Bone chondroadherin promotes attachment of osteoblastic cells to solid-state substrates and shows affinity to collagen

Chondroadherin, which is reported to be synthesized by chondrocytes and to promote their attachment, was purified from bovine bone. It was a minor component of bone organic matrix, and was present in the 4 M guanidine extract of demineralized bone. Chondroadherin promoted attachment of osteoblastic cells to solid-state substrates, and bound to collagen. Binding of chondroadherin to collagen was significantly higher than that of osteonectin or decorin. These findings imply that chondroadherin may play a role in maintaining bone cells on the collagen matrices of bone.