Removal of PAS Positive Surface Sugars in Tumor Cells by Glycosidases.

Abstract

Summary Structural components of the coat of fixed TA3 tumor cells are stained both by the Hale and the PAS procedures. The Hale positive material can be removed by active neuramidase, indicating the presence of neuraminic acid. The PAS positive component is not influenced by lipid extraction or by diastase digestion and is only slightly affected by neuramidase. However, it is strongly affected by an enzyme preparation from Clostridium perfringens, containing a mixture of glycosidases. By specific blocking of individual glycosidases in the incubation medium, it was determined that galactose and acetyl-galactosamine are important components for the PAS positivity of the cell coat. Fucose is of less significance and perhaps less abundant than other PAS positive sugar units. N-acetyl-hexosaminidase from fungi of Genus Chalaropsis was also active against the PAS positive cell coat but differed from the glycosidases of CI. perfringens in that it did not require the previous removal of the Hale positive component and was not blocked by N-acetyl-galactosamine, galactose, and fucose.