OBA_2055647 (SIGLEC1/TNFRSF21 protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of sialoadhesin (human) in blood to amount of tumor necrosis factor receptor superfamily member 21 (human) in blood. Also known as: the ratio of amount of sialoadhesin (human) in blood to amount of tumor necrosis factor receptor superfamily member 21 (human) in blood.