Specificity of human anti-carbohydrate IgG antibodies as probed with polyacrylamide-based glycoconjugates
- 60 Downloads
The TF, Tn, and SiaTn glycotopes are frequently expressed in cancer-associated mucins. Antibodies to these glycotopes were found in human serum. A set of polyacrylamide (PAA)—based glycoconjugates was applied to the direct and competitive enzyme-linked immunosorbent assays (ELISA) to characterize the specificity of serum IgG antibodies. The anti-TF, -Tn and -SiaTn IgG were affinity purified from serum of cancer patients and characterized using PAA-conjugates and free saccharides. The anti-TF and -Tn antibodies were shown to be specific. The anti-TF IgG bound both Galβ1-3GalNAcα- and Galβ1-3GalNAcβ-PAA, the latter was three-four times more effective inhibitor of antibody binding. The anti-Tn IgG reacted only with GalNAcα-PAA. The anti-SiaTn IgG cross-reacted with Tn-PAA but SiaTn-PAA was five-six times more effective inhibitor in a competitive assay. The IC50 values for PAA-conjugates with the corresponding antibodies typically ranged from 2 to 5 × 10−8 M. The antibodies display a low specificity to mucin-type glycoconjugates in comparison with PAA-conjugates as was shown for mucins isolated from human malignant tumor tissues, ovine submaxillary mucin (OSM) and asialo-OSM. The unusual IgG-antibody specificity to GalNAcβ and GalNAcβ1-3GalNAcβ ligands was found in human serum. Published in 2004.
Unable to display preview. Download preview PDF.
- 2.Springer GF, Tegtmeyer H, Origin of anti-Thomsen-Friedenreich (T) and Tn agglutinins in man and in white Leghorn chicks, Br J Haemat 47, 453-60 (1981).Google Scholar
- 9.Smorodin EP, Jansson B, Milyukhina L, Paaski G, Bovin NV, Ovchinnikova TV, Kurtenkov O, Enzyme-linked immunosorbent assay of IgM antibodies to Thomsen-Friedenreich (TF) hapten in oncodiagnostics: comparison of data obtained with four TFglycoconjugates, Russian J Bioorg Chem 23, 718-21 (1997).Google Scholar
- 10.Smorodin JP, Kurtenkov OA, Miljukhina LM, Sergeyev BL, Hint EK, Bovin NV, Lipping AA, Chuzhmarov VJ, Thomsen-Friedenreich antigen-specific IgM antibodies: diagnostic significance for gastric and breast cancer, Exp Oncol 19, 338-42 (1997).Google Scholar
- 11.Smorodin EP, Kurtenkov OA, Sergeyev BL, Lilleorg AL, Chuzmarov VI, Antibodies to tumor-associated carbohydrate epitopes in sera of cancer patients and blood donors, Exp Oncol 23, 109-13 (2001).Google Scholar
- 14.Smorodin EP, Kurtenkov OA, Sergeyev BL, The application of human natural polyclonal IgG-antibodies to Thomsen-Friedenreich epitope (TFE) for evaluation of TFE-expression in cancerassociated mucins, Exp Oncol 22, 44-7 (2000).Google Scholar