EBV-CTLs transduced with CN mutants secrete normal levels of IFN-γ in the presence of CN inhibitors. EBV-CTL lines cultured in the presence of CN inhibitors for 2 weeks were stimulated with autologous LCLs, and IFN-γ secretion was assessed by ELISA 24 hours after stimulation. Median and interquartile range are shown (n = 5). CTLs transduced with CNa12 were able to secrete IFN-γ in the presence of 10 ng/mL FK506 at comparable levels to that seen with untransduced CTLs in the absence of CN inhibitors (mean, 66%) and CNa22-transduced CTLs secreted IFN-γ in the presence of 200 ng/mL CsA (mean, 66%). CNb30-transduced CTLs secreted IFN-γ with either FK506 (mean, 92%) or CsA (mean, 100%).