Human Stem Cell Glycome: From Structural Elucidation to Social Implementation

Abstract

We analyzed the glycan structure expressed in human pluripotent stem cells (hPSCs) using high density lectin microarray and mass spectrometry. α2-6Sia, α1-2Fuc, type1 lactosamine structure was found to be increased in hPSCs as compared with the differentiated somatic cells. Dramatic changes were found in sialic acid on N-glycans. While human induced pluripotent stem cells (hiPSCs) were all of α2-6 type, human fibroblasts were all of α2-3 type. Examination of the glycan structure of human mesenchymal stem cells (hMSCs) and cartilage tissue-derived chondrocytes revealed that the proportion of α2-6sialyl N-glycans is high in cells capable of differentiation. Then, H type 3 (Fucα1-2Galβ1-3GaINAc) was found as a new cell surface marker characterizing hPSCs. This carbohydrate epitope was expressed on type1 transmembrane protein, podocalyxin. In addition, we discovered a recombinant lectin named rBC2LCN as a probe specifically recognizing this structure. By utilizing rBC2LCN, we developed three key technologies to overcome the risk of tumorigenicity of hPSCs: live staining method, detection method using cell culture media, and elimination method. In this mini-review, we will overview our research findings from structural elucidation of glycans expressed on hPSCs to social implementation.