CTL recognition of BL, HD, and LCL lines expressing EBV protein antigens from recombinant vaccinia vectors. (A) A B8-restricted EBNA 3A-specific CTL clone tested against OKU BL, HDLM2, and a B8-matched LCL target. (B) An A11-restricted EBNA 3B-specific CTL clone tested against KMH2 and L540. (C) An A2-restricted LMP 2-specific CTL clone tested against L1236. All targets had either been preincubated with the cognate peptide epitope or preinfected with a recombinant vaccinia vector expressing the target EBV protein. As controls, targets were preincubated with an equivalent dilution of DMSO solvent (−peptide) or with the vaccinia vector alone (control vacc). E:T ratios ranged from 5:1 to 10:1. All results are expressed as % specific lysis + 1 SD and are representative of several repeated assays.