Specific Determination of -Galactocerebrosidase Activity via Competitive Inhibition of -Galactosidase

BACKGROUND: The determination of cellular -galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell– based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for -galactocerebrosidase show high specificity but generally require large protein amounts from scanty sources such as hematopoietic or neural stem cells. We developed a novel assay based on the hypothesis that specific measurements of -galactocerebrosidase activity can be performed following complete inhibition of -galactosidase activity.