Ontology of Biological Attributes id OBA_2054571 (MMP1/MMP3 protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of interstitial collagenase (human) in blood to amount of stromelysin-1 (human) in blood. Also known as: the ratio of amount of interstitial collagenase (human) in blood to amount of stromelysin-1 (human) in blood.