N-glycan structures of human transferrin produced by Lymantria dispar (gypsy moth)cells using the LdMNPV expression system

Abstract

N-glycan structures of recombinant human serum transferrin (hTf) expressed by Lymantria dispar (gypsy moth) 652Y cells were determined. The gene encoding hTf was incorporated into a Lymantria dispar nucleopolyhedrovirus (LdMNPV) under the control of the polyhedrin promoter. This virus was then used to infect Ld652Y cells, and the recombinant protein was harvested at 120 h postinfection. N-glycans were released from the purified recombinant human serum transferrin and derivatized with 2-aminopyridine; the glycan structures were analyzed by a two-dimensional HPLC and MALDI-TOF MS. Structures of 11 glycans (88.8% of total N-glycans) were elucidated. The glycan analysis revealed that the most abundant glycans were Man_1-3(±Fucα6)GlcNAc₂ (75.5%) and GlcNAcMan₃(±Fucα6)GlcNAc₂ (7.4%). There was only ~6% of high-mannose type glycans identified. Nearly half (49.8%) of the total N-glycans contained α(1,6)-fucosylation on the Asn-linked GlcNAc residue. However α(1,3)-fucosylation on the same GlcNAc, often found in N-glycans produced by other insects and insect cells, was not detected. Inclusion of fetal bovine serum in culture media had little effect on the N-glycan structures of the recombinant human serum transferrin obtained.

Citation

Choi, One; Tomiya, Noboru; Kim, Jung H.; Slavicek, James M.; Betenbaugh, Michael J.; Lee, Yuan C. 2003. N-glycan structures of human transferrin produced by Lymantria dispar (gypsy moth)cells using the LdMNPV expression system. Glycobiology 13(7):539-548