Xue-Long Sun, PhD, FAHA

Dr. Sun’s laboratory is working in Medicinal and Pharmaceutical Chemistry and Chemical Biology area.

We are interested in cell surface and receptors’ glycosylation patterns and changes under pathological pathways. One major research project is developing novel chemical probes and enzyme inhibitors to profile and modulate sialylaion and desialylation of receptor proteins in immune cells, including monocytes and macrophages related to infection, immune response and inflammation. The long-term goal of this research is to discover the sialylation molecular mechanisms in infection, immune response and inflammation and identify novel targets and lead compounds for antiviral infection and anti-inflammation drug development for flu and coronavirus infection and sepsis.

• Yang D, Wu Y, Turan I, Keil J, Li K, Chen MH, Liu R, Wang L, Sun XL, Chen GY. Targeting intracellular Neu1 for Coronavirus Infection Treatment. iScience, 2023, 26, 106037.
• Keil JM, Rafn GR, Turan IM, Aljohani MA, Sahebjam-Atabaki R, Sun XL. Sialidase Inhibitors with Different Mechanisms. J Med Chem (Perspective Review) 2022, 65, 13574-13593.
• Zhao Y, Mahajan G, Kothapalli CR, Sun XL. Sialylation status and mechanical properties of THP-1 macrophages upon LPS stimulation. Biochem Biophys Res Commun. 2019, 518(3):573-578.
• Whited J, Zhang X, Nie H, Wang D, Li Y, Sun XL. Recent Chemical Biology Approaches for Profiling Cell Surface Sialylation Status. ACS Chem Biol. 2018, 13(9):2364-2374.
• Wang D, Ozhegov E, Wang L, Zhou A, Nie H, Li Y, Sun XL. Sialylation and desialylation dynamics of monocytes upon differentiation and polarization to macrophages. Glycoconj J. 2016 Oct;33(5):725-33.

In addition, we are interested in biomimetic synthesis of native biomolecule thrombomodulin (TM) for the compensation of its loss in the pathological site, as an on-demand anticoagulant and anti-inflammatory therapeutic strategy. Specifically, we are developing TM-liposome conjugates that mimic the native endothelial antithrombotic mechanism of both TM and lipid components and thus will provide a more forceful antithrombotic agent. Also, we are developing TM-glycosaminoglycan (GAG) conjugates and investigating the significance of GAG on the antithrombotic activity and pharmacokinetic properties of TM.

• Gruzdys V, Wang L, Wang D, Huang R, Sun XL. Investigation of cofactor activities of endothelial microparticle-thrombomodulin with liposomal surrogate. Biochem Biophys Res Commun. 2023, 651:79-84.
• Boron M, Hauzer-Martin T, Keil J, Sun XL. Circulating Thrombomodulin: Release Mechanisms, Measurements, and Levels in Diseases and Medical Procedures. TH Open. 2022, 6(3):e194-e212.
• Liu X, Boron M, Zhao Y, Sun XL. End-point modification of recombinant thrombomodulin with enhanced stability and anticoagulant activity. Eur J Pharm Sci. 2019, 139, 105066.
• Wang L, Jiang R, Liu Y, Cheng M, Wu Q, Sun XL. Recombinant and chemo-/bio-orthogonal synthesis of liposomal thrombomodulin and its antithrombotic activity. J Biosci Bioeng. 2017, 124(4):445-451.
• Wang L, Jiang R, Wang L, Liu Y, Sun XL. Preparation of chain-end clickable recombinant protein and its bio-orthogonal modification. Bioorg Chem. 2016, 65:159-66.

Furthermore, we are developing biomimetic glycoligands for microarray, carbon nanotube, quantum dot and liposome surface functionalization for biosensor and drug delivery applications. In particular, we are making macro-glycoligands with native glycans in native linkage, in controlled density and orientation for both specificity and affinity.

• DiLillo AM, Chan KK, Sun XL, Ao G. Glycopolymer-Wrapped Carbon Nanotubes Show Distinct Interaction of Carbohydrates with Lectins. Front Chem. 2022, 10:852988.
• Sonia Tomar and Xue-Long Sun*, Carbohydrate Functionalized Liposomes and Applications, Comprehensive Glycoscience, 2nd edition, Editor Joseph J. Barchi, 2021, Page 370-379.
• Bigdelou P, Chan KK, Tang J, Yu KN, Whited J, Wang D, Lee MY, Sun XL. High-throughput multiplex assays with mouse macrophages on pillar plate platforms. Exp Cell Res. 2020, 396, 112243.
• Chan KK, Lei Q, Tang J, Sun XL. Synthesis of aryl azide chain-end functionalized N-linked glycan polymers and their photo-labelling of specific protein. RSC Adv. 2020, 10(63):38561-38565.
• Tang J, Ozhegov E, Liu Y, Wang D, Yao X, Sun XL. Straightforward Synthesis of N-Glycan Polymers from Free Glycans via Cyanoxyl Free Radical-Mediated Polymerization. ACS Macro Lett. 2017, 6(2):107-111.

Our research has been supported by NIH RO1 and R15 grants, AHA research grant, NSF research grant, CSU Startup Fund and Internal Grants. Many Thanks!