TSG-6 Protein, Human (His)

The TSG-6 protein is a major regulator of extracellular matrix organization during tissue remodeling. It catalyzes the transfer of a heavy chain from the inter-alpha-inhibitor complex to hyaluronan, facilitating the formation of hyaluronan-HC oligomers and a hyaluronan-rich matrix surrounding the cumulus cell-oocyte complex, which is essential for oocyte fertilization. Additionally, TSG-6 assembles hyaluronan in pericellular matrices that act as platforms for receptor clustering and signaling. It also plays a role in immune response modulation, by altering hyaluronan binding to CD44 on vascular endothelium and facilitating leukocyte rolling. Furthermore, TSG-6 modulates the interaction of chemokines with extracellular matrix components and proteoglycans on endothelial cell surfaces, thereby preventing chemokine gradient formation. It also limits excessive neutrophil recruitment at inflammatory sites by antagonizing the association of CXCL8 with glycosaminoglycans on vascular endothelium. TSG-6 has a role in osteogenesis and bone remodeling as well, inhibiting the differentiation of mesenchymal stem cells to osteoblasts and protecting against bone erosion during inflammation by inhibiting osteoclast activation.