Premium
Profiling of Endo H‐released serum N ‐glycans using CE‐LIF and MALDI‐TOF‐MS – Application to rheumatoid arthritis
Author(s) -
Frisch Elena,
Kaup Matthias,
Egerer Karl,
Weimann Andreas,
Tauber Rudolf,
Berger Markus,
Blanchard Véronique
Publication year - 2011
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.201100250
Subject(s) - glycan , glycoprotein , mannose , mannan binding lectin , chemistry , mannosidase , glycome , rheumatoid arthritis , glycosylation , context (archaeology) , lectin , biochemistry , immunology , biology , paleontology
Abstract High‐mannose and hybrid‐type N ‐glycans are present in human serum glycoproteins in low abundance but have recently been described to play an important role in immune responses. It is therefore important to find a strategy to selectively analyze their structures in the context of health and disease in order to understand their impact on disease mechanisms. We report here the characterization of high‐mannose and hybrid‐type N ‐glycans in total human serum. To this end, N ‐glycans were released using Endo‐β‐ N ‐acetylglucosaminidase H (Endo H) and analyzed by CE‐LIF and MALDI‐TOF‐MS. We found that the high‐mannose structures Man 5–9 GlcNAc 1 represented the majority of the pool. The monoglucosylated structure Glc 1 Man 9 GlcNAc 1 as well as four hybrid structures could be identified. Then, we compared the Endo H‐released serum glycome of patients suffering from rheumatoid arthritis with healthy controls as mannose‐binding lectin deficiency (MBL) and modulation of α‐mannosidase activity were previously associated with this disease. Interestingly, we observed that both high‐mannose and hybrid structures were fairly constant, suggesting that circulating MBL and α‐mannosidase may not affect significantly the levels of serum glycoproteins carrying these glycans.