The ability to easily generate adult iPSCs enables many intriguing therapeutic and drug development approaches. For example, patients with numerous intractable diseases could be treated with autologous stem cells that are derived from their own cells, and thus do not risk rejection by the immune system. It may also be possible to use iPSCs to develop new disease models for complex multigenic diseases.  Lastly, iPSCs may be good models for drug efficacy and toxicity screens.

A variety of approaches have been used to create iPSCs. Most of these approaches involve the expression of several “reprogramming factors” in cells, which direct them to become stem cells. Early approaches used expression plasmids or lentiviral vectors to express these reprogramming factors. While effective at generating iPSCs, these approaches suffer from the danger of insertional mutagenesis by the expression vector, leading to cancer. The vast potential for stem cells to divide repeatedly makes insertional mutagenesis a special concern since stem cells already have many characteristics of cancer cells.

Recently, Derrick Rossi’s laboratory at Harvard described a new strategy for iPSC formation that had no risk of insertional mutagenesis. They used a cocktail of capped and poly adenylated messenger RNAs (mRNAs) expressing five reprogramming factors (Cell Stem Cell. 7:618-30). They built upon results from the Kariko laboratory at the University of Pennsylvania that showed that transfected mRNA induces innate immune responses and toxicity. This toxicity could be ameliorated by substitution of cytidine and uridine with 5-methylcytidine and pseudouridine. The Rossi laboratory showed that daily transfection with 5-methylcytidine and pseudouridine substituted mRNAs resulted in highly efficient reprogramming to pluripotency. They observed reprogramming efficiencies that were ~30 fold higher than those achieved using lentiviral vectors.

TriLink offers custom mRNA synthesis including mRNAs substituted with 5-methylcytidine and pseudouridine. One or more pending or issued patents may govern the commercial use of modified mRNAs for the reduction of innate immune responses and the use of reprogramming factors for the production of iPSCs.

Contact us today to discuss your project.