Regenerative Medicine and Stem Cells Technologies

 A recent study published in Nature Chemical Biology has found a method its authors say improves on the Nobel prize-winning cellular reprogramming method developed by Shinya Yamanaka, M.D., Ph.D. — making it possible to produce cells in a considerably shorter time and with greater success.

Dr. Yamanaka"s method obtains pluripotent cells, similar to the ones we know exist in the very early stages of the embryo. Since such cells are obtained by transforming existing cells of the body such as skin cells, they are referred to as induced pluripotent stem cells (iPSCs).

While transformative and hugely important, Dr. Yamanaka"s reprogramming method needed improvement in two regards: 1) the transformation of cells takes a long time — around three to four weeks; and 2) the rate of successful reprogramming was rather low at around one in 100,000.

Now, Tamer Önder, Ph.D., of Koç University School of Medicine and doctoral students Ayyub Ebrahimi and Kenan Sevinç, along with Udo Oppermann, Ph.D., of Oxford University and his team, have shortened this waiting period and increased the success rate.

The challenge of the viruses used to transfer the Yamanaka factors to the skin cells sometimes acting rebelliously and inserting themselves to arbitrary parts of the chromosomes led Dr. Önder to investigate the use of certain chemicals instead. After targeted trials, the team observed that two chemicals produced the desired results in turning skin cells to stem cells. This meant that two of the four Yamanaka factors were no longer necessary. And applying the method with two factors instead of four has reduced the waiting period to approximately a week.

Even more importantly, the success rate increased up to as high as 10-fold.

The next phase of the research will involve eliminating the other two Yamanaka factors, too. In this way, it will be much easier to apply the method in clinical settings; as viruses will no longer be needed, there will be no danger of manipulating with the wrong gene or involuntarily suppressing the effects of a particular gene.

Reference:https://www.nature.com/articles/s41589-019-0264-z