A New Way to Induce Stem Cells

Harvard's Derrick Rossi and his colleagues report in Cell Stem Cell on a way to use synthetic messenger RNAs to have differentiated human cells to regain their pluripotency. Rather than relying on viruses, messenger RNA delivers the four proteins needed to induce pluripotency. The authors write that "because our technology is RNA based, it completely eliminates the risk of genomic integration and insertional mutagenesis inherent to all DNA-based methodologies." In addition, Technology Review notes that using RNA looks to be "as much as 100-fold more efficient" than DNA. "We now have an experimental paradigm for generating patient-specific cells highly efficiently and safely and also taking those cells to clinically useful cell types," Rossi tells the Washington Post. Francis Collins adds that this is a "substantial advance" but that it "in no way reduces the importance of comparing the resulting iPS cells to human embryonic stem cells. Previous research has shown that iPS cells retain some memory of their tissue of origin."