Induced Pluripotent Stem Cells
What Are Induced Pluripotent Stem Cells
Induced pluripotent stem cells (iPS cells) are differentiated cells that are reprogrammed back into an embryonic-like state, they derive from skin or blood cells, iPS cells are not controversial, because they are made from adult cells. As pluripotent stem cells, they can give rise to nearly all of the tissues that form the human body. Induced pluripotent stem cells are a type of pluripotent stem cell that can be generated directly from a somatic cell. The iPSC technology was pioneered by Shinya Yamanaka’s lab in Kyoto, Japan, who showed in 2006 that the introduction of four specific genes, collectively known as Yamanaka factors, encoding transcription factors could convert somatic cells into pluripotent stem cells
Induced pluripotent stem cells (iPS cells or iPSCs) are commonly derived from blood or skin cells that have been reprocessed back to an embryonic-like state. This allows for the development of various human cell types for therapeutic uses. iPS cells can be made in several ways depending on its type. One method is genetic reprogramming. Some labs use a handful of genes to reprogram a normal cell, like a skin cell, into an IPSC. Klf4, Myc, Sox2, and Oct4 are genes commonly introduced into a cell using viruses.
Induced pluripotent stem cells (iPSCs) are generated from adult cells by the overexpression of four transcription factors Oct4/3 (octamer-binding transcription factor 4/3), Sox2 (sex determining region Y), Klf4 (kruppel-like factor 4) and c-Myc (Avian Myelocytomatosis virus oncogene cellular homologue). The iPSCs at cellular level are almost similar to ESCs as they are having the capacity of self-renewal, differentiation potential and the ability to produce germ line competent-chimeras. After these findings, two groups Takahashi et al. and Nakagawa et al. [have generated the iPSCs from adult human fibroblasts. Though iPSCs possess great potential for cell therapy, their genomic stability is still questionable.
One advantage of iPS cells is that they can be created without requiring human embryos, which carry ethical issues and controversy. Another benefit is that iPS stem cells allow the creation of isogenic control cell lines through CRISPR/Cas9 gene editing. This gene editing permits the changing of DNA to treat human diseases using cells.
iPSCs are similar to embryonic stem cells (ES cells) in many ways, such as proliferation, morphology, expression of pluripotency markers, and teratoma formation. PSCs also express genes and stem cell surface markers that distinguish ES cells, like TRA-1-81, TRA-1-60, Sox2, and Oct4.
An illustration showing different types of stem cell in the body.
Image credit: Genome Research Limited
Induced pluripotent stem cells
- Induced pluripotent stem cells, or ‘iPS cells’, are stem cells that scientists produce in the laboratory from Adult stem cells.
- ‘Induced’ means that they are made in the lab by taking normal adult cells, like skin or blood cells, and reprogramming them to become clean, fresh stem cells; with no prior memory of what they were before. Just like embryonic stem cells, they are pluripotent so they can develop into any cell type.
iPSCs definitely have the potential for medical applications. They can be used for regenerative medicine support, screening and developing new drugs, and understanding different types of diseases. For example, in creating new drugs, researchers can use cultured stem cells to test drugs and help them understand its therapeutic possibilities.
Immune rejection is also minimized because the stem cell sample is taken from the patients themselves. This reason alone creates a promising window for iPSC to contribute to advancements in therapeutic medicine.
iPS cells, just like other types of stem cells, promise a brighter future for regenerative medicine. They can be modified into a cell type to match the therapeutic need of the disease being treated. It is still important to consider, however, that continued research is needed to understand the behavior and mechanisms of iPS stem cells.
One challenge in research about iPS cells is that the change in DNA creates a forced expression of the genes. This situation cannot be controlled completely, leading to unpredictable effects. In terms of clinical application, these cells require an efficient and safe generation of stem cells to achieve the full effectiveness of the reprogramming process.
Researchers are still in the phase of understanding these cells’ molecular mechanisms relating to reprogramming.