|Human embryonic stem cells in cell culture|
It's true, most of the people have a general idea of the controversy arising from the use of stem cells. However, there are many different types stem cells, created or derived using a plethora of different techniques from an equally large plethora of sources. Not all stem cells are created by destroying embryos and not all stem cells have the same differentiation capacity, advantages, disadvantages etc.
Before moving to the actual prons and cons, lets first explain some basic things about stem cells. What is a stem cell? Stem cells are cells with the capacity to transform themselves into other, more specialised cells, like muscle cells, neurons, skin cells and all the other cells our bodies are comprised of.
Today, medical research is focused on three particular types of stem cells: embryonic, adult and induced pluripotent stem cells. The first type is found in embryos. The second type is found in a great number of tissues and organs including bone marrow, blood, adipose tissue and liver. As for induced pluripotent stem cells, they are artificial stem cells created by reverting differentiated cells (e.g. skin cells) back into a stem cell like nature. If you want to learn more about the various types and subtypes, I suggest you to begin with our article on what stem cells are. The article begins with all the basics and gradually digs deeper and deeper into the world of these very promising cells.
A mesenchymal stem cell, a sub-type of adult stem cells
Unlike embryonic, adult stem cells don't require the
destruction of an embryo
Now, let's see the prons & cons of each of these three aforementioned stem cell types.
Stem Cell Advantages
Stem Cell Disadvantages
- Hematopoietic stem cells already save thousands and thousands of patients each and every year. The are patients with cancer and several rare blood diseases. If it wasn't for stem cells, these people would most certainly die.
- Stem cell reseach continuously provide us with new, precious insight on a great variety of currently untreatable diseases like Parkinson's, Alzheimer's, cancer, osteoarthritis just to name a few. For example, studying embryonic stem cells help us learn more about human growth, cell development and what sometimes goes "wrong" during this process and why.This insight will be critical in one day treating these diseases, even if the actual treatment is not stem cell-based.
- Most scientists agree, stem cells are the key to one day grow tissues, organs and perhaps limbs. This is not sci-fi. This happens today! Researchers have already grown and transplanted simple organs, using a combination of stem cells and scaffolds.
- Researchers have already created disease-in-a-dish models for a plethora of different conditions like Alzheimer's. Once this becomes standard practise, it will greatly reduce the need of clinical trials on animals and humans alike. Creating many of these models would be impossible without the help of induced pluripotent stem cells.
- Stem cells have already shown some very promising results in people with spinal cord injuries. Who knows, they may one day allow people with debilitating SCI injuries to walk again.
- Not all stem cells require the destruction (or killing if you prefer) of a human embryo. Adult and induced pluripotent stem cell lines can be developed using a piece skin or a bone marrow sample. Heck, a pinch of blood is enough!
- Unlike embryonic, adult and induced pluripotent stem cells are autologous, meaning that they are developed from the patient himself. Which in turn means little to none risk of rejection for stem cell based treatments. This also means that there will be no need for using immunosuppressive drugs once such treatments are available.
- The knowledge gained by studying stem cells give us a better understanding of ageing. Perhaps the key for delaying, halting or even reversing ageing is just a few decades away!
Stem Cell Disadvantages
- The use of human embryonic stem cells requires the destruction of laboratory-fertilised human eggs. Many view the blastocysts destroyed during the process as just a mass of cells, while believe that life begins at conception and thus consider the whole process to be immoral and unacceptable.
- Both embryonic and induced pluripotent stem cells have a tendency to forming tumours. On the other hand, adult stem cells don't seem to have this problem, due to their limited differentiation nature.
- We will have to wait many years, perhaps decades before seeing widespread clinical application of stem cell therapies, with the exception of course hematopoietic stem cell transplantation.
- Having an an experimental, none FDA approved treatment is dangerous and may prove to be deadly. This of course applies to many of the experimental, not FDA approved stem cell therapies provided all over the world by clinics and individual physicians.