Supplementary Figure 6: MALDI-TOF mass spectrometry of permethylated N-glycans from healthy human neutrophil samples.
From: JAGN1 deficiency causes aberrant myeloid cell homeostasis and congenital neutropenia
N-glycomic profiles of permethylated N-glycans from human neutrophil samples from the healthy mother (a) and father (b) of pedigree C. Profiles of permethylated N-glycans are from the 50% MeCN fraction (Online Methods). Putative structures are based on composition, tandem mass spectrometry and biosynthetic knowledge. Healthy human neutrophil N-glycans included high mannose and complex bi-, tri- and tetra-antennary structures, of which the latter were core fucosylated and non-bisected and mainly terminated with sialylated or fucosylated epitopes. Immature truncated N-glycan structures were found to be relatively minor and were restricted to two core-fucosylated bi- and triantennary structures (m/z = 1,835.9 and 2,040.0; top). Most of the N-glycans are multibranched and are rich in the LeX epitope (Galβ1-4(Fucα1-3)GlcNAc). Of note is the presence of up to three LeX moieties on tri- and tetra-antennary N-glycans (for the mother sample, m/z = 3,402.6, 3,851.7, 4,025.7, 4,212.8, 4,300.8, 4,474.9, 4,749.9 and 4,924.0; bottom). These structures were found to be higher in relative abundance than corresponding glycans with absent or single fucose residues attached on their antennae (for the mother sample; m/z = 3,415.6, 3,864.7, 4,038.8, 4,313.8, 4,487.9, 4,762.9 and 4,937.8).
