Thomsen–Friedenreich antigen

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Thomsen–Friedenreich antigen (Galβ1-3GalNAcα1) is a disaccharide. [1] It is usually present on cell surfaces in a cryptic form covered by [2] N-Acetylneuraminic acid moieties, and is released into circulation in many different cancers.[ citation needed ]



The Thomsen–Friedenreich antigen (Gal-GalNAc) represents a tumor-associated molecule, which is assumed to be one of the few chemically well-defined antigens with a proven association with malignancy. In order to analyze the role of the carbohydrate structure Gal-GalNAc for gastrointestinal tumors, Balb/c mice with MCF-7 breast tumor cells were immunized, together with synthetic Gal-GalNAc linked to a BSA carrier. One monoclonal antibody (82-A6) was established that recognizes the Thomsen–Friedenreich antigen according to the biochemical and serological analysis presented here.

In contrast to studies performed in the past, immunohistochemical results using the antibody 82-A6 did not exhibit a reactivity clearly restricted to tumors. Preliminary biochemical analysis revealed that the T-determinant is detectable in the high-molecular weight range (about 1000 kD), suggesting that the Gal-GalNAc epitope is found on mucin-like glycoproteins. Tumor restriction of the Thomsen–Friedenreich antigen may therefore be determined either by the protein backbone or by the beta-glycosidic linkage of the carbohydrate structure to the protein.

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Immune system A biological system that protects an organism against disease

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  1. Yu, Lu-Gang (2007). "The oncofetal Thomsen–Friedenreich carbohydrate antigen in cancer progression". Glycoconjugate Journal. 24 (8): 411–20. doi:10.1007/s10719-007-9034-3. PMID   17457671.