Endothelial Glycocalyx: From Microscope Stage to Bedside

BACKGROUND: It sounds paradoxical that a tiny component of the cellular mantle known as glycocalyx is also the most ubiquitous, more so than mitochondria or nuclei, endowing glycocalyx coverage to every cell with no exceptions. Despite a relatively short history, this organelle has received exponentially growing attention and number of publications as reflected in the last decade. This cellular mantle consists of 4 transmembrane proteins and 6 GPI-anchored proteins, all of which are decorated with glycosaminoglycans like heparan, chondroitin and dermatan sulfates, and hyaluronic acid. All this has been exhaustively reviewed. SUMMARY: Our goal here will be to briefly sketch the important common features of glycocalyx, especially of endothelial cells, and to focus on clinically pertinent practical aspects of this structure. We will describe visual and biochemical detection challenges, highlight the usefulness of identifying and quantifying glycocalyx fragments in biological fluids while broadening the spectrum of specimens for diagnostic purposes, and discuss how these parameters may provide valuable clues regarding their therapeutic relevance as pharmacological targets. KEY MESSAGE: The glycocalyx represents a clinically valuable target and advances in its detection can enhance diagnostic precision and strengthen its translational relevance.