Placental Alkaline Phosphatase (PLAP) is a membrane-bound glycoprotein enzyme that plays a crucial role in various physiological processes. It is encoded by the ALPP gene and is part of a multigene family that includes at least three other isozymes: intestinal, placental-like, and liver/bone/kidney alkaline phosphatases . The enzyme is involved in dephosphorylation reactions, which are essential for the regulation of many biological processes, including signal transduction, energy metabolism, and molecular transport.
PLAP is predominantly expressed in the placenta during the third trimester of gestation . It is also found in other tissues such as the endocervix and fallopian tube, and in certain types of tumors, including ovarian and proximal gastrointestinal tumors . The expression of PLAP is regulated by various factors, including hormonal changes during pregnancy.
PLAP has significant clinical implications, particularly in the diagnosis and monitoring of certain diseases. It is used as a tumor marker for testicular germ cell tumors and other malignancies . Elevated levels of PLAP can indicate the presence of these tumors, making it a valuable tool in oncology.
Additionally, PLAP has been linked to hypophosphatasia, a rare genetic disorder characterized by defective bone mineralization and a range of skeletal abnormalities . The severity of hypophosphatasia can vary depending on the specific mutation in the ALPP gene.
Recombinant human PLAP is produced using advanced biotechnological methods, typically involving the expression of the ALPP gene in host cells such as HEK 293 cells . This recombinant form of PLAP is used in various research applications, including enzyme assays, structural studies, and the development of diagnostic tools.
Recombinant PLAP is characterized by its high purity and specific activity, making it suitable for a wide range of experimental applications . It is often tagged with a His-tag to facilitate purification and detection in laboratory settings.
Recombinant PLAP is widely used in biomedical research to study its structure, function, and role in disease processes. It is also employed in the development of diagnostic assays for detecting PLAP levels in clinical samples . The availability of recombinant PLAP has significantly advanced our understanding of this enzyme and its implications in health and disease.