On the surface of endothelial cells (ECs) lies the glycocalyx, a barrier of polysaccharides that isolates the ECs from the blood. The role of the glycocalyx is dynamic and complex, thanks to not only its structure, but its vast number of components, one being hyaluronan (HA). HA is a critical component of the glycocalyx, having been found to have a wide variety of functions depending on its molecular weight, its modification, and receptor–ligand interactions. As HA and viscous blood are in constant contact, HA can transmit mechanosensory information directly to the cytoskeleton of the ECs. The degradation and synthesis of HA directly alters the permeability of the EC barrier; HA modulation not only alters the physical barrier but also can signal the initiation of other pathways. EC proliferation and angiogenesis are in part regulated by HA fragmentation, HA-dependent receptor binding, and downstream signals. The interaction between the CD44 receptor and HA is a driving force behind leukocyte recruitment, but each class of leukocyte still interacts with HA in unique ways during inflammation. HA regulates a diverse repertoire of EC functions.

内皮细胞 (EC) 的表面存在糖萼，这是一种将 EC 与血液隔离的多糖屏障。糖萼的作用是动态且复杂的，这不仅归功于其结构，还归功于其大量的成分，透明质酸 (HA) 就是其中之一。HA 是糖萼的重要组成部分，已被发现具有多种功能，具体取决于其分子量、修饰和受体-配体相互作用。由于HA和粘性血液不断接触，HA可以将机械感觉信息直接传递到EC的细胞骨架。HA的降解和合成直接改变EC屏障的通透性；HA 调节不仅可以改变物理屏障，还可以发出其他途径启动的信号。EC 增殖和血管生成部分受到 HA 碎片、HA 依赖性受体结合和下游信号的调节。CD44 受体和 HA 之间的相互作用是白细胞募集的驱动力，但在炎症过程中，各类白细胞仍然以独特的方式与 HA 相互作用。HA 调节 EC 的多种功能。