It is found that the detection of GST subclass levels in biological fluids would be of significant use in monitoring the integrity of specific hepatic regions in the liver. Since αGST has been found to be equally distributed in both the centrilobular and periportal regions of the liver, αGST would be a more sensitive indicator of hepatic status in a variety of clinical conditions including Allograft Rejection, Viral Hepatitis, Chronic Active Hepatitis, and Hepatotoxicity. The FastPack® IP αGST Immunoassay is for the in-vitro quantitative determination of αGST in human serum and plasma. Measurement of αGST can be used as an aid in the assessment of liver damage. The FastPack® IP αGST Immunoassay is designed for use with the FastPack® IP System.