BMB Rep. 2015; 48(8): 438-444  
Glyco-engineering strategies for the development of therapeutic enzymes with improved efficacy for the treatment of lysosomal storage diseases
Doo-Byoung Oh1,2,*
1Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), 2Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 34141, Korea
Correspondence to: Tel: +82-42-860-4457; Fax: +82-42-879-8494; E-mail:
Received: May 21, 2015; Published online: August 31, 2015.
© Korean Society for Biochemistry and Molecular Biology. All rights reserved.

Lysosomal storage diseases (LSDs) are a group of inherent diseases characterized by massive accumulation of undigested compounds in lysosomes, which is caused by genetic defects resulting in the deficiency of a lysosomal hydrolase. Currently, enzyme replacement therapy has been successfully used for treatment of 7 LSDs with 10 approved therapeutic enzymes whereas new approaches such as pharmacological chaperones and gene therapy still await evaluation in clinical trials. While therapeutic enzymes for Gaucher disease have N-glycans with terminal mannose residues for targeting to macrophages, the others require N-glycans containing mannose-6-phosphates that are recognized by mannose-6-phosphate receptors on the plasma membrane for cellular uptake and targeting to lysosomes. Due to the fact that efficient lysosomal delivery of therapeutic enzymes is essential for the clearance of accumulated compounds, the suitable glycan structure and its high content are key factors for efficient therapeutic efficacy. Therefore, glycan remodeling strategies to improve lysosomal targeting and tissue distribution have been highlighted. This review describes the glycan structures that are important for lysosomal targeting and provides information on recent glyco- engineering technologies for the development of therapeutic enzymes with improved efficacy.
Keywords: Enzyme replacement therapy, Glcyan, Glyco-engineering, Lysosomal storage disease, Mannose-6-phosphate, Therapeutic enzymes

This Article