Induced-Pluripotent Stem Cells

The embryonic stem cells, which are pluripotent cells that are derived from the inner cell mass of the pre-implantation embryo at the blastocyst stage. They are considered as an important finding as they have the potential of self-renewal and differentiate indefinitely into the three germ layers, the endoderm, mesoderm and the ectoderm. The human embryonic stem cells were considered to be useful in clinical applications, as they have the potential to be used in cell therapies on diseases like Parkinson’s disease, diabetes and spinal cord injury. However, this research faced a huge ethical difficulty in the use of human embryos, especially in some conservative countries and the religious issue. Also there was the problem on tissue rejection from the transplantation to the patients. In 2006, Yamanaka and his colleagues had discovered that differentiated cells could be reprogrammed back to an embryonic-state like by combining several transcriptional factors. They were able to generate what is now called the induced pluripotent stem cells from either mouse embryonic or the adult fibroblast cultures, which demonstrated huge similarities to embryonic stem cells, such as the morphology and growth properties. The induced-pluripotent stem cells could have do the same job as embryonic stem cells, while avoiding the ethical issues and tissue rejection as they were made from the patient’s own cell. In this essay, we will discuss the production and the concept of induced-pluripotent stem cells, the difference and similarities between the induced-pluripotent stem cells, the possible usage of induced-pluripotent stem cells and the barrier they are facing.
Yamanaka and his colleagues in 2006 found that 4 transcriptional factors, Oct3/4, Sox2, c-Myc and Klf4 plays an important role in making the induced-pluripotent stem cells. They made this observation by introducing 24 candidate genes into mouse embryonic fibroblasts from Fbx15ßgeo/ßgeo embryos by retroviral transduction