ANTI-EPITHELIAL MEMBRANE ANTIGEN

Uses

Cell-membrane-associated, mucin-like molecules, such as episialin has a protective function against toxic substances. Data on the effect of episialin on the adhesion properties of cultured cells suggests that episialin expressed at high levels on cells may have a major function in reducing the aggregation capacity of these cells, thus influencing the adherence to various extracellular matrix components by masking adhesion molecules.

General Description

Monoclonal Anti-Episialin (EMA) (mouse IgG1 isotype) is derived from the GP1.4 hybridoma produced by the fusion of mouse myeloma cells and splenocytes from an immunized mouse.

Biochem/physiol Actions

Episialin is a transmembrane, high molecular weight, mucin-like glycoprotein (apparent molecular weight of 265-400 kDa) containing many carbohydrate side chains, that are predominantly attached to the molecule by O-glycosidic linkages. It is known as epithelial membrane antigen (EMA), MUC1 and polymorphic epithelial mucin (PEM). The episialin molecule is transmembranous with a relatively large extracellular domain and a cytoplasmic domain of 69 amino acids. The extracellular domain consists mainly of a region of nearly identical repeats of 20 amino acids, the number of which can vary between about 30 and 90 because of genetic polymorphism. The episialin molecule is synthesized as one large precursor containing only N-linked glycans and is immediately proteolytically cleaved while still in the endoplasmic reticulum.