Ontology of Biological Attributes identifier OBA_2054220 (CD40/VSIR protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of tumor necrosis factor receptor superfamily member 5 (human) in blood to amount of V-type immunoglobulin domain-containing suppressor of T-cell activation (human) in blood. Also known as: the ratio of amount of tumor necrosis factor receptor superfamily member 5 (human) in blood to amount of V-type immunoglobulin domain-containing suppressor of T-cell activation (human) in blood.