TL9-p24 and RM9-Nef immunodominance, pHLAI stability and differential selection pressure for HLA-B*07:02, HLA-B*42:01, HLA-B*42:02 and HLA-B*81:01. (A) Unbiased screening of n = 1,009 individuals with OLP-25 (GATPQDLNTMLNTVGGH) containing TL9-p24 and OLP-76 (EVGFPVRPQVPLRPMTFK) containing RM9-Nef of which n = 76 where HLA-B*07:02+, n = 154 where HLA-B*42:01+, n = 22 where HLA-B*42:02+ and n = 96 where HLA-B*81:01+. Individuals expressing HLA-B*39:10 (n = 30) were excluded as they also target TL9-24 and RM9-Nef. (B) TL9-p24 (TPQDLNTML) and RM9-Nef (RPQVPLRPM) pHLAI stability (binding half-life, h) against indicated HLA-B molecules. (C, D) CD thermal denaturation curves recorded at 218 nm are shown for selected pHLAI samples. Dots represent measured values fitted assuming a 2-state trimer-to-monomer transition (solid lines) as described in Methods. Insets show bar graphs of the thermal stability with respect to melting temperature (upper) and van’t Hoff’s enthalpy of unfolding (lower panel) using the same color code as in B. (E, F) Intraepitope HIV-1 polymorphisms for (E) TL9-p24 shown on the X-axis for Q182X as peptide position 3 and T186S as position 7 and (F) for RM9-Nef R71K as for peptide position 1 and L76X as position 6 and expressed as the percentage of total viral sequences for n = 1,327 HIV-1 infected individuals of which n = 189 expressed HLA-B*07:02, n = 436 expressed HLA-B*42:01, n = 56 expressed HLA-B*42:02 and n = 213 expressed HLA-B*81:01. Only Q < 0.05 is shown with ***indicating P < 0.0002 and **P < 0.002 compared to HLAI mismatched individuals.