Fold increase of the percentage of CD8 + IFN-γ + within donor’s PBMCs of four major HLA class I after sensitization of candidate peptides. The percentage of CD8+IFN-γ+ from donor’s PBMCs of four major HLA class I were measured to determine whether the CD8+ CTL response were induced by sensitization of donor PBMCs with candidate peptides and the fold increase of the percentage of CD8+IFN-γ+ within the total CD8+ T cell population in donor PBMCs after re-sensitization of each candidate peptide were compared to that of negative control (PBMCs sensitized with no peptide). HPV18 E781-95DDLRAFQQLFLNTLS (#21) and E789-103LFLNTLSFVCPWCAS (#23) consistently induced higher the percentage of CD8+IFN-γ+ T cells than that of other candidate peptides in HLA-A*02:01 (A), HLA-A*24:02 (B), HLA-A*11:01 (C), HLA-A*33:03 (D). PBMCs sensitized with PHA were used as a positive control (PHA), and PBMCs sensitized with no peptide (No peptide) were used as the negative control (N.C). Data are presented as mean ± standard error.