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Updated: Apr 28, 2026
Biobanking of Human Aqueous and Vitreous Liquid Biopsies for Molecular Analyses
Published on: September 11, 2023
A comparison of N-glycan profiles in human plasma and vitreous fluid
Saori Inafuku1, Kousuke Noda, Maho Amano
1Laboratory of Ocular Cell Biology and Visual Science, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Purpose:
To investigate the concentration and composition of N-glycans in plasma and vitreous samples obtained from patients with non-proliferative vitreoretinal diseases.
Methods:
Plasma and vitreous samples were collected from 11 patients with idiopathic macular hole (MH) and 9 patients with epiretinal membrane (ERM). The samples were pretreated for enzymatic cleaving, and subsequently glycans released from proteins were captured on BlotGlyco H beads. Sialic acids were methyl-esterified. Processed glycans were tagged with aminooxy-functionalized peptide reagent (aoWR) and released from the beads, followed by detection by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The concentration and composition of N-glycans in the samples were assessed.
Results:
Concentration of N-glycans in vitreous samples (132 ± 29 pmol/100 μg protein) was significantly lower compared with those in plasma samples (714 ± 29 pmol/100 μg protein, p < 0.001). Predominant N-glycan in both plasma (39.7 ± 1.1 %) and vitreous fluid (37.2 ± 3.1 %) was identical, and the composition was presumed as [(Hex)2(HexNAc)2(NeuAc)2+ (Man)3(GlcNAc)2]. By contrast, the second-ranked N-glycan in vitreous samples (15.6 ± 1.5 %) was the seventh in plasma (2.3 ± 0.2 %).
Conclusions:
The current data provide useful information on N-glycan profile in the vitreous fluid, which is distinct from that in the plasma.
