SERPINB1/SERPINB9 protein level ratio in blood (Ontology of Biological Attributes identifier OBA_2055754) can be described as follows. A compound attribute that is the ratio of amount of leukocyte elastase inhibitor (human) in blood to amount of serpin B9 (human) in blood. Also known as: the ratio of amount of leukocyte elastase inhibitor (human) in blood to amount of serpin B9 (human) in blood.