SBIR-STTR Award

The long-term objectives of this proposal are to prepare pure oligosaccharides from glycoproteins possessing asparagine-linked carbohydrate chains and to use the oligosacchardes and their derivatives t investigate the structure, biosynthesis and function of the glycan chains of glycoproteins. The specific aims of this proposal are to purify and characterize high mannose oligosacchardies from soybean proteins. Soybean agglutinin and 7S soybean protein will be purified, their carbohydrate chains released by Endo H and N-glycanase R digestion, and the oligosaccharides isolated after chromatographic separation of the 2-aminopyridyl derivatives. The oligosaccharides will be characterized by hplc analysis, H-NMR spectroscopy, methylation analysis and FAB mass spectroscopy.The purified oligosaccharides will be sold to the research community as part of Genzyme's Glycoprotein Product line. The carbohydrates can be use as standards for structural analysis, as substrates for enzymatic reactions, and as ligands for examining the role of the glycans in the binding of growth factors, hormones, toxins, viruses, bacteria and lectins to cells. One potential large- scale applications for the oligosacchardie is as a ligand to target therapeutic agents to macrophages.National Institute of General Medical Sciences (NIGMS)

The long-term objectives of this project are to identify and characterize cellular receptors for specific oligosaccharides, and to use this information to target therapeutic agents (e.g., proteins) to specific cells. During Phase I, methods to purify high-mannose oligosaccharides were developed. In Phase II, these oligosaccharides will be used for three purposes: (1) preparation of neoglycoproteins for targeting to specific cells, (2) characterization of mannose receptors on immune system cells, and (3) development of new methods for oligosaccharide structural analysis. Technology for purifying individual high-mannose oligosaccharide isomers in quantity will be developed, and methods for coupling these individual oligosaccharides to specific protein amino acids will be explored. Binding of the individual oligosaccharide isomers to the macrophage receptor and to immune system cells will be investigated to determine receptor-binding specificity. The three-dimensional structure of the oligosaccharide isomers will be determined by a combination of NMR and computer modeling studies, and related to the receptor-binding patterns.

Anticipated Results:
The project results will allow optimization of the in vivo efficacy of glucocerebrosidase via targeting to macrophages. This product is currently in Phase II clinical trials for treatment of Gaucher's disease. The project results may also lead to new instrumentation for oligosaccharide analysis.National Institute Of General Medical Sciences (NIGMS)