The growth media was removed from the culture plate containing CHO cells, and 200 μl of the human CTL mixture was added into each well of the 96-well plate. Technical triplicates were set for the experiments. The plate was incubated at 37 °C, 5% CO₂ for 3 h. Surface and intracellular staining were done according to the manufacturer’s protocol (BD Cytofix/Cytoperm, BD Perm/Wash, BD Biosciences)