Genetic engineering of human embryonic stem cells with lentiviral vectors

Human embryonic stem ( hES) cells present a valuable source of cells with a vast therapeutic potential. However, the low efficiency of directed differentiation of hES cells remains a major obstacle in their uses for regenerative medicine. While differentiation may be controlled by the genetic manipulation, effective and efficient gene transfer into hES cells has been an elusive goal. Here, we show stable and efficient genetic manipulations of hES cells using lentiviral vectors. This method resulted in the establishment of stable gene expression without loss of pluripotency in hES cells. In addition, lentiviral vectors were effective in conveying the expression of an U6 promoter- driven small interfering RNA ( siRNA), which was effective in silencing its specific target. Taken together, our results suggest lentiviral gene delivery holds great promise for hES cell research and application.