Interaction of hyaluronectin with hyaluronic acid oligosaccharides

Hyaluronic acid was digested by bovine testicular hyaluronidase, and oligomers were fractionated by gel permeation using AcA 202 Ultrogel, an acrylamide-agarose matrix. Oligosaccharides composed of from two to six disaccharide repeating units were isolated. Two nonasaccharides were prepared by enzymatic or chemical modification of the decasaccharide. Oligosaccharides were compared by a competitive inhibition in the enzyme-linked immunosorbent assay for their ability to inhibit the interaction of hyaluronectin (a hyaluronic acid-binding brain glycoprotein) with hyaluronic acid. Among these oligosaccharides, decasaccharides were the smallest fragments that strongly inhibited the interaction. Octasaccharides inhibited with 700-fold lower affinity than decasaccharides. Dodecasaccharides had the same effect as decasaccharides. Nonasaccharides obtained by beta-glucuronidase splitting of decasaccharides inhibited the interaction more than nonasaccharides prepared by an alkaline treatment.