By Mubashra Inam
When the cells are grown in culture, they multiple into the cells of the same type being cultured. For instance, melanocytes produce melanocytes, osteocytes multiply into osteocytes and so on. However, there are specialized cells in human body that can be differentiated into different, if not all, types of cells upon development. These cells are named as stem cells(1). Biotechnologists and bioengineers have exploited this ability of stem cells for the welfare of human beings, primarily, the treatment of genetic disorders or other medical conditions. Hence, the study of stem cells and its modifications to use them as a treatment has led to the new field of scientific research known as stem cell therapy. Stem cells studies have opened a window to the cure of medical conditions which was not available before. However, expanding research in this field has also raised financial and ethical concerns related to its continuity. This piece of writing will shed light upon the types of stem cells used for stem cell therapy, brief methodology and dilemmas, primarily ethical, surrounding it. The waythese dilemmas can be dealt with also be discussed.
There are two main types of stem cells used for stem cell therapy. First type is adult stem cells (ASCs) that are pluripotent (restricted to differentiation into a few types) such as mesenchymal stem cells and hematopoietic stem cells. The second is embryonic stem cells (ESCs) that are totipotent (can differentiate into almost all types of stem cells). There are induced pluripotent stem cells (iPSCs) which are actually pluripotent cells derived from ASCs and are genetically reprogrammed to ESC-like state to force the expression of genetic conditions significant for defining characteristics of ESCs(2).
As to how these cells are used for therapy, it is fairly simple in words but difficult to perform. Researchers grow stem cells in labs and these cells are manipulated to produce the specific cell type required for therapy. These manipulations change the genetic expression of the cells. The modified cells are then implanted to the specific region into the patient body(3). For instance, if this therapy is used for patient suffering from spinal cord injury, the stem cells are injected into the affected vertebra. The most widely known stem cell therapy is bone marrow transplant, as bone marrow contains adult stem cells, Although, it has been effective in treating cancers, it has various limitations, most significant of which is bone marrow tissue matching. However, recent researches are based on the use of embryonic stem cells and iPSCs for treating different medical conditions.
Embryonic stem cells, as mentioned above, have the ability to differentiate into many types of cells. For ESC therapy, human embryos are used to obtain ESCs. After In-vitro fertilization (IVF), the embryos which are no not implanted in the woman’s uterus and are no longer required are grown for and subjected to stem cell therapy, with the consent of donor. Here lies the basic ethical concern surrounding ESC therapy i.e., the destruction of human embryos. Because of that, it is necessary to consider the moral status of human embryo i.e., if it is recognized as a being endowed with human dignity and if it has a right to life as compared to that of born human beings. Destruction of embryos for research purposes raises the serious ethical concerns of exploitation, manipulation and killing of human beings(4).Another ethical consideration is research cloning i.e., the obtaining of embryos for research purposes by nuclear transfer in enucleated egg cells.Research cloning of humans would represent a clear occurrence of exploiting humans solely for the benefit and interests of others. Establishing this technique in humans requires further destructive embryo research and is apprehended to prepare a slippery slope for reproductive cloning of humans, which is generally considered as ethically unacceptable.
A major hindrance that we do not consider is the reluctance on the part of many scientists to take time to understand the nature of the ethical concerns and begin developing reasoned ethical responses to these concerns if the stem cell therapy is to be continued. Those involved in the ethical and political debate about the generation and use of ESCs must understand the complexity and dilemmas of the research. Researchers who use “ethically sensitive material” play a significant role in informing these debates and will be in the best position to do so when they develop their ethical reasoning skills and their abilities to discuss and defend their work on ethical grounds(5). Therefore, it is advised to perform the research on stem cell therapy under the thorough oversight of the ethic committees and justifying the research to circumvent the scientific and ethical roadblocks.
REFERENCES
1. Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular biology of the cell: WW Norton & Company; 2017.
2. Ye L, Swingen C, Zhang J. Induced pluripotent stem cells and their potential for basic and clinical sciences. Curr Cardiol Rev. 2013;9(1):63-72.
3. Ethik NIoHJJfWu. National Institutes of Health guidelines on human stem cell research. 2010;15(1):475-84.
4. Weiss AM, Breitenbach M, Rinnerthaler M, Virt Gn. Ethical Considerations on Stem Cell Research. Pluripotent Stem Cells: IntechOpen; 2013.
5. Gruen L, Grabel L. Concise Review: Scientific and Ethical Roadblocks to Human Embryonic Stem Cell Therapy. 2006;24(10):2162-9.
