Figure 3
From: Long-term adaptation of the influenza A virus by escaping cytotoxic T-cell recognition
Decrease in the number of predicted epitopes.
The change in number of top 5% strongest binding peptides in NP of H3N2 viruses for HLA-A (a) and HLA-B (b) alleles is shown over the period 1968–2015 (histograms; Methods). These peptides decrease in number for the large majority of HLA-B alleles (P = 0.006; mean change 
(95% CI: −15.6%, −2.6%) over the study period, Methods), but not for HLA-A alleles (P = 0.46). Despite the high level of heterogeneity in binding motifs, we find a decrease in the number of top-binders for a broad range of HLA-B alleles (Supplementary Fig. S12). The position of the twelve HLA supertype representatives are indicated with arrows. Fitted Gaussian curves indicate the decrease calculated for the thresholds ≤5%, ≤10% (top binders), and ≥50% (weak binders).
