Glycocalyx on the surface of endothelial cells, illustration. The glycocalyx (orange) is the glycolipid and glycoprotein layer, consisting of fine filaments, found on the surface of some bacteria, epithelial cells, and other cells. It has functions in cell-to-cell recognition, communication, and adhesion. It has a net-negative charge and can repel other negatively-charged molecules. This includes red blood cells (red) which are repelled from the glycocalyx of vascular endothelial cells.