HLA-A2-binding peptides cross-react not only within the A2 subgroup but also with other HLA-A-locus allelic products.
Seven A2-binding peptides were tested by the HLA class I alpha-chain refolding assay previously described for their direct binding to HLA class I alpha chains derived from a panel of 18 HLA-homozygous B-cell lines of various HLA specificities, including four A2 subtypes: A*0201, A*0204, A*0205, and A*0206. All but one test peptide possessed the major anchor residue motifs, L-V, L-L, or I-L, of A2(A*0201)/A2(A*0205)-binding peptides or the closely related motifs, I-V or V-V. This cell panel analysis confirmed the high A2 allele specificity of the test peptides, but also revealed the existence of a broad cross-binding within the A2 subgroup. Most peptides bound to the alpha chains of the A2 subtypes tested, although their binding patterns showed differences. Furthermore, the A2-binding peptides carrying the I-V or V-V motif were found to cross-react also outside of the A2 subtypes, probably with A24, A26, A28, and A29. Other A-locus allelic products, A1, A3, A11, A30, and A31, and the B-locus allelic products carried by the cells tested were essentially negative, although a few exceptions were seen.
Tanigaki
N
N
Institute of Cellular Biology, CNR, Rome, Italy.
Fruci
D
D
Chersi
A
A
Falasca
G
G
Tosi
R
R
Butler
R H
RH
D000483:Alleles; D000595:Amino Acid Sequence; D002460:Cell Line; D003429:Cross Reactions / Q000502:physiology; D015234:HLA-A Antigens / Q000378:metabolism*; D015789:HLA-A2 Antigen / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology*; D011485:Protein Binding / Q000276:immunology
D015234:HLA-A Antigens; D015789:HLA-A2 Antigen; D010455:Peptides