Objective: To study the glucocerebrosidase (GCase) activity and translocation to lysosomes in cultured macrophages derived from patient blood monocytic cells (PBMC) of Parkinson’s disease patients with GBA mutations (GBA-PD) and asymptomatic carriers of GBA mutations (asymp – GBA).
Background: The GBA gene encodes the lysosomal enzyme GCase, which hydrolyzes glucosylceramide and glucosylsphingosine. Mutations in GBA alters GCase transport to lysosomes and leads to Gaucher disease development. GBA variants are among the most common genetic risk factors for Parkinson’s disease (PD). However, not all carriers of the GBA mutation develop PD during their lifetime. It remains unknown if GCase transport is impaired in GBA –PD patients.
Method: Mononuclear fraction was isolated from whole blood of GBA-PD (N=11), asymp – GBA (N=14) and idiopathic PD patients (iPD, N=13) and healthy controls (N=25). With subsequent differentiated into macrophages using RPMI-1640 supplemented with 10% FBS, 1% streptomycin-penicillin and 10 ng/ml M-CSF for 4 days, with daily media changes. GCase enzymatic activity was measured by liquid chromatography with tandem-mass spectrometry (LC-MS/MS) in dry macrophage cell spots on filter paper with the concentration of 2×10^6 cells/ml. The translocation of GCase (Alexa Fluor 488) to lysosomes (marker LAMP2 (Cy3)) was demonstrated in PBMC-derived macrophages. Images were acquired using a Leica TCS-SP5 confocal microscope (×63 magnification).
Results: In our study, we showed differences in GCase activity in PBMC-derived macrophages from GBA-PD, asymp – GBA, iPD patients and controls (Table 1).
[table1]
A decreased translocation of GCase to lysosomes, by decreased colocalization of GCase with the lysosomal marker LAMP2 was observed in PBMC-derived macrophages from GBA-PD and asymp – GBA patients compared to controls (Fig. 1 A-B).
[figure1]
Conclusion: In PBMC-derived macrophages from asymp – GBA and iPD patients have decreased GCase activity compared to controls. Although there is a question why GCase activity in PBMC-derived macrophages from GBA-PD patients has no difference compared to controls. Patients with GBA mutations characterized by impaired GCase transport to lysosomes.
The study was supported by RSF № 19-15-00315
To cite this abstract in AMA style:
A. Kopytova, M. Nikolaev, K. Senkevich, D. Bogdanova, A. Izymchenko, G. Baydakova, I. Miliukhina, E. Zakharova, S. Pchelina. Impaired glucocerebrosidase transport to lysosomes in cultured macrophages derived from blood monocytic cells of patients with Parkinson’s disease associated with mutations in the GBA gene [abstract]. Mov Disord. 2021; 36 (suppl 1). https://www.mdsabstracts.org/abstract/impaired-glucocerebrosidase-transport-to-lysosomes-in-cultured-macrophages-derived-from-blood-monocytic-cells-of-patients-with-parkinsons-disease-associated-with-mutations-in-the-gba-gene/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2021
MDS Abstracts - https://www.mdsabstracts.org/abstract/impaired-glucocerebrosidase-transport-to-lysosomes-in-cultured-macrophages-derived-from-blood-monocytic-cells-of-patients-with-parkinsons-disease-associated-with-mutations-in-the-gba-gene/