Process and Tools for Making Heparin Sulfate Proteoglycans and Fusion Proteins
Inventors: Merton Bernfield, Scott Saunders
Invention Types: Therapeutics
Research Areas: Metabolic Disease, Surgery/Wound Healing, Audiology, Infectious Disease
Keywords: For More Information Contact: Yen, Alan
Heparan sulfate chains added as post-translational modifications give certain proteins a unique ability to bind with high specficity to other macromolecules including growth factors, cell adhesive molecules, viral and parasitic pathogens as well as enzymes,and an ability to stabilize and or modify the activity of these ligands. This invention uses the heparan sulfate attachment region of syndecan-1 to genetically engineer heparan sulfate moieties onto other proteins. A small region of cDNA, encoding a region of syndecan sufficient for attachment and synthesis of a heparan sulfate chain, is ligated with a cDNA encoding the protein of interest, transfected into eukaryotic cells, resulting in the production of a new macromolecule, containing a heparan sulfate chain. This chimeric molecule would have new biological properties conferred by the presence of the heparan sulfate chains. The heparan sulfate chain attachment and synthesis region (HS-ASR) of syndecan could be covalently cross-linked to various other organic and non organic molecules such as pharmaceuticals, prosthetic devices, etc, after expression by itself and purification. Furthermore the construction of chimeras including HS-ASR's from different syndecans might produce products with distinct activities.|
The invention would have potential utility in at least the following areas:|
1) Growth Factors - Production of chimeric moleculs with heparin binding growth factors would result in growth factors with improved stability, activity and possibly new activities.
2) Anti-infective Agents - Viral and parasitic pathogens that utilize cell surface heparan surface as binding sites might be blocked by cell-type-specfic heparan sulfate. Furthermore, these heparan sulfate containing molecules can be covalently linked to anti-infective drugs, thus improving their delivery specifically to infected cells.
3) Enzyme/Enzyme Inhibitors - Heparin binding enzymes and enzymes inhibitors may be expressed as chimeras containing heparan sulfate chains with constitutively modified activity.
4) Adhesive molecules - chimeras of cell binding proteins could have enhanced properties as pharmaceuticals (wound repair), research reagents (cell culture substrates), and biomaterials (prosthetic devices) due to their ability to both bind cells ans cellular growth factors.
5) Anti-adhesive molecules - Competitive inhibitors of cell binding, made into -dimers- through the addition of these syndecan heparan sulfate chains, could have improved activity as anti-adhesive molecules.|
Much has been published in the research literature about the fact that syndecan molecules serve as co-receptors and docking mechanisms for many growth factors and signaling molecules on the surface of mammalian cells. It is believed that such molecules and/or drugs that affect them can serve as modulators of cell signaling activity.