Affinity of p26, 18 and 23 binding to HLA-DR and HLA-DQ molecules
| DR1 | DR3 | DR4 | DR7 | DR9 | DR11 | DR13 | DR1501 | DR1502 | DQ6 | DQ8 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 14% | 30% | 20% | 25% | 1% | 14% | 16% | 27% | 2% | 16% | 21% | |
| p26 | 1 | 83 | 5 | 1 | 0.3 | 14 | 38 | 9 | 1 | 16 | 267 |
| p18 | 11 | nd | 0.3 | 32 | nd | 3 | >456 | 42 | 2000 | nd | nd |
| p23 | 1 | nd | 0.4 | 8 | nd | 2 | >456 | 37 | 4 | nd | nd |
Results are expressed as a relative binding ratio obtained by dividing the IC50 of allergen peptide by that of a reference peptide that binds strongly to the HLA molecule. Lower numbers correspond to a higher binding affinity. Numbers in bold (ratio of 20 or less) = high affinity binding; numbers in italic (ratio 20–100) = moderate binding affinity. Each peptide—major histocompatibility complex combination was evaluated in two independent experiments. Percentages are the frequency of the HLA-DR or HLA-DQ alleles in a Caucasian population calculated from allele frequency net (http://www.allelefrequencies.net): a database and online repository for immune gene frequencies in worldwide populations.
HLA, human leukocyte antigen; nd, not done.