Open AccessThe Cell Surface Glycosphingolipids SSEA‐3 and SSEA‐4 Are Not Essential for Human ESC Pluripotency
Author(s) -
Brimble Sandii N.,
Sherrer Eric S.,
Uhl Elizabeth W.,
Wang Elaine,
Kelly Samuel,
Merrill Alfred H.,
Robins Allan J.,
Schulz Thomas C.
Publication year - 2007
Publication title -
stem cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.159
H-Index - 229
eISSN - 1549-4918
pISSN - 1066-5099
DOI - 10.1634/stemcells.2006-0232
Subject(s) - biology , embryonic stem cell , microbiology and biotechnology , cellular differentiation , flow cytometry , immunostaining , blastocyst , induced pluripotent stem cell , epitope , embryoid body , antigen , embryogenesis , immunology , embryo , biochemistry , immunohistochemistry , gene
Pluripotent cells can be isolated from the human blastocyst and maintained in culture as self‐renewing, undifferentiated, human ESCs (hESCs). These cells are a valuable model of human development in vitro and are the focus of substantial research aimed at generating differentiated populations for cellular therapies. The extracellular markers that have been used to characterize hESCs are primarily carbohydrate epitopes on proteoglycans or sphingolipids, such as stage‐specific embryonic antigen (SSEA)‐3 and ‐4. The expression of SSEA‐3 and ‐4 is tightly regulated during preimplantation development and on hESCs. Although this might imply a molecular function in undifferentiated cells, it has not yet been tested experimentally. We used inhibitors of sphingolipid and glycosphingolipid (GSL) biosynthesis to block the generation of SSEA‐3 and ‐4 in hESCs. Depletion of these antigens and their precursors was confirmed using immunostaining, flow cytometry, and tandem mass spectroscopy. Transcriptional analysis, immunostaining, and differentiation in vitro and in teratomas indicated that other properties of pluripotency were not noticeably affected by GSL depletion. These experiments demonstrated that the GSLs recognized as SSEA‐3 and ‐4 do not play critical functional roles in maintaining the pluripotency of hESCs, but instead suggested roles for this class of molecules during cellular differentiation.