Bone sialoprotein (BSP) is a component of mineralized tissues such as bone, dentin, cementum and calcified cartilage. BSP is a significant component of the bone extracellular matrix and has been suggested to constitute approximately 8% of all non-collagenous proteins found in bone and cementum. BSP, a SIBLING protein, was originally isolated from bovine cortical bone as a 23-kDa glycopeptide with high sialic acid content.
The human variant of BSP is called bone sialoprotein 2 also known as cell-binding sialoprotein or integrin-binding sialoprotein and is encoded by the IBSP gene.
