Most cells serve a specific purpose; for instance, white blood cells are specialised to kill microbes in the body and nerve cells can connect to other body parts, interpreting our nerve impulses. However, a stem cell is a non-specific type of cell which can transform into any other cell it wants in the adult body – this skill is called pluripotency. When the stem cell is embryonic, the cell can also become differentiated into placental cells or fertilised egg tissues, called extraembryonic, in which case it becomes totipotent. But, this skill can only become acquired in stem cells early in the embryonic cycle (during its initial few cell divisions (i.e. around the blastocyst stage)). Stem cells main call to fame is that it can replace specialised cells that have been damaged which could potentially prevent diseases like Alzheimer’s or type 1 diabetes by inducing the cells, which are scientifically called iPSCs, induced pluripotent stem cells, to transform into specific cells However, it also brings with it controversy, as well as major effects and possible advantages.
There are various ways to obtain stem cells and many types. There are numerous stem cell types, but the most common/significant stem cells are the embryonic, adult, animal and plant cells. Embryonic cells come from human embryos, hence its namesake, and is the most popular stem cell because it is easy to collect, with the most common method involving using leftover embryos from IVF treatment (where an egg is fertilised by external sperm). Another reason for its popularity is that it has more capabilities – being able to become pluripotent or totipotent. However, adult stem cells, the other main bracket of human stem cells can be pluripotent or multipotent (only able to become specific types of cell) which deems them generally more restrictive in terms of the cells it can specialise into. Consequently, embryonic stem cells are the better choice, but its ethics claim otherwise. This is because many see the utilisation of embryos as callously harvesting fellow humans & believe that the embryos are human too (or with the possibility of becoming one) which raises the question of when human life actually begins. Also, some believe that it trivialises human life which could ultimately lead to more de-humanising actions in the name of science in the future. Geographically, the world’s view also seems to be somewhat split; countries like Sweden, Spain & the UK prohibit stem cell research on human embryos while countries like Germany, Italy along with some American states strictly ban such practices. However, Stem cell researchers are also looking into SCNT (Somatic Cell Nuclear Transplantation) in an attempt to gain pluripotent stem cells from a cloned embryo. SCNT is also the method used to clone ‘Dolly’ the sheep (a clone), which was the first of its kind, so the method has started to gain popularity due to its recent successes like the one just mentioned. This would seem slightly more ethical and, as a result, it would be a more popular way of obtaining those sought-after totipotent stem cells without having to resort to IVF treatments. Moreover, another method along similar lines of reducing unethical rebuke for embryonic stem cell is parthenogenesis in which it is possible to create embryos with donated eggs (specifically for such purpose) without fertilisation. This relates back to the theme of consent which deems it consequently less unethical.
On the other hand, an advantage of adult stem cells is that it lacks such ethical controversy as there is consent involved. These stem cells can also prevent rejection from the ‘security guards’ of the cell although they are harder to attain (than embryonic stem cells). Next, it’s time to distinguish between animal and plant stem cells. However, rather than explaining what both cell types are because that is obvious from the name, it would be more practical to compare how they operate and their characteristics. Animal stem cells are like that of humans with adult stem cells also serving the purpose of replacing damaged cells in animals. However, plant cells have a different method of producing such cells as rather than adult or embryonic cells, they have meristems, a plant tissue which produces totipotent stem cells in the plant. But, they have an advantage over animal cells in that they can divide indefinitely as long as the plant is alive. These meristems can also improve the plant, making it taller or with longer roots and makes a key contribution to the growth of a plant.
The possibilities that stem cells open are potentially endless because by replacing damaged cells, everything from diabetes to cancer could theoretically be stopped due to stem cells. For instance, diabetes involves the lack of pancreatic, insulin-producing cells due to the body’s autoimmune reaction to them. If these were simply replaced with iPSCs which were differentiated into healthy versions of those cells, one would think that diabetes would be prevented. However, scientists still need to consider the autoimmune (body attacking itself) reaction to make sure the same won’t happen with the new cells), so stem cells can be very useful but there are almost always other factors involved with such common diseases. However, there are a few diseases which currently can be prevented solely by stem cells. For example, using bone marrow (a much more universally accepted method of stem cell attainment) is the oldest technique (first to be recognised and used clinically) to finding stem cells and has saved thousands of lives from blood-related cancers like leukaemia. A phenomenon deemed ‘stem cell tourism’ has, however, began to preponderate as people travel overseas in desperation for stem cell treatment that may not be available where they are. This can be successful but often carries danger as such practices may not be thoroughly tested. In addition, stem cells’ possible regenerative ramifications could not just be advantageous in healing diseases or repairing bodily systems but could also involve painlessly using animals to duplicate their body parts which could be an unproblematic way to obtain meat. It may seem far-fetched, but it is just one of the possible stem cell uses that scientists are beginning to pump money into for the future.
In conclusion, stem cell research has unlimited potential (in theory), but it could be argued that scientists can only begin to unlock (or discover) its true potential once the ethical debate is removed from the equation (they need to find more ethical methods of acquiring stem cells).