LCLs present DEC-205–targeted EBV antigens efficiently to T-cell clones of different peptide specificities and HLA restrictions. (A) HLA-matched (Match) LCLs for EBNA1-specific CD4⁺ T-cell clones of 4 different epitopes (SNP, VYG, KTS, and PQC) were incubated with medium, 1 μg/mL control Ig-EBNA1 (+ TIB-E1), αDEC-205 without EBNA1 fusion (+ αDEC), αDEC-205-EBNA1 (+ αDEC-E1) for 24 hours, or for 1 hour with epitope-specific peptide (+ Peptide). An HLA mismatched target LCL was also included into the analysis (Mismatch). T cells were incubated with these targets at an E/T ratio of 1:1. T-cell activity was determined after 18 hours by measuring IFNγ released into the supernatant. (B) As in panel A, T-cell responses of EBNA1-specific CD8⁺ T-cell clones, HPVc35 and HPVc41, were tested against LCLs incubated without or with αDEC-EBNA1. (C) HLA-matched (Match) LCLs for 2 LMP1-specific CD4⁺ T-cell clones were incubated with medium, 1 μg/mL control Ig-LMP1 (+ Ctr-LMP1), αDEC-205 without LMP1 fusion (+ αDEC), αDEC-205-LMP1 (+ αDEC-LMP1) for 24 hours, or for 1 hour with epitope-specific peptide (+ Peptide). T-cell activity was determined as in panel A. One representative experiment of 4 per T-cell clone is shown. Statistical analysis of all available data from 4 independent experiments was performed by Mann-Whitney test and P values are represented as **P < .01, ***P < .005, and ****P < .0001.