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-acetyl neuraminic acid moieties and released into circulation in many different cancers.[ citation needed ]

Disaccharide complex sugars, the sugar formed when two monosaccharides (simple sugars) are joined by glycosidic linkage; soluble in water; one of the four chemical groupings of carbohydrates

A disaccharide is the sugar formed when two monosaccharides are joined by glycosidic linkage. Like monosaccharides, disaccharides are soluble in water. Three common examples are sucrose, lactose, and maltose.

Moiety (chemistry) (in physical organic chemistry) part of a molecule (the term should not be used for a small fragment of a molecule)

In organic chemistry, a moiety is a part of a molecule which is typically given a name as it can be found within other kinds of molecules as well.

Contents

Abstract

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, we immunized Balb/c mice with MCF-7 breast tumor cells together with synthetic Gal-GalNAc linked to a BSA carrier. One monoclonal antibody (82-A6) was established which recognizes the Thomsen–Friedenreich antigen according to the biochemical and serological analysis presented here. In contrast to the studies performed in the past, immunohistochemical results using this 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 mucinlike glycoproteins. Tumor restriction of 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. As sited on: Dippold, W; Steinborn, A; Meyer; Büschenfelde, KH (August 1990). "The role of the Thomsen-Friedenreich antigen as a tumor-associated molecule". Environ. Health Perspect. 88: 255–7. doi:10.2307/3431086. JSTOR   3431086. PMC   1568008 Lock-green.svg. PMID   2272320. 

Antigen molecule capable of inducing an immune response (to produce an antibody) in the host organism

In immunology, antigens (Ag) are structures specifically bound by antibodies (Ab) or a cell surface version of Ab ~ B cell antigen receptor (BCR). The term antigen originally described a structural molecule that binds specifically to an antibody only in the form of native antigen. It was expanded later to refer to any molecule or a linear molecular fragment after processing the native antigen that can be recognized by T-cell receptor (TCR). BCR and TCR are both highly variable antigen receptors diversified by somatic V(D)J recombination. Both T cells and B cells are cellular components of adaptive immunity. The Ag abbreviation stands for an antibody generator.

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References

  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.
  2. http://pedsccm.org/RARE/HUS.html%5Bunreliable+medical+source?%5D

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