Transcript Stem Cells
Stem Cells: Miracle
Cure?
Avionna Baldwin
J. Onyi Oradiegwu
SAMS 2008
What is Tissue Engineering/
Regenerative Medicine?
Replacing diseased or injured
tissues with tissue constructs
designed and fabricated for the
specific needs of each individual
patient.
What are
Biomaterials?
A material intended to interface
with biological systems to
evaluate, treat, augment or
replace any tissue, organ or
function in the body.
Still thousands die while waiting for a transplant, and
thousands more aren’t even on the list.
400 bil: ½ of
national
health care
bill goes to
patients with
organ failure,
or tissue loss
Five hottest jobs for the
next millennium will be
bioengineering/biomedical
related.
Tissue
Engineering
Hottest job for 21st
Century
No One Discipline Can Tackle
the Problem Alone
Lee Weiss, Carnegie Mellon
Normal Wound Repair
Requires a Balance of
Processes
The Basic Three Rs
of Tissue Engineering
Right
Hormones
Matrices
Right
ECM
Cells
Healing
Signaling
Molecules
Right
Cells
Guided Tissue Repair
If needed, harvest cells
from patient.
Biomimetic
extracellular
matrix
Lee Weiss, Carnegie Mellon
Culture
Implant
Principles of Tissue Engineering
Cells
ECM
Defect
Hormones
Phil Campbell, Carnegie Mellon
Regeneration
Blood
Supply
What about the cells?
Adult stem cells
look promising
for some applications
Embryonic stem cells
great potential,
controversial
The right hormones can
induce
these cells to become
a variety of cell types
• A cell that is able to differentiate into
many cell types is known as pluripotent
– Can’t grow into a totally new indiv.
Because they don’t make extraembryonic
structures like placenta
• A cell that is able to differentiate into all
cell types is known as totipotent.
– Can go full on into a new indiv. They can
make a placenta
– Amazing: plants are way easier to find
totipotent cells in
Beast boy can
turn into any
animal
adipocyte
osteoblast
hematopoetic/endothelial
cells
muscle cell
chondrocyte
Adult MuscleDerived Stem Cells
(MDSCs)
nerve cells/neurons/glial cell
hepatocyte/urinary bladder cells
Pancreatic islets??
Derivation of Human Embryonic Stem Cells
(hESC’s)
http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf
Derivation of Human Embryonic Stem Cells
(hESC’s)
http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf
Modified Cell Stem Cell Induction or
Derivation.
http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf
http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf
Adult Stem Cell Derivation
Stem Cell Differentiation
Princeton University
Stem Cell Cultivation
University of Wisconsin-Madison
Human Stem Cell Production
Tissue origins
• Embryonic cells
present molecules
on their
membranes that
aid in the early
organizing process
– Ectoderm,
mesoderm,
endoderm
You’ve got stem cells in you right now
• Note: Progenitor cells: a term like stem
cells, but less restrictive
• Adults have stem cells in blood
marrow.
– They’re multipotent, but not pluripotent
– Might have suffered ravages of time,
sunlight, and toxins, that come with aging
• There are also stem cells in umbilical
cords
• Embryonic stem cells = controversy
Bo is like a
pluripotent athlete.
An Ultimate Vision for Regenerative
Medicine: Complete Tissue Regeneration
Spinal Cord
Retina and Lens
Tail
Upper and
Lower Jaw
Heart
Limb
The Newt
From Dr. Susan Bryant,
Univ.from
of Calif.,
Irvine
Adapted
Brockes
Phil Campbell, Carnegie Mellon
And lots of tissue engineering research
looks very promising
For example,
tissue-engineered nerve guides
for treatment of spinal cord injuries
• After induced put in the video and see the clip
to implement the stem cell
Medical Implants
Millions of People in the US
Have Medical Implants
Associated with
a $50 billion/year
Medical Device Industry
FDA approved products
Infuse Bone Graft
Bone morphogenetic protein-7,
Osteogenic peptide-1
Regranex
Carticel
Transcyte
Intergra Dermal Regeneration Template
Dermagraft
Apligraft
Ortec
Short form: Know the argument
• Proponents
– They’re from embryos that are slated for destruction
anyway
– Great potential for good
– Superman was for it
• Only for embryoes that were
going to be discarded
• Opponents
– Destroys embryos
– Devalues worth of human
•Hot research area: harvest embryonic
stem cells without destroying the embryo.
Proponents Argument in depth
– Embryonic stem cells are more useful
– Utilitarian
• The benefits of stem cell research outweigh the cost in
terms of embryonic "life“
– human potential vs humanity
• The value of an embryo should not be placed on par
with the value of a child or adult
• Life starts with a heartbeat
– Ends justify the means
– Efficiency
• If an embryo is going to be destroyed anyway, isn't it
more efficient to make practical use of it?
• In Vitro Fertilization makes thousands of unusable
embryos
Opponents
arguments in
depth
– Embryos are lives
• Life starts at conception
• Note Roe v. Wade said life = viability, ability to survive
outside of womb, medical advancements have pushed
this back to 22 weeks. Could trend continue?
– Exploring alternative therapeutic options
• We’ve studied adult stem cells longer and have more
therapies with them that with embryonic
– The potential is overstated
Legal
Sweden
Finland
Belgium
Greece
the United Kingdom,
Denmark
Netherlands
China
Japan
Korea
Taiwan
Israel
Iran
Illegal
Germany
Austria
Ireland
Italy
Portugal.
Most of middle east
Africa, except S. Africa
S. America, except Brazil