FIG. 4.
ELISPOT assays demonstrating that the shortest among equally optimal peptides for subject 20's dominant epitope present within the overlapping amino acids in the E6 26-40 and E6 31-45 regions is the E6 31-38 peptide. The bars represent standard errors of the means. (a) Clone #60-20 demonstrated large numbers of spot-forming units with E6 30-38 and E6 31-39 among the seven overlapping 9-mers covering the E6 26-40 region. The experiment was done in duplicates. (b) Clones #127-20 and #138-20 demonstrated large numbers of spot-forming units with E6 30-38 and E6 31-39 among the seven overlapping 9-mers covering the E6 31-45 region and the 15-mer. The experiment was done in duplicates. (c) Comparison of the E6 30-39 10-mer, E6 30-38 9-mer, E6 31-39 9-mer, E6 30-37 8-mer, E6 31-38 8-mer, E6 31-37 7-mer, and E6 32-38 7-mer revealed that the optimal peptide of minimum length is likely to be the E6 31-38 8-mer. The experiment was done in triplicates. (d) Comparison of the E6 30-39 10-mer, E6 30-38 9-mer, and E6 31-38 8-mer, ranging from 10−5 M to 10−10 M, showed that the minimal among three equally optimal peptides is the E6 31-38 8-mer peptide. The experiment was done in duplicates, and results with one representative clone (#60-20) out of two clones tested are shown.