Glycomics is the study of comprehensive structural elucidation and characterization of all glycoforms found in nature and further their dynamic spatiotemporal changes are associated with biological processes [1]. Relative to genomics and proteomics, glycomics is just growing out of infancy with great potential in biomedicine for biomarker discovery, diagnosis, and treatment. Lectin microarrays are increasingly used as versatile platform with a high potential for rapid and high throughput glycosylation profiling of biology sample, without the need for the release of glycan. However, weak interaction between lectin and glycan causes low sensitivity of the approach. Here we firstly conjugated lectin on the surface of microspheres assisted by poly-L-lysine (PL) and PEG-diglycolic acid (PEG). The introduction of PL and PEG chain could form a hydrophilic shell to enhance the dispersibility of suspension microarray in aqueous solution and reduce the steric hindrance among the bound lectin for high conjugated amount of lectins. In this report, we present the performance of novel high density lectin suspension microarray in the analysis of standards glycoproteins such as asialofetuin (ASF), fetuin (FET), HRP, ribonuclease B (RNB). Compared with the direct conjugation of lectin suspension microarray, the novel platform shows better dispersibility with 10% (CV) and three to five more sensitivity than first generation suspension microarray [2]. With the high sensitivity and good dispersibility, the novel suspension microarray was applied for serum glycopeptidome analysis from intrahepatic cholangiocarcinoma (ICC) patients. Serum from normal (n=20) and ICC partients (n=20) was analyzed and found that the signature glycan expression in ICC, including α-Fuc, α-Glc, etc. The signature can be explored further as potential biomarker for discovery, diagnosis, and prognostic evaluation of ICC.
[1] Nat. Rev. Cancer 2015, 15(9), 540-555.
[2] Proteomics 2014, 14, 78–86.