Ontology of Biological Attributes entry OBA_2053816 (MANF/PDGFB protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of mesencephalic astrocyte-derived neurotrophic factor (human) in blood to amount of platelet-derived growth factor subunit B (human) in blood. Also known as: the ratio of amount of mesencephalic astrocyte-derived neurotrophic factor (human) in blood to amount of platelet-derived growth factor subunit B (human) in blood.