Description of target: Pregnancy zone protein (PZP) is a protein which in humans is encoded by the PZP gene on chromosome 12. It is mapped to 12p13.31. The protein encoded by this gene is highly expressed in late-pregnancy serum and is similar in structure to alpha-2-macroglobulin. The encoded protein, which acts as a homotetramer, inhibits the activity of all four classes of proteinases. This protein contains cleavage sites for several proteinases. Upon binding of a proteinase, the conformation of this protein changes to trap the proteinase, limiting its activity. This protein appears to be elevated in the sera of presymptomatic Alzheimer's disease patients.;Species reactivity: Human;Application: ELISA;Assay info: ;Sensitivity: <50pg/ml