Pre-Albumin ELISA

Prealbumin (transthyretin) is a transport protein secreted in the liver, brain and retina. It transports thyroxin (T4 ) and retinol binding protein in serum and cerebrospinal fluid. Its names are derived from its function (transports thyroxin and retinol) and the fact that it runs in front of albumin (prealbumin) in electrophoresis gels. Prealbumin (transthyretin) is a 55kDa homotetramer with a dimer of dimers quaternary structure. Each monomer is a 127-residue polypeptide rich in beta sheets. Association of two monomers forms a dimer, two dimers produce the homotetrameric structure and create the two thyroxine binding sites per tetramer. Transthyretin is reduced in inflammatory reactions and is therefor an acute-phase protein. A mutation in the transthyretin gene can result in a chronically lowered transthyretin level in the blood, leading to amyloidosis. Transthyretin is the protein with the highest proportion of essential amino acids and has a rather short biological halflife of 1–2 days.