Stem cells are the foundation cells in the human body, which can differentiate via mitosis and depending on the environment and growth factors, produce different kinds of cells and are hence pluripotent. In mammals, there are two basic types of stem cells – the embryonic stem cells, and the adult stem cells. The embryonic stem cells are obtained from the blastocysts of the embryo, while the adult stem cells are found in different tissues throughout the body. Embryonic stem cells are pluripotent, while adult stem cells are not generally pluripotent, but mostly multipotent, oligopotent or even unipotent (that is the reducing order of ability for it to form different cells). Stem cells can be cultured to produce complete organs for a human being using specific growth factors and hence therapies involving embryonic stem cell lines are being researched. The animation below describes the process of how embryonic stem cell lines are made from the blastocyst.
Use of embryonic stem cells in research has been hotly debated for several years. This animation presents the basics on how stem cell lines are established.
Embryonic stem cells are derived from blastocysts-embryos that are about a week old. At this stage, the blastocyst has about 100 cells. Human blastocysts like this have been donated to research from in vitro fertilisation clinics.
In order to get embryonic stem cell lines, scientists remove cells from the inner cell mass region. These cells have the potential to develop into any type of cell in the body.
Once the cells are removed, they are placed on a culture plate with nutrients and growth factors. The blastocyst is destroyed in this process.
An embryonic line is established when these cells multiply and divide. Under the right conditions, these cell lines can be maintained indefinitely.
By adding different growth factors, it is possible to induce these embryonic stem cells into developing into different cell types.
These cells could someday be used in therapies to replace damaged cells and organs.