As we has already discuss before, that stem cells devided into two types, which is embryonic stem cells and adult stem cells, the Embryonic stem cells come from pluripotent cells, pluripotent embryonic stem cells exist only at the earliest stages of embryonic development. In humans, these cells no longer exist after about five days of development. When isolated from the embryo and grown in a lab dish, pluripotent cells can continue dividing indefinitely. These cells are known as embryonic stem cells.
Pluripotent stem cells have the potential to differentiate into almost any cell in the body, this means that under the right circumstances, a stem cell that is isolated from an embryo can produce almost all of the cells in the body. After this embryonic development stage is over, the stem cells no longer have this unlimited potential to develop into all cell types, their pluripotency is thus lost and they can only become certain types of cells.
What Makes a Stem Cell Pluripotent?
Better for all us to remind again how is the human body in the very early stages of development
After an egg is fertilised by a sperm, a single cell results. This cell is totipotent – has the potential to create an entire organism. In the initial hours and days following fertilisation, this single totipotent cell divides into more totipotent cells that are exact copies of the original.
Approximately four days after fertilisation, the totipotent cells start to specialise and form a cluster of cells known as a blastocyst. The blastocyst has yet another smaller group of cells known as the inner cell mass and it is these inner pluripotent stem cells that will go on to create most of the cells and tissues in the human body.
These pluripotent stem cells are therefore different than totipotent stem cells because they don’t develop into a complete organism. As such, a pluripotent cell won’t give rise to the placenta or other tissues that are vital for foetal development. It will still develop into the other specialised cell types in the human body, such as nerve or heart cells.