Transcript Using Stem Cells

Using Stem Cells
• A stem cell is a cell that can continuously divide and
differentiate into various tissues.
• Some stem cells have more potential to differentiate
than others.
• Adults’ bodies have some multipotent cells that can
be removed, frozen or cultured, and used for medical
treatments.
• The cells of new embryos have more potential uses.
• The use of embryos for stem cell research poses
ethical problems.
• An alternative source of embryonic stem cells is
through SCNT (somatic cell nuclear transplant).
What are Stem Cells?
Stem Cells are extraordinary because:
• They can divide and make identical
copies of themselves over and over
again (Self-Renewal)
• Remain Unspecialized with no
‘specific’ function or become . . . .
• Specialized (Differentiated) w/ the
potential to produce over 200 different
types of cells in the body.
The Major Types of Stem Cells
A. Embryonic Stem Cells
• From blastocysts left over from In-Vitro
Fertilization in the laboratory
• From aborted fetuses
B. Adult Stem Cells
• Stem cells have been found in the blood,
bone marrow, liver, kidney, cornea, dental
pulp, umbilical cord, brain, skin, muscle,
salivary gland . . . .
http://commons.wikimedia.org/wiki/Image:Stem_cells_diagram.png
Advantages and Disadvantages to
Embryonic and Adult Stem Cells.
Embryonic S.C.
Adult S.C.
“Pluripotent”
(can become any cell)
“Multipotent”
(“can become many but
not any”)
Less Stable. Capacity for
self-renewal is limited.
Difficult to isolate in adult
tissue.
Stable. Can undergo
many cell divisions.
Easy to obtain but
blastocyst is destroyed.
Possibility of rejection?? Host rejection minimized
http://www.pbs.org/newshour/bb/science/jan-june14/stemcells_01-29.html
Reprinted with permission of Do No Harm. Click on image for link to website.
• http://www.youtube.com/watch?v=7QlWBnL
0zjU
Why is Stem Cell Research So Important to All of Us?
Stem cells allow us to study how
organisms grow and develop over time.
Stem cells can replace diseased or
damaged cells that can not heal or
renew themselves.
We can test different substances (drugs
and chemicals) on stem cells.
We can get a better understanding of
our “genetic machinery.”
What Human Diseases are Currently Being
Treated with Stem Cells?
• Parkinson’s Disease
• Leukemia (Bone Marrow Transplants)
• Skin Grafts resulting from severe burns
Stem Cell Therapy has the Potential to:
• Regenerate tissues/organs
• Cure diseases like diabetes, multiple
sclerosis, etc.
Why the Controversy Over Stem cells?
• Embryonic Stem cells are derived from
extra blastocysts that would otherwise
be discarded following IVF.
• Extracting stem cells destroys the
developing blastocyst (embryo).
-Questions for ConsiderationIs an embryo a person?
Is it morally acceptable to use embryos
for research?
When do we become “human beings?”
Key Concept Questions
• How are transgenic organisms useful to human
beings?
– Genetic engineering has spurred the growth of
biotechnology, a new industry that is changing
the way we interact with the living world
• How are cloning and stem cell research related?
– Cloning can produce organisms that are
genetically identical to preexisting individuals.
Stem cells can be used to grow new tissues.