Virus-specific cytotoxic T cells.
 (A) Generation of virus-specific cytotoxic T lymphocyte (CTL) by using plasmid system. (B) Specificity of plasmid-activated CTL. The frequency of Adv (Hexon and Penton), Epstein-Barr virus (EBV; LMP2 and BZLF1) and cytomegalovirus (CMV; pp65) reactive T cells in multivirus CTL population was analyzed by interferon (IFN)-γ Elispot assay. The control was IFN-γ release in response to stimulation with an irrelevant peptide mixture.