title: Mass spectrometric quantification of neutral and sialylated N-glycans from a recombinant therapeutic glycoprotein produced in the two Chinese hamster ovary cell lines.
abstract: Quality control and assurance of glycan profiles of a recombinant glycoprotein from lot to lot is a critical issue in the pharmaceutical industry. To develop an easy and simple quantitative and qualitative glycan profile method based on matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS), the modification with Girard's reagent T (GT) was exploited. Because GT-derivatized quantification of oligosaccharides using MALDI-TOF MS is possible only with neutral glycans, sialylated glycans are not subjected to quantitative analysis with MALDI-TOF MS. To solve this problem, mild methyl esterification and subsequent GT derivatization were employed, enabling us to perform rapid qualitative and quantitative analysis of sialylated and neutral N-linked oligosaccharides using MALDI-TOF MS. This modified method was used in the comparative quantification of N-glycans from the recombinant therapeutic glycoprotein expressed in two different Chinese hamster ovary (CHO) cell lines. The percentages of sialylated N-glycans to total were 22.5 and 5.2% in CHO-I and CHO-II cells, respectively, resulting in a significant difference in the biological activity of the recombinant glycoprotein.
authors.affiliation: Interdisciplinary Program for Biochemical Engineering and Biotechnology, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Kyoung-Soon
authors.initials: KS
authors.lastname: Jang
authors.forename: Yun-Gon
authors.initials: YG
authors.lastname: Kim
authors.forename: Geun-Cheol
authors.initials: GC
authors.lastname: Gil
authors.forename: Sang-Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Byung-Gee
authors.initials: BG
authors.lastname: Kim
mesh_terms: D000818:Animals; D001622:Betaine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004951:Esterification; D006023:Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D011134:Polysaccharides / Q000032:analysis* / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D006023:Glycoproteins; D011134:Polysaccharides; D011994:Recombinant Proteins; D001622:Betaine; C012332:Girard's reagent T