Stem cells come from all kinds of organisms. To better understand the origin of the stem cell, Scientists have categorized different types of stem cells in distinct ways. These categories can tell us the sources of stem cells, their potency, and their differentiation abilities. Below, we have prepared a guide for you, so that you can learn more about the many stem cell types. Read on to know more.
A Guide to the Different Types of Stem Cells
Types According to Potency
One must understand the concept of cell differentiation to fully grasp what cell potency is. Differentiation is the process by which a cell transforms into a more specialized one. The potency of stem cells refers to the number of differentiations or specializations they can undergo. Furthermore, a cell’s potency tells us how many kinds of specialized cells a stem cell can transform into.
1. Totipotent Stem Cells
— Erin Hamilton Spence (@mommamdfw) April 6, 2017
These kinds of stem cells can differentiate into any kind of cell in the body. During fertilization, the sperm and egg cells yield a zygote. This initial stage of the embryo then divides itself into countless cells of different forms that serve as precursors to all the cells that make up the human body. Therefore, totipotent stem cells are the most versatile kind of stem cell.
2. Pluripotent Stem Cells
— Parkinson’s People (@ParkinsonPeople) September 4, 2017
After a zygote’s 4 days of total potency (totipotency), it will undergo further divisions. Thereafter, its stem cells will become more specialized. These stem cells are called pluripotent. Pluripotent stem cells can differentiate into a variety of cell types but not all types.
3. Multipotent Stem Cells
Consider multipotent stem cells a level lower than pluripotent stem cells in the potency hierarchy. While they can transform into more than one type of cell, they’re more limited than the other two categories mentioned above.
4. Unipotent Stem Cells
As its name suggests, unipotent stem cells can differentiate to only one lineage. These cells have the lowest potency.
Types According to Source
Another way of categorizing stem cells is by their origin or source. Because stem cell types overlap, you should familiarize yourself with the potency types. That way, the different types of stem cells below will remain clear.
A. Adult Type Specific Stem Cells
Adult type specific stem cells are undifferentiated cells found among specialized cells in tissues or organs after birth.
1. Umbilical Cord Stem Cells
What many would regard as biological waste actually has the potential for stem cell therapy. In fact, the umbilical cord contains stem cells that can be cultured to become every type of cell in the blood.
2. Umbilical Blood Stem Cells
Similar to the umbilical cord, residual blood from the cord after a baby is born also contains stems cells. Surprisingly, there have also been reports that cord blood carries stem cells that can differentiate into other types of cells, like nerve cells.
3. Placental Stem Cells
— Hudson Institute (@Hudson_Research) May 26, 2017
Aside from the umbilical cord and blood, there also are stem cells that can be harvested from the placenta. Currently, there are over 50 clinical trials studying therapeutic capabilities of placental stem cells. Scientists are currently applying these stem cells to research on Type 1 diabetes, Alzheimer’s, and spinal cord injuries.
4. Amniotic Fluid Stem Cells
These stem cells are extracted from the amniotic fluid and the amniotic membrane of the placenta. They can differentiate into the following cell and tissue types: skin, cartilage, cardiac tissue, nerves, muscle, and bone.
5. Gastric Epithelial Stem Cells
These stem cells are closely linked to gastric cancer. Scientists regard the disease as a result of dysregulated differentiation of stem and progenitor cells in the intestines.
6. Heart Stem Cells
These multipoint stem, or progenitor, cells found in the hearts of mammals can self-renew and generate coronary vessels and heart muscle cells known as cardiomyocytes.
7. Neural Stem Cells
Neural stem cells are multipotent cells that can differentiate into neurons and glia of the nervous system. As with other stem cells, they are self-renewing.
8. Hepatic Stem Cells
Doctors understand that our livers have “regenerative capabilities.” This is because of the presence of stem cells. According to this study, significant clonal expansion of a certain proportion of liver cells in liver transplants in animals suggests that liver cells are functional stem cells of the organ.
9. Epidermal Stem Cells
Epidermal, or skin, stem cells are multipotent adult stem cells found in our skin. These stem cells are active during skin renewal. Currently, scientists use these stem cells to grow skin for burn victims.
10. Adipose Stem Cells
These are stem cells that are isolated from fat tissues. They can differentiate into bone cells and cartilages.
11. Bone Marrow Stem Cells
Stem cells found in the bone marrow can give rise to different blood cell types. Doctors use these stem cells for treating blood-related diseases like leukemia or some types of lymphoma.
B. Embryonic Stem Cells
Unlike adult stem cells, which can differentiate into more specialized cells, embryonic stem cells are pluripotent.
1. Embryonic Stem Cells
Global Human Embryonic Stem Cells Market – Growth, Trends and Forecasts (2017 – 2022) https://t.co/X8czF3oAXx
— Tanya Syaroff (@TanyaSyaroff) October 27, 2017
These are usually harvested from embryos that are 5-7 years old. These types of stem cells are subject to ethical and moral issues, because embryonic stem cells are usually harvested from embryos that would otherwise be discarded by fertility clinics.
2. Embryonic Germ Cells
Scientists obtain these stem cells from miscarried or aborted fetuses.
C. Induced Pluripotent Stem Cells
As evident from their name, induced pluripotent stem cells are stem cells genetically reprogrammed to have the pluripotency possessed by embryonic stem cells. Scientists currently use them for drug development and modeling of diseases.
Types According to Differentiating Capabilities
Finally, we can also categorize stem cells by the kinds of cells they can differentiate into.
1. Hematopoietic Stem Cells (HSC)
— 魅力無錫 Wuxi China (@WuxiCity) August 24, 2017
Hematopoietic stem cells can differentiate into all types of blood cells. For example, stem cells found in adult bone marrow and umbilical cord blood are HSCs.
2. Mesenchymal Stem Cells (MSC)
— Gorka Orive, PhD (@gorka_orive) September 27, 2017
Mesenchymal stem cells are multipotent stem cells capable of differentiating into bone cells, cartilage cells, muscle cells, and fat cells.
Watch the video below for the different types of stem cells and what are they used for:
Contrary to popular belief, stem cells don’t just come from fetuses. They come from all kinds of organisms, animals, humans, body parts and are used for distinctive procedures. Finding different sources and uses for stem cells could be the breakthrough to finding cures for the world’s most seemingly un-treatable diseases. Don’t worry, we’ll stay on top of it!
Did you find this guide informative? Let us know in the comments section below!