HBEGF/PLXNA4 protein level ratio in blood (OBA_2053005) can be described as follows. A compound attribute that is the ratio of amount of proheparin-binding EGF-like growth factor (human) in blood to amount of plexin-A4 (human) in blood. Also known as: the ratio of amount of proheparin-binding EGF-like growth factor (human) in blood to amount of plexin-A4 (human) in blood.