A research team led by Dr. John Yu, Distinguished Research Fellow at the Institute of Cellular and Organismic Biology (ICOB) has discovered that glycosphingolipids on the surface of cells change composition when human embryonic stem cells differentiate into precursors of specialized cells such as neurons, or liver and pancreas cells. These findings, which contribute to the search for safe ways of using stem cells for regenerative medicine, were published in the online edition of the journal Stem Cells on November 16.

        Regeneration of damaged tissues is one of the holy grails in medical research, and embryonic stem cells, with their ability to renew themselves and differentiate into a diverse range of specialized cell-types, are considered a promising source for cell replacement therapies. Unfortunately, alongside their differentiation ability, embryonic stem cells also have a propensity to develop into tumors, a characteristic that currently presents a large obstacle to their clinical use.

The team of researchers from the ICOB, Genomics Research Center (GRC) and Institute of Biological Chemistry recently discovered that a type of compounds found on the surface of human embryonic stem cells, called glycosphingolipids, change composition as the cells differentiate into precursors of specialized cells such as neurons and liver cells. These findings suggest that glycosphingolipids might be suitable for use as markers of the state of differentiation of stem cells. A knowledge of the state of differentiation of these cells may allow researchers to develop a method by which to sort undifferentiated cells from those that are differentiated, and thus, perhaps allow removal of the undifferentiated cells most likely to form tumors bringing the safe regeneration of human cells or organs one step closer.

The team, including Dr. Chia-Ning Shen, Assistant Research Fellow at the GRC, and Dr. Kay-Hooi Khoo, an Adjunct Research Fellow at the GRC studied the compounds using matrix assisted laser desorption ionisation (MALDI) MS mass spectrometry technology. They found that during differentiation into neural progenitor cells, the core structures of glycosphingolipids on human embryonic stem cells switched mostly to the ganglio-series type. On the other hand, when human embryonic stem cells differentiated into endodermal cells (precursors of liver and pancreas cells), the prominent glycosphingolipid identified was Gb4Cer.
        Dr. Yu, who is also an Adjunct Distinguished Research Fellow at the GRC said that he hopes the advance will pave the way for developing new strategies for safer stem cell-based therapies in regenerative medicine.

The research entitled "Changes in Glycosphingolipid Composition During Differentiation of Human Embryonic Stem Cells to Ectodermal or Endodermal Lineages" can be found online on the Stem Cells website at: http://onlinelibrary.wiley.com/doi/10.1002/stem.750/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+5+Nov+from+10-12+GMT+for+monthly+maintenance

The complete list of authors is: Yuh-Jin Liang, Bei-Chia Yang, Jin-Mei Chen, Yu-Hsing Lin, Chia-Lin Huang, Yuan-Yuan Cheng, Chi-Yen Hsu, Kay-Hooi Khoo, Chia-Ning Shen, and John Yu.