The cells that stem and supply our cells
I’m a Psychology and English student, and I love science. Whether it’s physics, chemistry, or biology, I love the methodology, I love the sense of learning, and I love the feeling of discovery. The only problem is that I don’t seem to be very good at science. What I am good at, however, is writing and explaining things that I’ve learned – which is the idea behind
Science Avenue. Every issue, I’ll write about a different scientific or technological concept and attempt to answer four questions: What is X? How does X work? Why is X important? What is the future of X? My goal is to try to spread a basic understanding of how the universe fits together for anyone who’s ever looked to the stars and wondered, “How?”
What are stem cells?
Complex problems are only ever complicated when one observes them from a distance. The most detailed and elaborate puzzles only ever seem confusing when you try to understand what each part does as a whole. So, what are stem cells? They’re undifferentiated biological cells that can become specialized cells, divide to make more specialized cells, and divide to make more stem cells. A stem cell is merely a cell that has no speciality; unlike brain cells in the nervous system, or blood cells in the circulatory system, stem cells have no purpose other than to make specialized cells and more stem cells.
How do stem cells work?
There are two “types” of stem cells, and both can create specialized daughter cells and more stem cells. Adult stem cells are somatic (body) cells that are found throughout the body, and are found in children and adults despite their name. The “adult” in adult stem cells actually refers to the cell’s ability to create specialized cells and stem cells. Typically, when an adult stem cell divides, it makes one “daughter” cell and one more stem cell. The daughter cell is a specialized (differentiated) cell, while the stem cell is an unspecialized (undifferentiated) adult stem cell.
Embryonic stem cells (ESC) are so named because they are gathered from organisms during the embryonic stage of development. Unlike adult stem cells, ESCs are capable of dividing into any of three kinds of somatic cells. This means that ESCs are quite literally capable of becoming any kind of cell in the entire body. An ESC’s ability to divide into any kind of cell is called pluripotency; ESCs are considered pluripotent.
Why are stem cells important?
Stem cells aid in the formation, maintenance, and regeneration of somatic cells, tissues, and organs. The 20 000 or so stem cells that every human is born with are more than capable of dividing themselves to death, despite the fact that every adult stem cell forms another adult stem cell during cell division. Furthermore, ESCs, with their ability to become any kind of somatic cell, could lead to aiding sufferers of diabetes, severe heart conditions, and nervous system deficiencies, and even make it possible to clone organs.
If harnessed and understood, stem cells could make it possible for patients on transplant lists to receive organ donations from themselves. Doctors would simply need to coerce stem cells to become cells that form lungs, livers, or hearts and transplant the organs.
However, controversy surrounds ESCs because they are normally only gathered from undeveloped embryos and umbilical cord blood immediately following birth. Ultimately, the chief controversy with stem cells has nothing to do with biology and everything to do with the conceptual question of “When does life begin?”
What is the future of stem cells?
In 2006, researchers Shinya Yamanaka and John Gurden began work on artificially causing regular somatic cells to differentiate into stem cells. Through a combined manipulation of genes and transcription factors (the passing down of different gene properties), Yamanaka and Gurden were able to create Induced Pluripotent Stem Cells (IPSC).
Yamanaka and Gurden’s research earned them the Nobel Prize in Physiology in 2012, and for some time, the scientific community (and lots of members outside the scientific community) was ecstatic about the possibilities.
Pluripotent cells created in an artificial environment with absolutely no need to harvest stem cells from embryos or placentas. These are cells that we can transplant so degenerative illnesses can meet their match – a possible solution to Parkinson’s disease, Huntington’s disease, Alzheimer’s disease, and Lou Gehrig’s disease.
However, IPSCs, much like all stem cells transplanted in test subjects, are potentially tumorigenic. Simply put, IPSCs have been shown to cause a special kind of somatic rejection, known in layman terms as the peculiar formation of cancerous tumors.
Researchers Chung et al. published a paper in the journal Cell Stem Cell on April 17, 2014 that described a process in which somatic cell nuclei (the nucleus is the brain of a cell) could be transplanted into oocytes (the egg released during the female reproductive cycle) and manipulated to form embryonic stem cells. The research has yet to show any meaningful results with mature human cells. However, the test subjects transplanted with stem cells have also shown no signs of tumours.
If Chung et al.’s research continues, science may soon come upon a safe method of creating stem cells that avoids the pesky cancer problem.