Hello, everyone. Recently, I have been stimulating jurkat cells to secrete IFN- γ, but jurkat cells were stimulated with 0, 1, 2, 2.5, 5 μ g / ml PHA or 0, 1, 2, 5, 10, 20 μ g / ml tuberculosis antigen peptides. After 24, 48 and 72 hours, no change of IFN- γ in the supernatant was detected by ELISA assay. At the same time, we prestimulated jurkat cells with PHA 2.5 μ g / ml for 24 hours. After 24, 48 and 72 hours of stimulation with tuberculosis antigen peptide, the change of IFN- γ was still not detected. We want to make jurkat cells react to tuberculosis antigen peptide and secrete IFN-- γ. Is there any good way to do that?