Glycomics of human embryonic stem cells and human induced pluripotent stem cells

Most cells are coated by a dense glycocalyx composed of glycoconjugates such as glycosphingolipids, glycoproteins, and proteoglycans. The overall glycomic profile is believed to be crucial for the diverse roles of glycans, which are mediated by specific interactions that regulate cell-cell adhesion, the immune response, microbial pathogenesis, and other cellular events. Many cell surface markers were discovered and identified as glycoconjugates such as stage-specific embryonic antigen, Tra-1-60/81 and various other cell surface molecules (e.g., cluster of differentiation). Recent progress in the development of analytical methodologies and strategies has begun to clarify the cellular glycomics of various cells including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). The glycomic profiles of these cells are highly cell type-specific and reflect cellular alterations, such as development, differentiation and cancerous change. In this mini review, we briefly summarize the glycosylation spectra specific to hESCs and hiPSCs, which cover glycans of all major glycoconjugates (i.e., glycosphingolipids, N- and O-glycans of glycoproteins, and glycosaminoglycans) and free oligosaccharides.