Dear Editor,
Stem cell surface proteins have been used as markers for isolating and purifying undifferentiated pluripotent stem cells (PSCs),and play important roles in regulating their pluripotency and differentiation.To date,very few specific,highly sensitive markers in PSCs have been identified [1-3].This severely limits their utility in the analysis and recovery of functionally important PSCs.Therefore,it is necessary to expand the repertoire of stem cell markers and to dissect out the molecular mechanisms that regulate pluripotency and differentiation.