What are the Three Types of Stem Cells?
Through continued research and discovering, the use of stem cells has been a consistent factor in treating and understanding diseases within the human body. While most cells in our body are differentiated, meaning they mostly serve few specific purposes in particular organs, stem cells are undifferentiated, or “blank,” making them capable of developing into various functional cells. When the human body first starts to develop, there is only one cell known as a zygote, or fertilized egg. Then this egg begins to divide into two cells, then four, and so on. Naturally, the cells begin to differentiate and take on the role of helping to grow and maintain function in various parts of the body. Stem cells are those that have not differentiated yet or chosen a specific function.
Stem cells effectively aide in correcting parts of organs that aren’t working properly, as well as to grow new cells to replace damaged organs and tissues. Stem cell therapy has been used for years to treat and regenerate function from diseases and issues stemming from spinal cord injuries, type 1 diabetes, Parkinson’s disease, Erectile Dysfunction, heart disease, stroke, burns, cancer and osteoarthritis, among others. But what types of stem cells are there being used in medicine right now?
Adult Stem Cells (ASCs)
Adult, or somatic stem cells, derive from developed organs and tissues that have the ability to renew and generate new cells to replenish dead or damaged tissue in the body. These cells are limited to the number of times they can differentiate, unlike embryonic cells and are typically scarce in native tissues, making them difficult to study and extract for research purposes. ASCs are generally found in tissues such as the umbilical cord, placenta, bone marrow, muscle, brain, fat tissue, skin and gut. Types of adult stem cells include:
- Hematopoietic Stem Cells (Blood)
- Mesenchymal Stem Cells
- Neural Stem Cells
- Epithelial Stem Cells
- Skin Stem Cells
Embryonic Stem Cells (ESCs)
Embryonic Stem Cells derive from human embryos 3-5 days following a fertilization process called In-Vitro, meaning they are fertilized in a lab versus a body. During this timeframe, the embryo contains an inner cell mass capable of generating all the specialized tissues that make up the human body. Because these pluripotent cells are derived in that 3-5 day window, they have the potential to become just about any cell type, making them ideal for research and discovery.
Induced Pluripotent Stem Cells (iPSCs)
iPSCs are a happy medium between embryonic and adult stem cells and are created in a lab versus found in the body using a process that genetically reprograms adult stem cells so that they behave like embryonic stem cells. And reverted back to pluripotent cells means they have the potential to produce new cells for any organ or tissue. While this process is still in its research stage and not available for clinical trials just yet, it’s opening up an entirely new avenue to understanding how diseases develop. Recent studies suggest the cells could be made from someone’s own skin to treat a disease, which would prevent the immune system from rejecting an organ transplant.