Advances of hyaluronic acid in stem cell therapy and tissue engineering, including current clinical trials.

Hyaluronic acid (HA), as one of the main components of the extracellular matrix (ECM), plays a significant role in a multitude of biological processes involving cell migration, proliferation, differentiation, wound healing and inflammation. Thanks to its excellent biocompatibility, biodegradability and hygroscopic properties, HA has been used in its natural form for joint lubrication and ocular treatment. The chemical structure of HA can be easily modified by direct reaction with its carboxyl and hydroxyl groups.