TY - JOUR
T1 - Comparative glycomic profiling of isotopically permethylated N-glycans by liquid chromatography/electrospray ionization mass spectrometry
AU - Hu, Yunli
AU - Desantos-Garcia, Janie L.
AU - Mechref, Yehia
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013/4/30
Y1 - 2013/4/30
N2 - Rationale: Mass spectrometry based comparative glycomics is essential for disease biomarker discovery. However, developing a reliable quantification method is still a challenging task. Methods: We here report an isotopic labeling strategy employing stable isotopic iodomethane for comparative glycomic profiling by liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS). N-Glycans released from model glycoproteins and blood serum samples were permethylated with iodomethane ('light') and iodomethane-d1 or -d3 ('heavy') reagents. Permethylated samples were then mixed at equal volumes prior to LC/ESI-MS analysis. RESULTS Peak intensity ratios of N-glycans isotopically permethylated (Heavy/Light, H/L) were almost equal to the theoretical values. Observed differences were mainly related to the purity of 'heavy' iodomethane reagents (iodomethane-d1 or -d3). The data suggested the efficacy of this strategy to simultaneously quantify N-glycans derived from biological samples representing different cohorts. Accordingly, this strategy is effective in comparing multiple samples in a single LC/ESI-MS analysis. The potential of this strategy for defining glycomic differences in blood serum samples representing different esophageal diseases was explored. Conclusions: LC/ESI-MS comparative glycomic profiling of isotopically permethylated N-glycans derived from biological samples and glycoproteins reliably defined glycan changes associated with biological conditions or glycoproteins expression. As a biological application, this strategy permitted the reliable quantification of glycomic changes associated with different esophageal diseases, including high grade dysplasia, Barrett's disease, and esophageal adenocarcinoma.
AB - Rationale: Mass spectrometry based comparative glycomics is essential for disease biomarker discovery. However, developing a reliable quantification method is still a challenging task. Methods: We here report an isotopic labeling strategy employing stable isotopic iodomethane for comparative glycomic profiling by liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS). N-Glycans released from model glycoproteins and blood serum samples were permethylated with iodomethane ('light') and iodomethane-d1 or -d3 ('heavy') reagents. Permethylated samples were then mixed at equal volumes prior to LC/ESI-MS analysis. RESULTS Peak intensity ratios of N-glycans isotopically permethylated (Heavy/Light, H/L) were almost equal to the theoretical values. Observed differences were mainly related to the purity of 'heavy' iodomethane reagents (iodomethane-d1 or -d3). The data suggested the efficacy of this strategy to simultaneously quantify N-glycans derived from biological samples representing different cohorts. Accordingly, this strategy is effective in comparing multiple samples in a single LC/ESI-MS analysis. The potential of this strategy for defining glycomic differences in blood serum samples representing different esophageal diseases was explored. Conclusions: LC/ESI-MS comparative glycomic profiling of isotopically permethylated N-glycans derived from biological samples and glycoproteins reliably defined glycan changes associated with biological conditions or glycoproteins expression. As a biological application, this strategy permitted the reliable quantification of glycomic changes associated with different esophageal diseases, including high grade dysplasia, Barrett's disease, and esophageal adenocarcinoma.
UR - http://www.scopus.com/inward/record.url?scp=84875204783&partnerID=8YFLogxK
U2 - 10.1002/rcm.6512
DO - 10.1002/rcm.6512
M3 - Article
C2 - 23495056
AN - SCOPUS:84875204783
VL - 27
SP - 865
EP - 877
JO - Rapid Communications in Mass Spectrometry
JF - Rapid Communications in Mass Spectrometry
SN - 0951-4198
IS - 8
ER -