Biomedical Engineering Reference
In-Depth Information
Chapter 3
Embryonic Stem Cells: Problems
and Possible Solutions
Glory is fleeting, but obscurity is forever.
- Napoleon Bonaparte
Animal models have demonstrated that transplanted embryonic cells are exposed to
the immune reactions similar to those acting on organ transplants, hence immuno-
suppression of the recipient is generally required. It is, however, possible to obtain
embryonic stem cells that are genetically identical to the patient's own cells. The
nucleus from the patient's somatic cell is transferred into an egg after removal of the
egg's own genetic material (a technique known as nuclear transfer or therapeutic
cloning). Under specific condition the egg will use genetic information from the
patient's somatic cell in organizing the formation of a blastocyst which in turn gen-
erates embryonic stem cells. These cells have a genetic composition identical to that
of patient, are suitable for stem cell therapy, will generate patient's own proteins,
and escape the danger for “self-attack” and immune rejection [
1
] .
What is other problem about embryonic stem cells? Stem cells are the primordial
goop of the human body cells that have not yet been differentiated into bone, blood,
or brain cells. For medical researchers, stem cells represent a mother lode of possi-
ble new treatments for diabetes, heart disease, Parkinson's, and more. Capable of
differentiating into the full spectrum of other cell types—from a new liver cell to a
new neuron—they could be ideal for repairing or replacing diseased organs. They
are the basic and critical entity for establishment and development of tissue
engineering.
The furor over stem-cell research is over their source: should researchers use
aborted or discarded human embryos? Or should they be restricted to adult stem
cells, found in fat, bone, the brain, and other sources? Because of ethical problems
only embryos which cannot be used in fertility treatment, and have been donated for
research, can be used, so far. The ethical questions are certainly riveting, but they
may be swiftly trumped by the market, specifically the venture investment market,
which is voting with its dollars for adult stem-cell research. Why? If you look at
