Table I.
Peptides used for the generation of HLA-DR tetramersa
| HLA-DR Allele | Peptide Residues | Abbreviation | Sequence | IC50 (μM) | Loading Efficiency (%) |
|---|---|---|---|---|---|
| DRB1*0101 | CLIP (87–101) | CLIP | PVSKMRMATPLLMQA | ND | ND |
| p24 (33– 46) | p24 –1 | SPEVIPMFSALSEG | 2.3 | 80 | |
| p24 (138 –150) | p24 –3 | LNKIVRMYSPTSI | 1.9 | 53 | |
| p24 (166 –179) | p24 – 4 | DRFYKTLRAEQASQ | 4.5 | 100 | |
| DRB1*0401 | Annexin II (208 –223) | Ann II | DVPKWISIMTERSVPH | 0.58 | 95 |
| p24 (33– 46) | p24 –1 | SPEVIPMFSALSEG | 0.7 | 87 | |
| p24 (113–127) | p24 –2 | EQIGWMTNNPPIPVG | 5 | 78 | |
| p24 (138 –150) | p24 –3 | LNKIVRMYSPTSI | 3 | 90 | |
| p24 (166 –179) | p24 – 4 | DRFYKTLRAEQASQ | 2 | 99 | |
| DRB1*1501 | PLP (90 –109) | PLP | FYTTGAVRQIFGDYKTTICG | ND | 77 |
| p24 (33– 46) | p24 –1 | SPEVIPMFSALSEG | 0.68 | 63 | |
| p24 (138 –150) | p24 –3 | LNKIVRMYSPTSI | 0.22 | 59 | |
| DRB5*0101 | Annexin II (208 –223) | Ann II | DVPKWISIMTERSVPH | 1.8 | 27 |
| p24 (166 –179) | p24 – 4 | DRFYKTLRAEQASQ | 2 | 79 |
A total of 10 tetramers were generated with four distinct HIV p24 peptides and four different HLA-DR molecules. The peptides were identified as ligands for the respective HLA-DR molecule in a competition assay, and the IC50 values from these experiments are listed. HLA-DR molecules with bound peptides from self-proteins were used as controls, the invariant chain-derived CLIP peptide, as well as peptides from annexin II (Ann II) and proteolipid protein (PLP). HIV, annexin, and proteolipid protein peptides carried an N-terminal affinity tag (DNP), and HLA-DR molecules loaded with these peptides were affinity purified using an anti-DNP column. The loading efficiency represents the fraction of HLA-DR that bound to the anti-DNP column.