Isolation and preliminary characterization of glycosaminoglycans in human plasma

Plasma glycosaminoglycans were isolated, after pronase digestion by precipitation with cetylpyridinium chloride. The glycosaminoglycans in plasma were found exclusively in the protein fraction precipitated by trichloroacetic acid. The concentration of glycosaminoglycans in normal plasma was 168 to 272 μg per 100 ml.

Electrophoresis of plasma glycosaminoglycans in barium acetate buffer on cellulose acetate revealed three fractions, all resistant to streptomyces hyaluronidase but susceptible to testicular hyaluronidase. Electrophoretic mobility of the major fraction was similar to dermatan sulfate and hyaluronic acid. Enzymatic assay with chondroitinases, however, indicated that the major constituent of plasma glycosaminoglycans was undersulfated chondroitin sulfate composed of equimolar amounts of unsaturated non-sulfated disaccharides and unsaturated 4-sulfated disaccharides at the disaccharide subunit levels.

The other two fractions were identical with chondroitin sulfate A and C. The quantity of chondroitin sulfate C was least. Hyaluronic acid and over-sulfated chondroitin sulfate were not demonstrated in plasma.