Hyaluronan - magic glue for the regulation of the immune response?

The extracellular matrix-filling material hyaluronan (HA) can modulate the function of antigen-presenting cells, such as dendritic cells (DCs) and macrophages. Recent studies show that DCs are actively involved in this process by expressing HA synthesizing and degrading enzymes. T cells also express these enzymes and require HA to bind to their surface in order to become activated.