Human Pappalysin-1/PAPP-A OneStep ELISA Kit

Human Pappalysin-1, commonly known as PAPP-A, is a large zinc-binding metalloproteinase primarily secreted by the placenta during pregnancy, but also expressed in various non-gestational tissues. This protein functions as a key regulator of insulin-like growth factor (IGF) bioavailability. Specifically, PAPP-A cleaves insulin-like growth factor binding proteins (IGFBPs), particularly IGFBP-4 and -5, thereby releasing active IGF-1 from its inactive complexes. This proteolytic activity promotes local IGF signaling, which plays crucial roles in cell proliferation, differentiation, and survival. In clinical practice, PAPP-A is best known as a first-trimester maternal serum biomarker for prenatal screening of fetal aneuploidies, such as Down syndrome (trisomy 21), where altered levels are observed. Beyond pregnancy, PAPP-A is also implicated in various physiological and pathological processes, including wound healing, bone remodeling, and the progression of atherosclerosis and certain cancers. Its ability to modulate the IGF axis positions PAPP-A as an important molecule in both developmental biology and disease pathogenesis.