Fig. 6. Experimental validation of the TIL1383I specificity analysis.
In total, 72 peptides from the top 5% (scores ≥ 0.95) in the specificity analysis in Fig. 5f were selected for evaluation in co-culture experiments measuring IL-2 production. Peptides selected included the 24 highest-scoring peptides with two amino acid changes relative to the native Tyr370D peptide, the 24 highest-scoring peptides with three amino acid changes, and the 24 highest-scoring peptides with four amino acid changes. Five peptides at 50% (scores = 0.5, 6–7 amino acid changes) were also selected, as were the five lowest-scoring peptides (bottom 20%, scores = 0.19, 7 amino acid changes). The sequence of each peptide is listed. Amino acid changes relative to the Tyr370D peptide are in bold red font. The number of amino acid substitutions is given in the “# subs” column. IL-2 produced normalized to the amount produced by the WT peptide is colored red (maximum) to white (zero), along with the percent. The score from the fingerprint analysis is indicated by the “score” column. The estimated ΔG° (in kcal/mol) and KD for TCR binding, computed from the score as described in the Methods, are also indicated. “neg CTRL” indicates a negative control peptide unrelated to Tyr370D.