Monoclonal antibodies reactive with the breast carcinoma-associated mucin core protein repeat sequence peptide also recognise the ovarian carcinoma-associated sebaceous gland antigen.
The monoclonal antibody (Mab) OM-1, which defines the ovarian carcinoma-associated sebaceous gland antigen (SGA), and Mab F36/22, which defines the ductal carcinoma antigen (DCA), were tested for reactivity against a synthetic peptide representing the repeat twenty amino acid sequence of the human polymorphic epithelial mucin core protein plus four amino acids of the adjacent sequence (p1-24). OM-1 bound strongly to the peptide by direct dot blot assay and ELISA and the minimum epitope for OM-1 was shown to be APDTRP(A) by inhibition assay. F36/22 reacted weakly with the peptide under the same conditions and its affinity for peptide in solution was relatively very low. Mab OC125, which defines the ovarian cancer-associated antigen CA125, did not react with the p1-24 peptide. Five other anti-mucin Mabs (HMFG1, HMFG2, BC1, BC2, BC3), previously shown to bind to the p1-24 peptide, reacted strongly with SGA by direct binding and in a sandwich assay with OM-1 as the capture Mab. F36/22 was weakly positive under the same conditions suggesting that both peptide and SGA do not express the optimal epitope for F36/22 binding. These results indicate that SGA and possibly DCA have the repeat sequence core protein of the breast carcinoma-associated human polymorphic epithelial mucin.
Layton
G T
GT
Medical Innovations Limited, Labrador, Qld., Australia.
Devine
P L
PL
Warren
J A
JA
Birrell
G
G
Xing
P X
PX
Ward
B G
BG
McKenzie
I F
IF
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity / Q000276:immunology; D000951:Antigens, Neoplasm / Q000276:immunology*; D001943:Breast Neoplasms / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005260:Female; D006801:Humans; D015151:Immunoblotting; D008969:Molecular Sequence Data; D009077:Mucins / Q000276:immunology*; D010051:Ovarian Neoplasms / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology*; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000939:Epitopes; D009077:Mucins; D010446:Peptide Fragments; C017589:ovarian tumor associated antigen; C065498:peptide p(1-24)