Figure 4.

Overview on the N-glycome of CEA immunoprecipitated from Mock and MST3Gal IV cells. N-glycans were released from immunoprecipitated CEA, analyzed by porous graphitized carbon nanoLC-ESI-MS/MS and qualitatively and quantitatively assessed. The N‑glycans were classified into 3 classes: oligomannose (green), mono sialylated (blue) and di sialylated (purple). A - CEA immunoprecipitated from Mock and MST3Gal IV cells exhibited different complex N-glycan profiles despite similar levels of oligomannose N-glycans. Mock cells expressed CEA was mainly carrying monosialylated N-glycans while disialylated N-glycans were the major complex type N-glycans in MST3Gal IV overexpressing cells. B - Mock cell derived CEA carried type II N-glycans (Galβ1-4GlcNAc) capped with α2-6 linked NeuAc (light blue) while CEA from MST3Gal IV cell lines carried type II N-glycans capped with α2-3 linked NeuAc (purple). The major sialylated N-glycan structures of immunoprecipitated CEA were highlighted on top of each linkage type. The symbol nomenclature for glycans (SNFG) recommendations were followed for glycan structure depiction ²⁷. Detailed information of the identified N-glycans is summarized in Table S2 and Figure S2.