Essay: Induced pluripotent stem cell treatment (iPS)

Embryonic stem cells have been considered to help treat many diseases including Parkinson’s and cardiac myopathy. ESC therapy involves replacing the damaged cells in a patient with ESCs. Although it sounds promising, this cell therapy has raised many ethical questions regarding the manner in which the cells are obtained. A possible solution to this dilemma is the use of induced pluripotent stem cells. The discovery of these cells was made in the year 2006 by Shinya Yamanaka and his team from Kyoto University in Japan (1).  Yamanaka and his team were able to reprogram adult skin cells obtained from mice into cells that behaved more like embryonic stem cells. They were able to do this by reprogramming 4 specific genes (Oct ¾, Sox2, Klf4, and c-Myc) in the cells. These genes were cloned into viral vectors and added to the culture of skin cells, the results were the iPS cells (2). After this discovery Yamanaka presented his findings to scientists at the 2006 International Society for Stem Cell Research annual meeting. Since this meeting, scientists have been studying iPS cells to reproduce Yamanaka’s results.  Kyoto University’s Center for iPS Cell Research and Application has been developing an iPS cell bank under the leadership of Yamanaka. They have been leading the research in this field as of now and continue to do so, especially with their role in the first ever human trial.
In 2014, a 77- year old woman with age-related macular degeneration underwent the process of having iPS cells used to treat her condition (3). This operation was performed by Masayo Takahashi, an ophthalmologist at the RIKEN Center for Developmental Biology in Kobe, Japan and Yamanaka. This operation proved effective; the patient reported clearer vision with no apparent issues. There was another trial being planned but it was cancelled due to minor genetic mutations in the patient’s iPS cells. This of course raised a concern about uncontrolled growth of these cells which could in turn cause cancer. This is one of the many concerns being brought up by this treatment. Two other major concerns that have been considered are those of donor privacy and the possibilities of cloning. The privacy of cell donors is questioned due to the DNA present in these cells, the DNA contains a multitude of genetic information about the donor and it is not altered in the iPSC making process (4). This information could be misused and result in the violation of that donor’s privacy. A possible solution would be to make donor information anonymous but this presents another issue; the scientists might have to ask follow up questions to ensure the health of the donor so they must have the donor’s information available. Human cloning is another important issue to consider when discussing further uses of iPS cells. There has been one successful trial in which researchers were able to derive gametes from mouse cells using the iPS cell technology (4). These complications have actually created a new horizon for scientists, instead of using it in humans they are focusing on using the iPSCs to help patients in other ways.
iPSCs have been used to study diseases in humans and to find new drug treatments. Scientists have been able to create organoids from iPS cells in order to mimic the effects of diseases such as the Zika virus . In the case of the Zika virus, scientists wanted to understand how the disease could affect a pregnant woman’s fetus developing microcephaly. They created a brain organoid, exposed it to Zika, and found that the disease infects neural stem cells over new neurons leading to the death of those cells and a decrease in the number of layers of neurons in the cortex (2). iPS cells have also been used to discover new drug treatments and the way patients could respond to them. In 2012, scientists used cells from patients with a nerve-cell-developmental disease to screen 7,000 molecules and identify a possible drug for the treatment of the disease (1). This would mean that the possibilities of finding cures for diseases has increased.