Ruthenium-red-induced cell agglutination and surface glycoprotein and mucopolysaccharide.

Ruthenium red induces the agglutination of ascites hepatoma cells. The agglutination was inhibited by acidic polysaccharides but not by haptenic inhibitors of some plant agglutinins. The agglutination was also abolished by treatment of the cells with a low concentration of papain. Papain digestion causes a decrease in the number of microvilli on the cell surface and the release of carbohydrate-containing materials into the suspending medium. The ' papainate' has more than 2 kinds of ruthenium red-binding substance. One of them is a heparan sulphatelike mucopolysaccharide and the other is a glycoprotein which contains sialic acid. The ruthenium red-binding fractions inhibit the cell agglutination induced by ruthenium red.