Development and application to clinical practice of a validated HPLC method for the analysis of β-glucocerebrosidase in Gaucher disease.

The main objective of our study is to develop a simple, fast and reliable method for measuring β-glucocerebrosidase activity in Gaucher patients leukocytes in clinical practice. This measurement may be a useful marker to drive dose selection and early clinical decision making of enzyme replacement therapy. We measure the enzyme activity by high-performance liquid chromatography with ultraviolet detection and 4-nitrophenyl-β-d-glucopyranoside as substrate. A cohort of eight Gaucher patients treated with enzyme replacement therapy and ten healthy controls were tested; median enzyme activity values was 20.57mU/ml (interquartile range 19.92-21.53mU/ml) in patients and mean was 24.73mU/ml (24.12-25.34mU/ml) in the reference group, which allowed the establishment of the normal range of β-glucocerebrosidase activity. The proposed method for leukocytes glucocerebrosidase activity measuring is fast, easy to use, inexpensive and reliable. Furthermore, significant differences between both populations were observed (p=0.008). This suggests that discerning between patients and healthy individuals and providing an approach to enzyme dosage optimization is feasible. This method could be considered as a decision support tool for clinical monitoring. Our study is a first approach to in depth analysis of enzyme replacement therapy and optimization of dosing therapies.