earticle

영어

Previously, we showed that simple paucimannosidic N-glycan structures in insect Drosophila S2 cells arise mainly because of β-N-acetylglucosaminidase (GlcNAcase) action, which removes terminal N-acetylglucosamine (GlcNAc) residues. In an earlier report, we suppressed GlcNAcase activity and clearly demonstrated that more complex N-glycanswithtwo terminal GlcNAc residues were synthesized. In the present work, we investigated synergistic effects of N-acetylglucosaminyltransferase II and/or β -1,4-galactosyltransferase co-expressions (by recombinant baculoviral infection) and GlcNAcase suppression (by knock-out screening) on N-glycan patterns. Using HPLC and MALDI-TOF MS analyses, we found that the N-glycosylation pattern of human erythropoietin secreted by engineered S2 cells expressing glycosyltransferase but not GlcNAcase was complete except for sialylation; N-glycan structures had two terminal galactose residues. Therefore, it will be possible to express complete functional human therapeutic glycoprotein in engineered Drosophila cells by suppressing GlcNAcase and co-expressing additional glycosyltransferases of N-glycosylation pathway.