Production of recombinant human acid α-glucosidase with mannosidic N-glycans in α-mannosidase I mutant rice cell suspension culture

Abstract

High-mannose glycans, containing 6–9 mannose residues, are favorable for in vitro mannose phosphorylation to produce mannose-6-phosphate (M6P) residues, which are essential for uptake into target cells during enzyme replacement therapy of Pompe disease. Golgi α-mannosidase-I mediates mannose trimming in the N-glycosylation pathway. In this study, mutant rice with a T-DNA insertion in the Os04g0606400 (∆α-manI) gene was used to produce recombinant human acid α-glucosidase (rhGAA). Expressed and secreted rhGAA from ∆α-manI (∆α-manI-GAA) in suspension culture media was purified, and analysed by MALDI-TOF. It showed the presence of high-mannose type N-glycans with Man8 (63.8%), Man7 (22.5%), and Man6 (5.4%).