Maintenance of human pluripotent stem cells using 4SP-hFGF2-secreting STO cells

► FGF signaling appears to be important in hESC self-renewal. ► FGF2 lacks a signal sequence as it's released from damaged or dead cells. ► We made FGF2 secreted cells, using a lentiviral system tagged FGF4 signal peptide. ► Two types of hESC lines proliferated without differentiation on 4SP-hFGF2 STO cells. ► 4SP-hFGF2 cells may be a simple and economic feeder system for hESCs.