Lysosomal Enzymes in Human Peripheral Blood Mononuclear Cells and Granulocytes (Technical Briefs‪)‬

Lysosomal enzymes are crucial for the degradation of numerous macromolecular substrates. Deficiencies of many of the known lysosomal enzyme activities have been associated with different clinical disorders, collectively termed the lysosomal storage diseases (1-4). Accurate measurement of lysosomal enzyme activities, therefore, is important in establishing diagnoses of lysosomal storage diseases. In addition, accurate measurement of these lysosomal enzymes is critical in identifying carriers or heterozygotes for these conditions and in monitoring patients with these diseases who have undergone bone marrow transplantation and other enzyme replacement therapies. Clinical laboratories that measure lysosomal enzyme activities typically use sonicates or detergent extracts of mixed leukocyte pellets for enzymologic studies of lysosomal disorders. The use of peripheral blood leukocytes for this purpose has the merit of using a readily accessible tissue that, in addition, has considerable concentrations of most lysosomal enzymes.