Glycoproteins antigenic determinants

CA 125 is a mucin-like glycoprotein antigenic determinant expressed on the surface of coelomic epithelium and human ovarian carcinoma cells however, it does not appear to be specific for ovarian cancer because elevated levels have been reported in breast and colorectal cancers. Studies have shown increased CA 125 levels in patients with ovarian cancer, whereas decreased CA 125 levels in chemotherapy are associated with improved possibility for survival. Some studies have shown failure of CA 125 levels to return to normal after chemotherapy, indicating... 

Urinary casts, often excreted by patients having renal disease, possess414 antigenic determinants in common with the Tamm-Horsfall protein (see p. 414), and, indeed, this glycoprotein is the major component of the casts.414-416 However, the reason for its aggregation is as yet unknown. Other pathological states may well be found to be associated with abnormalities in the structure or metabolism, or both, of glycoproteins. 

The presence of one antigenic determinant may reduce the extent of expression of another. Thus, in an A glycoprotein of a secretor, the expression of the H determinant is largely inhibited, and by using enzymes (30) which destroy A or B activity, H activity is greatly increased (3, 7). Also, gene interactions may occur as, for example, when the H and Le genes are both present, a new specificity termed Leb arises... 

The existence of several different antigenic determinants on the surface of macromolecules such as proteins and on complex glycoproteins such as the water-soluble blood group glycoproteins these often are found in more than a single copy per molecule. Antibodies may be formed to the various antigenic determi-... 

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