Pharmacological targeting heparan sulfate–protein interactions
While understanding novel physiological functions of heparan sulfate is always thrilling, finding ways to manipulate its functions in pathological conditions can be life-saving. Heparin, a highly sulfated form of heparan sulfate made by mast cells, has been widely used as a potent anticoagulant for over a century. Heparin works by promoting the inhibition of antithrombin towards thrombin, which drives blood coagulation. We envision that the functions of many more disease-causing HS-binding proteins can be modulated by manipulating their interactions with HS. We believe the interactions can be manipulated in two different ways. The first approach is to utilize structure-defined HS oligosaccharides or HS mimetic, which would function as antagonists or agonists to inhibit or promote the interactions between HS and HS-binding proteins. The second approach is to target the HS-binding sites of HS-binding proteins by mAbs, which would effectively antagonize their interaction with HS and block their function.
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Currently, we are working with Dr. Jian Liu's group to inhibit the activity of HMGB1 using the first approach. We are also developing mAbs to inhibit RAGE activation using the second approach.
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Patents:
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U.S. provisional patent application (No. 62/928,884) was filed on October 31, 2019. The application describes an anti-RAGE mAb that we developed, which inhibits HS-dependent RAGE oligomerization and RAGE signaling. Role: Principle inventor.
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U.S. Provisional Patent Application (No. 62/581,443). The application describes an structure-defined HS oligosaccharides that displays protective effect on drug-induced liver damage. Role: co-inventor (principle inventor: Dr. Jian Liu).
Pharmacological targeting heparan sulfate–protein interactions
While understanding novel physiological functions of heparan sulfate is always thrilling, finding ways to manipulate its functions in pathological conditions can be life-saving. Heparin, a highly sulfated form of heparan sulfate made by mast cells, has been widely used as a potent anticoagulant for over a century. Heparin works by promoting the inhibition of antithrombin towards thrombin, which drives blood coagulation. We envision that the functions of many more disease-causing HS-binding proteins can be modulated by manipulating their interactions with HS. We believe the interactions can be manipulated in two different ways. The first approach is to utilize structure-defined HS oligosaccharides or HS mimetic, which would function as antagonists or agonists to inhibit or promote the interactions between HS and HS-binding proteins. The second approach is to target the HS-binding sites of HS-binding proteins by mAbs, which would effectively antagonize their interaction with HS and block their function.
​
Currently, we are working with Dr. Jian Liu's group to inhibit the activity of HMGB1 using the first approach. We are also developing mAbs to inhibit RAGE activation using the second approach.
​
Patents:
-
U.S. provisional patent application (No. 62/928,884) was filed on October 31, 2019. The application describes an anti-RAGE mAb that we developed, which inhibits HS-dependent RAGE oligomerization and RAGE signaling. Role: Principle inventor.
-
U.S. Provisional Patent Application (No. 62/581,443). The application describes an structure-defined HS oligosaccharides that displays protective effect on drug-induced liver damage. Role: co-inventor (principle inventor: Dr. Jian Liu).
Research Summary
The main interest of Xu lab is to understand how proteins interact with heparan sulfate (HS), a highly negatively charged linear polysaccharide, and the physiological significance of the interactions in bone remodeling and inflammation. Universally expressed by all mammalian cells, HS is a major and often dominant component of the landscape at the cell surface and thus plays essential roles in cell signaling, cell-cell interactions and host-pathogen interactions. At the cell surface and in the extracellular matrix, HS interacts with hundreds of HS-binding proteins, many of which are important drug targets (including receptors, cytokines, chemokines and enzymes). The dependence of these proteins on HS for normal function suggests that disrupting HS-protein interaction could be an effective means to block the activity of these HS-binding proteins.
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Currently we have three main research areas:
Our research is generously supported by: