Fig. 4. MALDI-TOF/TOF-MS spectra of the sialic acid-derivatized O-linked glycan from the LEL affinity glycoproteins of the saliva from HVs and T2DM patients. (A) Glycan spectra of HVs and (B) glycan spectra of T2DM patients; the LacNAc-containing O-glycan peaks that increased or decreased in patients with T2DM are marked with red or yellow dotted lines, respectively. (C) Number of O-glycan peaks (LacNAc-containing O-glycan peaks labeled in red) released from LEL-isolated glycoproteins from HV and T2DM samples. (D) Cross-correlation of the LacNAc-containing O-glycan peaks from HVs and T2DM patients are presented in the Venn diagram.