Stem
Cells
http://www.dnalc.org/resources/animations/stemcells.html
Objectives

What are stem cells?

What are the different types and where do
they come from?

What are the potential new medical
treatments using stem cells?

What research is needed to make such
treatments a reality?
What are stem cells?



Remarkable potential to develop into
different cell types
As each new cell divides it has potential to
remain a stem cell or another specialized
cell like muscle, RBC or brain cell.
May serve as an internal repair system:
Divide without limit
Different from other cell types
1.
2.
They are unspecialized cells capable
of renewing themselves thru cell
division
They can be induced to become
tissue or organ-specific with special
fxns
Types of Stem Cells



Embryonic stem
cells
Somatic or
adult stem cells
2006, induced
pluripotent
stem cells
Embryonic stem cells



Pluripotent: capacity to become ANY
cell
Grow easy in culture
Large numbers are easily harvested
IPSCs



First human cells introduced in lab in
2007
Genetically reprogrammed to an
embryonic stem cell like state by
being forced to express genes
Demonstrate the ability to be
pluripotent
Adult Stem Cells

Found in brain, bone marrow, blood, skeletal
muscle, skin, heart, liver, ovaries and testis

Once removed from body, Capacity to divide is
limited

Trying to figure out how to regenerate in large
quantities to use

Rare in mature tissue

Not supported yet, but less likely to be rejected
Why do we have stem cells?


Blastocyst : inner cells give rise to
entire body
Bone marrow: generate
replacements for cells that are lost
thru injury, disease or normal wear
and tear.
What is the potential new medical
treatments using stem cells?

Offer potentials for treating diseases
like diabetes, heart disease,
Parkinson’s and Alzheimer's


Screen new drugs
Develop model systems to study
normal growth and id causes of birth
defects.
A new treatment strategy that specifically
targets cancer stem cells, when combined
with current treatments, may lead to a
more complete and durable regression of
malignant cancers.

Continues to advance knowledge
about how an organism develops
from a single cell and how healthy
cells replace damaged cells
What research is needed to make
such treatments a reality?





Number and type of adult stem cells
that exist. What tissues contain
How they evolve during development
How do stem cells remain in
undifferentiated state, but other cells
around them are differentiated?
Donor specificity
Factors that stimulate stem cells to
relocate to sites of injury?




If you had in vitro fertilization
perform and as a result have frozen
embryos remaining, what would you
do with them?
Why?
What do you need to know to help
you make an informed decision?
Support your argument with details
from the article, “Frozen Dreams”,
What you have learned in class and
outside research you have done on
stem cells.