What Are Stem Cells and Why Are They Important?
Understanding the different types of stem cells and their role in research.
In the past few years, stem cells, and the controversy surrounding them, have made their way into the mainstream media. However, many don’t have a clear understanding of what stems cells are and the different ways that stem cells can be obtained.
Stem cells are "building block" cells that can develop into any kind of cell in the human body. They have the ability to renew or replicate themselves through simple cell division, creating millions of new cells for the life of the individual. Together, these two traits make stem cells remarkably valuable because they can, potentially, replace diseased or damaged cells to cure people with illnesses or repair damage caused by the illness.
There commonly discussed forms of human stem cells are, adult stem cells and embryonic stem cells.
What are adult stem cells?
An adult stem cell is a non-specialized cell found among cells in a tissue or organ. Every person has stem cells within their organs and tissues. The stem cell can renew itself, and evolve into the major specialized cell types of the tissue or organ. The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found.
Adult stem cells are generally limited to differentiating/specializing into different cell types of their tissue of origin. However, some evidence suggests that adult stem cells may have more capabilities of differentiation than previously thought, increasing the number of cell types a given adult stem cell can become. Currently bone marrow donations and umbilical cord blood are the key sources of adult stem cells.
What are embryonic stem cells?
As their name suggests, embryonic stem cells come from embryos. They typically come from embryos that develop from eggs fertilized in vitro—in an in vitro fertilization clinic—and then donated for research purposes with informed consent of the donors. They are not derived from eggs fertilized in a woman's body. Human embryonic stem cells are typically derived from discarded 4-5 day old embryos (i.e. when a couple no longer has a need for their embryos and request that they be used for creating ES cell lines.) Only embryonic stem cells can become all cell types of the body because they are completely unspecialized.
The Debate
The controversy that is typically highlighted in stem cell research surrounds embryonic stem cells. The use of adult and cord blood stem cells in research, and in the treatment of patients has been done for decades and is not a controversial topic.
Children's Cancer Research Fund believes great promise exists within stem cell research. Support from our organization has only funded adult and cord blood stem cell research. Progress in this area has made a dramatic and positive impact on survival rates for both children and adults.
