level of leucine-rich repeat and fibronectin type-III domain-containing protein 4 in blood serum (OBA_2044328, an Ontology of Biological Attributes identifier) is the amount of a leucine-rich repeat and fibronectin type-III domain-containing protein 4 when measured in blood serum. Also known as: blood serum leucine-rich repeat and fibronectin type-III domain-containing protein 4 amount.