Multiple forms of gamma-glutamyltransferase: a clinical study

Area of Science:

• Biochemistry
• Clinical Chemistry
• Hepatology

Background:

• Gamma-glutamyltransferase (GGT), leucine aminopeptidase (LAP), and alkaline phosphatase (ALP) are key liver enzymes.
• Altered molecular forms of these enzymes in serum can indicate liver disease.

Purpose of the Study:

• To measure and characterize different molecular forms of GGT, LAP, and ALP in patients with various liver diseases.
• To evaluate the clinical utility of enzyme electrophoresis in diagnosing liver conditions, particularly jaundice.

Main Methods:

• Serum samples from patients with different liver diseases were analyzed.
• Quantification of high- and intermediate-molecular-mass enzyme forms.
• Electrophoretic separation of GGT molecular forms.

Main Results:

• A high-molecular-mass form (>1,000,000 Da) of GGT, LAP, and ALP was elevated in extrahepatic obstructive jaundice.
• Intermediate-molecular-mass GGT (250,000–500,000 Da) showed distinct electrophoretic banding patterns based on liver disease type.
• A specific GGT band predominated in extrahepatic obstructive jaundice.

Conclusions:

• Serum enzyme electrophoresis, particularly for GGT, can aid in distinguishing between extrahepatic and intrahepatic causes of jaundice.
• Molecular forms of liver enzymes provide valuable diagnostic information for liver disease assessment.