A compound attribute that is the ratio of amount of CD166 antigen (human) in blood to amount of Kunitz-type protease inhibitor 1 (human) in blood. The trait is ALCAM/SPINT1 protein level ratio in blood (OBA_2054299, an Ontology of Biological Attributes entry). Also known as: the ratio of amount of CD166 antigen (human) in blood to amount of Kunitz-type protease inhibitor 1 (human) in blood.