What Are Stem Cells?
Your first stem cells are formed at conception. They are called totipotent because they give rise to all the cells in the body including the placenta and amniotic sac. In the embryonic and fetal stages, we have pluripotent stem cells that give rise to all the cells of the body.
As we mature so do the stem cells, and they lose the potential to develop into as broad a range of cell types. As adults, many of our stem cells are multipotent. These cells are more limited in the types of cells into which they can develop.
The multipotent stem cells we are most interested in for repair and regeneration are known as mesenchymal stem cells. These multipotent stem cells can divide into a variety of important cells including cartilage, ligaments, tendons, bone, muscle and fat. Robust reservoirs for these cells are in bone marrow.