DRB1*0301 molecules recognize a structural motif distinct from the one recognized by most DR beta 1 alleles.
The DR3-restricted peptide, MT 65 kDa 3-13, was used to develop a DR3-specific binding assay. The binding activity detected was strictly pH-dependent, in that it was optimal in the pH 4 to 5 range, and no activity was detected at neutral pH. By means of affinity chromatography purifications and the use of DR3-transfected fibroblasts, it was shown that no cross-reactivity exists at the level of DR52a molecules, thus allowing use of only partially purified DR3/DR52a mixtures in high throughput binding assays. The immunologic relevance of the assay established was also verified by examining the correlation between DR3 restriction and binding for a panel of DR-restricted peptides. When the structural requirements for peptide DR3 interactions were further examined by using panels of analogues of two different epitopes (Myo 132-151 and TT 830-843), it was found that DR3 molecules recognized a peptide motif distinct from the one recognized by the other major DR beta 1 alleles.
Sidney
J
J
Cytel, San Diego, CA 92121.
Oseroff
C
C
Southwood
S
S
Wall
M
M
Ishioka
G
G
Koning
F
F
Sette
A
A
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D002874:Chromosome Mapping; D006684:HLA-DR Antigens / Q000235:genetics / Q000378:metabolism*; D059811:HLA-DRB1 Chains; D000949:Histocompatibility Antigens Class II / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D013329:Structure-Activity Relationship; D013745:Tetanus Toxoid / Q000378:metabolism
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553502:HLA-DRB1*03:01 antigen; D000949:Histocompatibility Antigens Class II; D010446:Peptide Fragments; D013745:Tetanus Toxoid