LTBR/SIRPB1 protein level ratio in blood (OBA_2055019) can be described as follows. A compound attribute that is the ratio of amount of tumor necrosis factor receptor superfamily member 3 (human) in blood to amount of signal-regulatory protein beta-1 isoforms 1/2 (human) in blood. Also known as: the ratio of amount of tumor necrosis factor receptor superfamily member 3 (human) in blood to amount of signal-regulatory protein beta-1 isoforms 1/2 (human) in blood.