High-throughput IgG Fc N-glycosylation profiling by mass spectrometry of glycopeptides

MP Baković, MHJ Selman, M Hoffmann… - Journal of proteome …, 2013 - ACS Publications
MP Baković, MHJ Selman, M Hoffmann, I Rudan, H Campbell, AM Deelder, G Lauc
Journal of proteome research, 2013ACS Publications
Age and sex dependence of subclass specific immunoglobulin G (IgG) Fc N-glycosylation
was evaluated for 1709 individuals from two isolated human populations. IgGs were
obtained from plasma by affinity purification using 96-well protein G monolithic plates and
digested with trypsin. Fc N-glycopeptides were purified and analyzed by negative-mode
MALDI-TOF-MS with 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrix. Age-associated
glycosylation changes were more pronounced in younger individuals (< 57 years) than in …
Age and sex dependence of subclass specific immunoglobulin G (IgG) Fc N-glycosylation was evaluated for 1709 individuals from two isolated human populations. IgGs were obtained from plasma by affinity purification using 96-well protein G monolithic plates and digested with trypsin. Fc N-glycopeptides were purified and analyzed by negative-mode MALDI-TOF-MS with 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrix. Age-associated glycosylation changes were more pronounced in younger individuals (<57 years) than in older individuals (>57 years) and in females than in males. Galactosylation and sialylation decreased with increasing age and showed significant sex dependence. Interestingly, the most prominent drop in the levels of galactosylated and sialylated glycoforms in females was observed around the age of 45 to 60 years when females usually enter menopause. The incidence of bisecting N-acetylglucosamine increased in younger individuals and reached a plateau at older age. Furthermore, we compared the results to the total IgG N-glycosylation of the same populations recently analyzed by hydrophilic interaction liquid chromatography (HILIC). Significant differences were observed in the levels of galactosylation, bisecting N-acetylglucosamine and particularly sialylation, which were shown to be higher in HILIC analysis. Age and sex association of glycosylation features was, to a large extent, comparable between MALDI-TOF-MS and HILIC IgG glycosylation profiling.
ACS Publications