Stem Cells: What, How and Why?
Stem cells are infinitely valuable when considering their
potential applications in the medical profession. While
current legislative restrictions have halted the development of
new ?stem cell lines? to any agency or company that receives
any form of governmental grants, there is no question that the
medical profession is standing at the brink of a new era of
technological advancements in healthcare and research.
Stem cells are valuable due to the fact that they are
?non-designated,? (have no specifically assigned task in the
body, i.e. liver cells, brain cells, skin cells, etc.) and they
also have the ability to divide indefinitely. Thus,
theoretically stem cells could replace any damaged or lost
specifically designated cells within the body.However, this
is just a brief mention of the potential applications of stem
cell research, which will be discussed at a later point in this
Stem cells are categorized into three genres based upon
their potential developmental capability, total to limited.
(NIH PRIMER http://www.nih.gov/news/stemcell/primer.htm)
Totipotent stem cells are stem cells whose potential is
total, thus totipotent. Totipotent stem cells are derived from
embryonic tissue and fertilized ovarian eggs.
This type of stem cell is of particular importance to
researchers due to its ability to ?specialize into
extraembryonic membranes and tissues, the embryo, and all
postembryonic tissues and organs? (NIH Primer). However these
type of cells are extremely difficult to come by and only occur
in certain places at certain developmental times.
Pluripotent stem cells are stem cells in which their
potential is large but not total as in Totipotent stem cells.
These cells lead to the development of many cells, but cannot
derive certain types of fetal cells necessary for the
development of a fetus as do Totipotent stem cells.These
cells undergo further assigment into cells that are designed to
derive specifically assigned cells. Pluripotent stem cells are
somewhat easier to come by comparatively speaking to totipotent
The final genre of stem cells is that of multipotent stem
cells. These cells are more specialized than the other two
categories and thus are more restricted in their capability.
Multipotent stem cells are derived from pluripotent stem
cells.While pluripotent stem cells are least in their
potential capability, they are however the easiest type of stem
cell to acquire. Two methods of acquiring pluripotent stems
cells have been born by two different men.
The first method, developed by Dr. Thomson involves ?the
isolation of pluripotent stem cells directly from the inner
cell mass of human embryos at the blastocyst stage. Dr.
Thomson received embryos from IVF (InVitro Fertilization)
clinics.?.Dr. Thomson isolated the inner cell mass and
cultured these cells producing a pluripotent stem cell line.?
The second method of deriving pluripotent stem cells was
developed by Dr. Gearhart. In this more controversial method,
Gearhart obtained stem cells from the fetal tissue of
terminated pregnancies. He took cells from areas of the fetus
that would soon develop into the reproductive organs of the
fetus.He then isolated the inner cell mass and cultured
these cells. In was in this way that Dr. Gearhart produced a
pluripotent stem cell line which would be available to other
What little we know about stem cells has already altered the
course of medical research and new findings are sure to expand
on this occurrence. The potential applications of stem cell
research include advancements in the study of Parkinson?s,
Alzheimer?s, spinal cord damage, stroke, burn victims and
patients in need of skin grafts, heart disease, diabetes and
arthritis in addition to answering some of the many questions
regarding gene therapy.
So what?s the problem? Well, the NIH (National Institutes
of Health) issued a ?primer? to explain what exactly are stem
cells and what is the debate. While this primer was my only
source for this essay, it did neglect to discuss certain
governmental issues, which revolve around the issue at hand.
Most likely this can be attributed to the obvious, the NIH is a
governmental agency. This is a precise example of why the
issue of stem cell research is being called into question. Off
course, ethics is at the bottom of the debate,