Human Chorionic Gonadotropin (HCG) is a glycoprotein, which is secreted in large quantities by normal trophoblasts. It is present only in trace amounts in non-pregnant urine and sera but rises sharply during pregnancy. HCG is composed of two non-identical, non-covalently linked polypeptide chains designated as the a- and b-subunits. The a-subunit of HCG is nearly identical to that of thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), and luteinizing hormone (LH). A germ cell tumor which is positive for cytokeratin, placental alkaline phosphatase (PLAP), and HCG but negative for EMA and AFP is probably a choriocarcinoma. Applications: Suitable for use in ELISA. Other applications have not been tested. Recommended Dilutions: Optimal dilutions to be determined by researcher. Recommeded Pair: Capture: C5069-54 or C5069-60 Detection: C5069-66A Affinity Constant: 2.1x10e11L/mole Storage and Stability: May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.