title: Mass spectrometric study of N-glycans from serum of woodchucks with liver cancer.
abstract: Woodchucks have been a preferred lab animal model of chronic hepatitis B viral infection. The model recapitulates the disease progression of HBV infection to hepatocellular carcinoma (HCC) and has documented similarities in protein glycosylation with human HCC. This study examined N-glycans in serum of animals with(out) HCC. Oligosaccharides were released enzymatically using PNGaseF from total serum or from serum partially fractionated by extraction. Two different extraction procedures - reversed-phase high-performance liquid chromatography (RP-HPLC) and solid-phase extraction (SPE) on a cation-exchange/reversed-phase STRATA-XC cartridge - were used with the purpose of confirming glycosylation profiles. Oligosaccharides were analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) after derivatization with phenylhydrazine and/or permethylation. Characteristic fragment ions produced under MS/MS conditions allowed discrimination between isomeric structures of oligosaccharides, including those sialylated with two types of acidic residues. The complementary methods allowed structural characterization of oligosaccharides from various N-glycan classes. Furthermore, to validate results, glycosylation profiles of woodchuck sera were compared to glycans obtained from mouse serum on the same conditions. In summary, we have identified 40 N-glycan structures in the serum of woodchucks and some types of oligosaccharide structures appeared to increase in HCC samples following protease digest. The study provides improved tools for the characterization of N-glycans from total serum in the progression of liver disease.
authors.affiliation: Chemistry Department, University of Manitoba, Winnipeg, MB, Canada R3T 2N2. lattovae@cc.umanitoba.ca
authors.forename: Erika
authors.initials: E
authors.lastname: Lattová
authors.forename: Eilean J
authors.initials: EJ
authors.lastname: McKenzie
authors.forename: Marco L H
authors.initials: ML
authors.lastname: Gruwel
authors.forename: Vic
authors.initials: V
authors.lastname: Spicer
authors.forename: Radoslav
authors.initials: R
authors.lastname: Goldman
authors.forename: Hélène
authors.initials: H
authors.lastname: Perreault
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006801:Humans; D007536:Isomerism; D008113:Liver Neoplasms / Q000097:blood*; D008392:Marmota; D051379:Mice; D009844:Oligosaccharides / Q000097:blood / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D009844:Oligosaccharides