Epitope characterization of MUC1 antibodies.
The 56 MAbs submitted to the ISOBM TD-4 Workshop were analysed by ELISA assay for reactivity against synthetic MUC1 mucin protein core-related peptides. With peptides comprising 5, 7 and 20 amino acids, 4/56 (7.1%), 33/56 (58.9%) and 51/56 (91.1%) of antibodies showed positive reactivity, respectively. Peptides with 60, 80, 100 and 120 amino acids showed 50/56 (98.2%), 54/56 (96.4%), 53/56 (94.6%) and 47/56 (83.9%) antibodies with positive reactivity, respectively. The reactivity of each MAb with synthetic peptides was classified into 3 groups. In group A (15 MAbs), the reactivity increased depending on the peptides in length and was maximal with 20-, 60-, 80-, 100- and 120-mer peptides. In group B (24 MAbs), most antibodies showed very weak binding affinity to peptides with a small increase in reactivity with the 100- and 120-mer peptides. In group C (17 MAbs), the reactivity showed strong binding affinity with the 20-mer peptide followed by a reduced uneven pattern of reactivity with the 60-, 80-, 100- and 120-mer peptides. These results show that the binding affinity of MAbs against synthetic peptides does not depend on the recognition of antibodies to the epitopes of core protein.
Imai
S
S
Nara Prefectural Institute of Public Health, Japan. simai@kyoto.macnet.or.jp
Haga
S
S
Kiyozuka
Y
Y
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000032:analysis*; D000918:Antibody Specificity / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology*; D008969:Molecular Sequence Data; D018396:Mucin-1 / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology*
D000911:Antibodies, Monoclonal; D016056:Immunodominant Epitopes; D018396:Mucin-1; D010446:Peptide Fragments