The document summarizes information from a presentation on stem cells given by Zach Jarou. It discusses the types of stem cells, including embryonic and adult stem cells. Embryonic stem cells are pluripotent and can indefinitely divide and grow, while adult stem cells are multipotent and have a limited lifespan. The presentation outlines the scientific and medical benefits of stem cell research, but notes that not all stem cells are equal in their potential.

1. Zach Jarou
Undergraduate Bioethics Society
Michigan State University
Wednesday, October 24th, 2007

2. Meetings are Alternate Tuesdays
7:30pm in 1420 BPS
to learn more, visit:
www.msu.edu/~ubs
or
Facebook

3. About Me
 BS Chair
U
 hysiology major
P
 esearch experience
R
 rotein-ligand docking (drug design)
P
 tem cells
S
 ioSci Undergrad Lab TA
B
 lso, Botany Greenhouse Volunteer &
A
CNS DSAC

4. Life Exists at Many Levels
• atoms ==> molecules ==> macromolecules ==>
• organelles ==> cells ==> tissues ==>
• organs ==> systems ==>
• organisms ==> populations ==> communities ==>
• ecosystems ==> biomes ==> biosphere
but where does “life” begin?

5. Cellular Basis of Humans
 10 trillion cells
~
in human body
 00+ distinct
2
cell types
 tructure ==>
s
where do all of these
unique cells come from? function

6. Basics of Stem Cells

7. Scientific/Medical Benefits
 eplace damaged cells/tissues/organs
r
 eta-pancreatic cells (type I diabetes)
b
 opamine secreting neurons (Parkinsons)
d
 pinal cord (paralysis)
s
 yelin sheaths (multiple sclerosis)
m
 ornea (blindness)
C
 nderstanding basis of cell development
u
could prevent birth defects
 rug testing/development
d

8. But, Not all Stem Cells are
Created Equal
 otency
P
 mbryonic = pluripotent
e
 dult = multipotent
a
 ifespan
L
 mbryonic = divide & grow indefinitely
e
 dult = limited
a

9. Embryonic Stem Cells
 uring in vitro fertilization,
D
egg + sperm + petri dish + 5 days ==> blastocyst
 hollow ball of
70-100 cells
(smaller than grain
of sand), inner cell
mass can be
harvested
 f implanted into
i
uterus…

10. …it will become a fetus
 efined as fetus after
D
8 weeks
 ide note: neural
s
activity/heart beat
does not begin until
the 6th week of
development

11. Adult Stem Cells
 ene deactivation
g
==> less potentcy
 issue-specific;
t
within bone
marrow:
 ematopoietic ==>
h
blood cells
 esenchymal ==>
m
bone, fat,
cartilage, muscle

12. Cloning (Nuclear Transfer)
 ucleus of adult body cell used to replace
n
egg cell nucleus, creating genetically
compatible embyronic stem cells
 herapeutic - blastocyst used as stem cell
t
source, immunosupressive drugs not required for
transplant
 eproductive - blastocyst implanted into fetus
r

13. My Personal Views
 on’t consider harvesting ESCs from
d
blastocyst to be taking life
 ouble-edge sword
d
 ducated people ==> intelligent policy
e
 merica is losing to the competition
A
 ong-term consequences to sustainability
l