Majority of peptides binding HLA-A∗0201 with high affinity crossreact with other A2-supertype molecules

HLA class I-restricted responses to vaccinia recognize a broad array of proteins mainly involved in virulence and viral gene regulation

“…In the case of HLA A*0201, a dominant epitope [VWR082 (18)(19)(20)(21)(22)(23)(24)(25)(26)] was observed. Four of six donors recognized this epitope, and, in all four cases, the response to this epitope was greater than the response to all other A2-restricted epitopes recognized by the same donor.…”

A Quantitative Analysis of the Variables Affecting the Repertoire of T Cell Specificities Recognized after Vaccinia Virus Infection

“…Peptides used in initial screening experiments were synthesized as crude material by Mimotopes, Pepscan Systems, or A and A Labs, as described elsewhere (44). Peptides used as radiolabeled ligands for binding assays or used in immunizations were synthesized by A and A Labs and purified to Ͼ95% homogeneity by reverse-phase HPLC.…”

“…Quantitative assays to measure the binding affinity of peptides to purified HLA-A*0201 (A*0201) molecules are based on the inhibition of binding of a radiolabeled standard peptide and were performed as previously described (44,45). Briefly, 1-10 nM radiolabeled peptide was coincubated at room temperature with 1 nM-1 M purified MHC in the presence of 1-3 M human ␤ 2 -microglobulin (The Scripps Laboratory) and a mixture of protease inhibitors.…”

“…However, it was also noted that a significant proportion of binders do not strictly conform to canonical motifs, and were therefore missed. To overcome this limitation, the present analysis uses a very broad A*0201 motif previously characterized by our laboratory (44,52), which identifies peptides with L, I, V, M, A, T, or Q in position 2 and L, I, V, M, A, and T at the C terminus. This motif is present in 21 of 22 (95%) well-characterized EBV-, HIV-, influenza-, and tumor Ag-derived A*0201-restricted epitopes independently reported in the literature (see Supplemental Table IB).…”

Frontiers in peptide–MHC class II multimer technology

“…Are there also fundamental differences between MHC class I and II molecules in the strength of their binding interactions with peptides or TCRs? Binding studies of peptides with isolated class II MHC molecules indicate that, at least for certain strong-binding peptides, the IC50 (concentration needed to competitively inhibit 50% of the binding of a standard peptide) can be in the nanomolar range (L. Teyton, La Jolla, CA), similar to other reported pMHC class I and II interactions 10,11 . Dissociation constants of TCR-MHC class II interactions in the range of 10 × 10 -6 -35 × 10 -6 M (L. Stern, Cambridge, MA; E. Ward, Dallas, TX) are also similar to those reported for MHC class I-TCR binding 12 .…”