Embryonic stem cells (ESCs) are pluripotent cells that can differentiate into any cell type in the body. This makes them a promising source of cells for regenerative medicine, the field of medicine that aims to repair or replace damaged tissues and organs. ESCs are derived from the inner cell mass (ICM) of blastocysts, which are early-stage embryos.
The Source of Embryonic Stem Cells
ESCs are derived from the inner cell mass (ICM) of blastocysts, which are early-stage embryos. The ICM is the part of the blastocyst that will eventually give rise to the fetus. ESCs can also be derived from the epiblast, which is the layer of cells that gives rise to the embryo proper.
Harvesting Embryonic Stem Cells
ESCs can be harvested from blastocysts that are donated by couples who have undergone in vitro fertilization (IVF). After the IVF procedure, the fertilized eggs are cultured in the laboratory until they reach the blastocyst stage. The blastocysts are then screened for genetic abnormalities, and those that are found to be normal are used to derive ESCs.
ESCs can also be derived from embryos that are created through somatic cell nuclear transfer (SCNT). In SCNT, the nucleus of a somatic cell (a cell from the body) is transferred into an enucleated egg cell (an egg cell that has had its nucleus removed). The egg cell is then fertilized, and the resulting embryo is cultured until it reaches the blastocyst stage. ESCs can then be derived from the ICM of the blastocyst.
ESCs are a promising source of cells for regenerative medicine. However, the use of ESCs is controversial because it requires the destruction of embryos. As a result, there is a great deal of interest in developing alternative sources of pluripotent stem cells, such as induced pluripotent stem cells (iPSCs). iPSCs are generated by reprogramming adult cells into a pluripotent state. This process does not require the destruction of embryos, and it could provide a more ethical and sustainable source of pluripotent stem cells for regenerative medicine.
