By Emmanuella Umoye
You may associate the word stem with plants and roots, but we’ve got STEM CELLS in our bodies too (and it's very dissimilar to what it’s known for in plants). Stem cells are basic materials through which specialized cells, tissues, or organs are formed. Stem cells divide into new cells that are either specialized in function or new stem cells. Some examples include neural stem cells, epithelial stem cells, and skin stem cells. Furthermore, stem cells are obtained from these sources:
1. Embryonic Stem Cells (ESCs): These are stem cells that grow within the first 3-5 days of an embryo. They’re called pluripotent because they can divide into new stem cells or specialize into various cells in the body. They’re usually about 150 of them in an embryo. Due to their ability to specialize in various cells, they’re especially useful in fixing injured tissue.
2. Adult Stem Cells (ASCs): They are a cluster of cells found within adult parts of the body like the gut, bone marrow, skeletal muscle, and brain. The adult stem cells grow and regenerate throughout a person’s life. Adult stem cells can divide or self-renew indefinitely. This means they can generate various cell types from the originating organ or even regenerate the original organ, entirely. This division and regeneration are how a skin wound heals, or how an organ such as the liver, for example, can repair itself after damage.
3. Induced Pluripotent Stem (IPS) Cells: These cells are a cross of both adult stem features and the Embryonic Stem Cells. Scientists genetically program induced pluripotent stem cells, which are a type of pluripotent stem cells derived from adult somatic cells. They have been reprogrammed by inducing genes and factors to be pluripotent. IPS cells are similar to embryonic stem (ES) cells in many aspects. IPS cells are created through the introduction of embryonic genes into a somatic cell (a skin cell for example) that cause it to revert back to a “stem cell-like” state through the forced expression of genes and factors important for maintaining the defining properties of ES cells. The breakthrough of IPS cells allows researchers to obtain pluripotent stem cells without the controversial use of embryos. Moreover, tissues derived from IPS cells will be a nearly identical match to the cell donor, which is an important factor in the research of disease modeling and drug testing. Scientists are certain that IPS cells will help researchers learn how to genetically reprogram cells to repair damaged tissues in the human body.
4. Perinatal stem cells(PSCs): These stem cells are found in the amniotic fluid and sac surrounding a woman’s womb. They were discovered by studying the amniotic fluid obtained from a pregnant woman. More research is being conducted on how they can be used.
Uses of stem cells
1. Research on the development of disease in humans: The metamorphosis of stem cells in a cultured environment can be used to monitor the development and growth of the disease in places such as the bones, bone marrow, and brain.
2. Regenerative medicine: stem cells can be guided to become specialized cells. Through this process, they can also specialize in entire new organs and replace/heal damaged tissues or organs. Regenerative medicine is useful in the treatment of neurodegenerative diseases such as Parkinson’s, Amyotrophic Lateral Sclerosis (Lou Gehrig’s), and Alzheimer’s.
3. Tissue regeneration: Scientists can manipulate stem cells to specialize into healthy tissues or organs. By using stem cells, there is a reduced need for organ transplants which are already quite scarce and a person gets the treatment they need.
4. Test for new drugs: When cells are developed as special ones, they can be used to test if certain drugs will affect their specialization before testing it on an actual human. As a nerve cell can be used to detect the impact of a nerve drug for nerve disease. This prevents complications that may arise if they’re directly used on patients.
Every day, more advancement is made in the study of what stem cells can achieve in the human body. Recently, it has been discovered that adult stem cells, albeit limitedly, are able to specialize into a variety of cells that aren’t located where the adult stem cells originate from such as stem cells in the bone marrow forming specialized brain cells. However, due to ethical reasons, there are limitations on the use of stem cells. For embryonic stem cells, they are usually obtained by the donation of embryos in IVF houses that failed to fertilize. Adult stem cells are usually donated by volunteers or even patients seeking treatment for monitoring and testing.
Questions
1. What are stem cells?
Stem Cells are the raw materials that give rise to new stem cells or specialized cells, tissues, and organs. They range from bone marrow cells to muscle cells. They are also used at times for the repair of damaged tissue.
2. What are the sources of stem cells?
Stem Cells arise from three sources, Embryonic Stem(ES) Cells, Adult Stem(AS) Cells, Induced Pluripotent Stem(IPS) Cells, and Perinatal Stem Cells(PS).
Article Credit:
Mayo Clinic: https://www.mayoclinic.org/tests-procedures/bone-marrow-transplant/in-depth/stem-cells/art-20048117
MedicalNewsToday: https://www.medicalnewstoday.com/articles/323343
UNMC: https://www.unmc.edu/stemcells/educational-resources/types.html
Image Credit
Flickr: https://flic.kr/p/akiAA6, License: Creative Commons Legal Code