The debate surrounding the use of stem cells in medicine has been a controversial one to say the least. For years, it was believed that the only viable stem cells capable of regeneration came from human embryos. While many were enthusiastic about the prospects of stem cell therapies for the treatment of terminal diseases, others were abhorred at their nature of isolation, and felt it was unethical to obtain them from embryonic sources. Many media personalities, such as the late Christopher Reeves, were major contributors to stem cell research. Individuals like Christopher Reeves have sought to use their influence to show the world the capabilities of stem cell interventions, but proponents of both sides have remained steadfast throughout the years.
Previous research has shown that perhaps the isolation of stem cells may not solely have to come from human embryos. An article posted by Seymour et al. in 2015 in the International Journal of Molecular Sciences highlighted exactly this. During most of the history of stem cell research, it was thought that pluripotent stem cells (PSCs) were exclusively embryonic stem cells (ESCs), until the discovery of adult PSCs in the tissues of adult brains and breasts that displayed characteristics like ESCs indicated otherwise. It’s important to note just what a PSC is. A PSC has been determined to be a master cell of sorts, capable of dividing indefinitely, but perhaps more importantly, is also able to differentiate into cells within the three germ layers (ectoderm, mesoderm, and endoderm). These germ layers lay the foundation of embryonic development, and the entirety of an adult human being is derived from the division and expansion of cells of these three layers in utero (Seymour et al., 2015)
Research of these adult PSCs and the genes regulating their creation and function has shown how crucial their role is in the pubescent development of breast tissue, and the continued functionality of the brain. Without them, breast development is often incomplete or dysfunctional, and the plasticity of the brain is often diminished. However, overexpression of the transcription factors for the proliferation of these cells has also been linked to many cancers, which are resistant to contemporary forms of treatment like chemotherapy (Seymour et al., 2015). Therefore, the continued identification of properties and functionalities of adult PSCs and their transcription factors should remain a focus of stem cell research. If a way can be found to effectively manipulate them to maximize their regenerative properties while minimizing their carcinogenic tendencies, it could redefine regenerative medicine, and subsequently, establish a new direction for the future of medicine.
Seymour, T., Twigger, A. J., & Kakulas, F. (2015). Pluripotency Genes and Their Functions in the Normal and Aberrant Breast and Brain. International journal of molecular sciences, 16(11), 27288–27301. https://doi.org/10.3390/ijms161126024
This is a really cool article, and I wonder what kind of advancements have been made in the research for using adult PSCs since this article has been published. I have actually found an article that has used adult stem cells to create an intestinal organoid (Pleguezuelos‐Manzano, 2020). I also wonder if the ethical stigma that follows stem cells, will decrease once adult PSCs are established as the main source for stem cell research. It will be really interesting to see if there will be a shift in research topics, depending on the type of stem cell used. Other than the ethical implications that come with harvesting embryonic stem cells, do they not also have the potential to have carcinogenic tendencies as adults PSCs that may prevent their public acceptance as a treatment option? I definitely agree that stem cell research should shift from using embryonic stem cells to adult stem cells, especially if it will help decrease the negative view of the public.
ReplyDeletePleguezuelos‐Manzano, C., Puschhof, J., den Brink, S., Geurts, V., Beumer, J., & Clevers, H. (2020). Establishment and culture of human intestinal organoids derived from adult stem cells. Current Protocols in Immunology, 130(1). https://doi.org/10.1002/cpim.106
I found this article very interesting; I had only thought previously that ESCs were a conspiracy theory. I find it interesting the use of PSCs is being seen as a new way of treating various other diseases, whereas ESCs are only allowed to be used to help treat a few diseases. (Tomizawa, 2016) I hope that this technological advancement in stem cells helps clear some of the stigma and allows further funding to continue improving the treatment! Although, do you think there will be a continued need for ESCs if PSCs are able to treat even more diseases?
ReplyDeleteTomizawa, M. (2016). Introductory chapter: Pluripotent stem cells. Pluripotent Stem Cells - From the Bench to the Clinic. https://doi.org/10.5772/64462
This is an interesting article, Mitchell. I think we can all agree that one of the biggest ethical dilemmas in scientific research is how to utilize stem cells in an ethical manner, but to also help people with debilitating conditions. I’m a firm believer that science will solve the problems of tomorrow and recent advancements in stem cell research have shown that we can move away from embryonic stem cells, potentially ending the ethical debate. This was evident in 2006 when Shinya Yamanaka showed that adult cells can be reprogrammed to become pluripotent and differentiate into all three germ lines, winning the Nobel Prize in Physiology. In addition, Delo et al., showed that we don’t have to harvest embryonic stem cells from the embryo, that certain embryonic stem cells are actually present in the amniotic fluid, and harvesting them could pose no risk to the developing embryo.
ReplyDeleteDelo, D. M., De Coppi, P., Bartsch, G., Jr, & Atala, A. (2006). Amniotic fluid and placental stem cells. Methods in enzymology, 419, 426–438. https://doi.org/10.1016/S0076-6879(06)19017-5.
Takahashi, K., & Yamanaka, S. (2006). Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell, 126(4), 663–676. https://doi.org/10.1016/j.cell.2006.07.024.