C4BPB/ENTPD5 protein level ratio in blood (Ontology of Biological Attributes entry OBA_2055714) can be described as follows. A compound attribute that is the ratio of amount of C4b-binding protein beta chain (human) in blood to amount of nucleoside diphosphate phosphatase ENTPD5 (human) in blood. Also known as: the ratio of amount of C4b-binding protein beta chain (human) in blood to amount of nucleoside diphosphate phosphatase ENTPD5 (human) in blood.