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

Authors

One Choi, Johns Hopkins University
Noboru Tomiya, Johns Hopkins University
Jung H. Kim, Korea Advanced Institute of Science and Technology
James M. Slavicek, USDA Forest Service
Michael J. Betenbaugh, Johns Hopkins University
Yuan C. Lee, Johns Hopkins University

Document Type

Article

Date of this Version

2003

Comments

Published in Glycobiology vol. 13 no. 7 pp. 539-548, 2003

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 Man1±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)-fucosy- lation 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.