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fetuin

n. (context protein English) Any of a family of plasma glycoproteins, secreted from the liver into the bloodstream

Wikipedia
Fetuin

Fetuins are blood proteins that are made in the liver and secreted into the bloodstream. They belong to a large group of binding proteins mediating the transport and availability of a wide variety of cargo substances in the bloodstream. The best known representative of these carrier proteins is serum albumin, the most abundant protein in the blood plasma of adult animals. Fetuin is more abundant in fetal blood, hence the name "fetuin" (from Latin, fetus). Fetal calf serum contains more fetuin than albumin, while adult serum contains more albumin than fetuin.