Essentially all of the Cells of aDeveloping Embryo are Stem Cells

Embryonic stem cells are derived from embryos before to the 2nd week of development long before the developing embryo has transitioned to becoming a Fetus. During these first two weeks, essentially all of the cells of the embryo are stem cells, in that they have not differentiated into cells with specialized functions. Typically embryonic stem cells are derived from embryos that are created in laboratory conditions, not harvested directly from a human mother. In other words, a human egg has been harvested from a woman and fertilized with a human sperm in vitro (in a laboratory). Thus usually takes place in an in vitro fertilization clinicand then donated for research purposes.

The technique of growing cells in the laboratory is referred to as cell culture. Human embryonic stem cells (hESCs) are grown by harvesting the cells derived from an early stage preimplantation embryo (a very young embryo that if present in a human mother would not yet be implanted in her uterus). These cells are grown in a special laboratory dish that contains a nutrient broth known as culture medium.

Once the cells have taken hold and are surviving they can be removed and placed into several additional culture dishes. The process is called sub-culturing the cells and can be repeated many times over many weeks and months. Each cycle of sub-culturing the cells is referred to as a passage, and is a way that a few original stem cells can be expanded into many generations and millions of stem cells and are referred to as an embryonic stem cell line.

During the process of generating lines of embryonic stem cells in laboratory conditions, it is important to test the cells to see if they exhibit the basic properties or characteristics of stems cells. This process is called characterization.

Though this process has not been standardized throughout the cell-biology industry, the following are some of the tests that are commonly performed:

Perhaps an even better question to ask is how do we induce stem cells to differentiate into the exact tissue or organ we need?

Let me explain. Obviously, the holy grail of regenerative medicine and stem cell therapy would be to grow a new organ lets say a liver for a patient who has a diseased liver. In such a world, any damaged or diseased organ could simply be replaced by a new young organ generated right from the patients own stem cells.

The hope is that by changing the composition of the nutrient base in which the cells are cultivated, or by adding certain transcription factors, or by using any number of chemical, biochemical and electronic elements, we might find the correct recipe for inducing a stem cell to differentiate into the cells we need or want. Though we have discovered some basic protocols for limited induction of stem cells into specific organ tissues, we are far from growing a complete and viable human organ.

To date our best hope is focusing on developing a specific cell type and not the entire organ. For example the cells that produce insulin within a pancreas, but not the entire pancreas.

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What are Embryonic Stem Cells? - amaskincare.com