Glycocalyx Sialic Acid

In current research, the glycocalyx is most often analyzed using fluorescent microscopy techniques with spatial resolution in the range of several hundred nanometers. While this resolution is adequate to quantify the presence or thickness of the glycocalyx, it does not allow for more detailed, qualitative analysis of the structure of individual glycocalyx components.

Previously, Professor Ebong and her colleagues were able to obtain high resolution TEM images of the glycocalyx using a freeze substitution technique, which allowed for proper preservation of the glycocalyx during TEM preparation. We hope to better understand the detailed composition of the glycocalyx through similar TEM techniques as well as from PALM/STORM microscopy, a high resolution fluorescent microscopy technique. Doing so under varying glycocalyx conditions will not only allow us to visualize how the varying proteoglycans and glycoproteins interact, but also help to understand how its structural organization assists in its proper function.

Selected Publications

Cheng, Ming J., et al. Endothelial glycocalyx conditions influence nanoparticle uptake for passive targeting. International Journal of Nanomedicine 11 (2016): 3305. LINK

Tarbell, JOHN M., and E. E. Ebong. Endothelial glycocalyx structure and role in mechanotransduction Hemodynamics and Mechanobiology of Endothelium. Singpore: World Scientific Publishing Co. Pte. Ltd(2010): 69-95.

Ebong, Eno Essien, Sanghee Kim, and Natacha DePaola. Flow regulates intercellular communication in HAEC by assembling functional Cx40 and Cx37 gap junctional channels American Journal of Physiology-Heart and Circulatory Physiology290.5 (2006): H2015-H2023. LINK

Mitra, R., et al., Glycocalyx in Atherosclerosis-Relevant Endothelium Function and as a Therapeutic Target Curr Atheroscler Rep, 2017. 19(12): p. 63.

Ebong, Eno E., et al. Imaging the endothelial glycocalyx in vitro by rapid freezing/freeze substitution transmission electron microscopy Arteriosclerosis, thrombosis, and vascular biology31.8 (2011): 1908-1915. LINK

Thi, Mia M., et al. Interaction of the Glycocalyx with the Actin Cytoskeleton The Cytoskeleton: Imaging, Isolation, and Interaction(2013): 43-62.

Ebong, E. E., et al. Life-like preservation and TEM visualization of the glycocalyx reveals that it is substantial in vitro Bioengineering Conference (NEBEC), 2011 IEEE 37th Annual Northeast. IEEE, 2011. LINK

Ebong, E., et al. Rapid Freezing/Freeze Substitution Transmission Electron Microscopy Assessment of Cultured Endothelial Cell Glycocalyx Structure Microscopy and Microanalysis17 (2011): 162. LINK

Mensah, S.A., et al., Regeneration of glycocalyx by heparan sulfate and sphingosine 1-phosphate restores inter-endothelial communication PLoS One, 2017. 12(10): p. e0186116.

Ebong, Eno E., et al. Shear-induced endothelial NOS activation and remodeling via heparan sulfate, glypican-1, and syndecan-1 Integrative Biology6.3 (2014): 338-347. LINK

Ebong, Eno Essien, David C. Spray, and John M. Tarbell. The Endothelial Glycocalyx In Vitro: Its Structure and The Role of Heparan Sulfate and Glypican-1 in eNOS Activation by Flow. The FASEB Journal24.1_MeetingAbstracts (2010): 784-8.

Ebong, E. E., D. C. Spray, and J. M. Tarbell. The endothelial glycocalyx: Its structure and role in eNOS mechano-activation Bioengineering Conference, Proceedings of the 2010 IEEE 36th Annual Northeast. IEEE, 2010. LINK

Ebong, Eno Essien, David C. Spray, and John M. Tarbell. The Glypican-1 HS Core Protein of the Glycocalyx is Important for Flow-induced Endothelial NOS Activation but not Cell Remodeling. The FASEB Journal25.1_MeetingAbstracts (2011): 39-9.

Zeng, Ye, et al. The structural stability of the endothelial glycocalyx after enzymatic removal of glycosaminoglycans PLoS One7.8 (2012): e43168. LINK