Stem cells have key features that separate them from other types of cells. They are unspecialised, meaning they have not developed into cells that perform a specific function. They can differentiate, meaning they can divide through the process of mitosis and produce daughter cells that have the potential to become other more specific cell types, tissues or organs (such as blood cells, brain cells, heart muscle or bone). No other cell in the body has the natural ability to generate new cell types. These new cells and tissues are used to repair or replace damaged or diseased cells in the body. Lastly stem cells are able to divide and produce copies of themselves which leads to self-renewal. However once a stem cell has become specialised (differentiated) to a particular tissue or organ, it has a very limited capacity to self- renew (produce new stem cells) but instead produces only cells relevant to that organ.
The stem cells are a break through in medical perspective because for decades, researchers have been studying the biology of stem cells to figure out how development works and to find new ways of treating health problems. And stem cells can give rise to any tissue found in the body, they provide nearly limitless potential for medical applications.
Stem cells can be used to study development, it may help us understand how a complex organism develops from a fertilised egg. In the laboratory, scientists can follow stem cells as they divide and become increasingly specialized, making skin, bone, brain, and other cell types. Identifying the signals and mechanisms that determine whether a stem cell chooses to carry on replicating itself or differentiate into a specialized cell type, and into which cell type.
Stem cells have the ability to replace damaged cells and treat disease. For example, burn victims tend to endure an enormous amount of pain from their wounds as well as frustration from the challenges of healing. Instead of donor tissues being donated, stem cells could be used to produce new and healthy tissues.
By directing stem cells to differentiate into specialised cell types, there is the exciting possibility to provide a renewable source of replacement cells for those suffering from diseases. Current studies are researching how stem cells may be used to prevent or cure diseases and injuries such as Parkinson’s disease, type 1 diabetes, heart disease, spinal cord injury, Duchene’s muscular dystrophy, Alzheimer’s disease, strokes, osteoarthritis, rheumatoid arthritis, hearing loss and many more. (Refer more to the diagram on the right)
Stem cells are found in the early embryo, the foetus, amniotic fluid, the placenta and umbilical cord blood. After birth and for the rest of life, stem cells continue to reside in many sites of the body, including skin, hair follicles, bone marrow and blood, brain and spinal cord, the lining of the nose, gut, lung, joint fluid, muscle, fat, and menstrual blood, to name a few.
The three main technologies in use today to extract those stem cells are:
Bone marrow stem cells, where the patient's bone marrow stem cells are replaced with those from a healthy, matching donor. If the transplant is successful, the stem cells will migrate into the patient's bone marrow and begin producing new, healthy leukocytes to replace the