A new literature analysis confirms what stem cell scientists have been saying for some time: Studies of induced pluripotent stem cells (iPSCs), which are touted as an ethical alternative to human embryonic stem cells (hESCs), often involve hESCs as well. As a result, research that restricts funding for hESCs would also harm iPSC research.
HESCs are derived from human embryos, while iPSCs are made by reprogramming adult cells. In a study in the 10 June issue of Cell, Stanford University bioethicist Christopher Thomas Scott and colleagues analyze 2086 publications on hESCs and iPSCs from 1998 through 2010. While the number of publications using iPSCs has shot up since the first report on these cells in 2007, 100 of 161 iPSC papers (62%) published last year used both types of cells. Established investigators in particular tended to include hESCs, which are often used as controls.
Many researchers are worried that a lawsuit claiming federally funded hESC research violates a ban on research that destroys human embryos could stymie their work. The authors say that any decision by the courts or by legislators to limit funding for hESCs "will also have disastrous consequences for [iPSC funding] because research using the two different types of cell lines is deeply, perhaps inextricably, intertwined."