Human Glutathione S-Transferase ELISA Kit
Human Glutathione S-Transferase ELISA Kit is designed to quantitatively measure the activity of GST. A GST standard is provided to generate a standard curve for the assay. The kit utilizes a non-fluorescent molecule that is a substrate for the GST enzyme which covalently attaches to glutathione (GSH) to yield a highly fluorescent product. In the end point mode, mixing the sample or standard with the supplied Detection Reagent and GSH yields a fluorescent product which is read at 460nm in a fluorescent plate reader with excitation at 390nm. For rate determination, the intensity at 460nm is read periodically and plotted versus time.
The Glutathione S-Transferase (GST) family of isozymes function to detoxify and neutralize a wide variety of electrophilic molecules by mediating their conjugation with reduced glutathione. Human GSTs are encoded by 5 gene families, expressing in almost all tissues as four cytosolic and one microsomal forms. Dividing the family by isoelectric points, the basic alpha (pI 8 to 11), the neutral mu (pI 5 to 7) and acidic pi (pH<5) classes are populated by additional subclasses, each isozyme displaying differential specificity for given electrophilic molecules. Given its pivotal role in ameliorating oxidative stress/damage, GST activity has been repeatedly investigated as a biomarker for arthritis, asthma, COPD, and multiple forms of cancer, as well as an environmental marker. Examination of GST isoforms and activity in human cancers, tumors and tumor cell lines has revealed the predominance of the acidic pi class. Furthermore, this activity is thought to substantially contribute to the innate or acquired resistance of specific neoplasms to anticancer therapy.