Cartilage oligomeric matrix protein (COMP) is an abundant component of tendon.

An abundant matrix protein was purified under native conditions from adult bovine tendon and identified as cartilage oligomeric matrix protein (COMP) by immunochemical crossreaction, amino acid sequence identity of tryptic peptides derived from both N- and C-terminal regions, and structure revealed by electron microscopy. Immunohistochemistry showed age-dependent differences in distribution of COMP in tendon.