What is the difference between totipotent and pluripotent stem cells?

Totipotent stem cells can differentiate into any type of cell, including placental cells, while pluripotent stem cells can differentiate into any type of body cell.

Totipotent stem cells are the earliest form of stem cells, found in the zygote and the first few cells after fertilization. They have the ability to differentiate into any type of cell in the body, including the placental cells that support the developing embryo. This means that totipotent stem cells have the potential to give rise to a complete organism.

Pluripotent stem cells, on the other hand, are slightly more restricted in their differentiation potential. They can differentiate into any type of body cell, but not placental cells. Pluripotent stem cells are found in the inner cell mass of the blastocyst, which is a hollow ball of cells that forms a few days after fertilization. These cells have the potential to give rise to all the cells in the body, but not the placenta.

Both totipotent and pluripotent stem cells have the ability to self-renew, meaning they can divide and produce more stem cells. This makes them valuable tools for research and regenerative medicine. However, the use of totipotent stem cells is more controversial due to their potential to form a complete organism, which raises ethical concerns.

In summary, totipotent stem cells have the ability to differentiate into any type of cell, including placental cells, while pluripotent stem cells can differentiate into any type of body cell but not placental cells. Both types of stem cells have the ability to self-renew, making them valuable tools for research and regenerative medicine.