The Determination of Human Urinary [gamma]-Esterase Activity using Antibody-Conjugated Paper Disk

A new and specific method for the determination of human urinary γ-esterase activity, which migrates to the γ-globulin region on cellulose acetate electrophoresis, was developed using an antibody-conjugated paper disk. The method was applied experimentally, and the results indicate that an increase of γ-esterase activity in the urine reflects renal damage, that is, urinary γ-esterase activity was increased in patients with nephrotic syndrome (20.3±15.0 units/g of creatinine) and chronic nephritis (8.00±5.23 units/g of creatinine) as compared with that of healthy subjects (3.08±1.90 units/g of creatinine). γ-Esterase was localized at the renal tubules of a patient with renal disease, and it was considered that γ-esterase was excreted in the urine when the renal tubules were damaged. Therefore, the determination of urinary γ-esterase activity by this method should be an effective aid in the diagnosis of renal disease.