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Name _________________________________ Period _____
Biotechnology
Introducing Stem Cells
Date ________
Manuel
Stem cell biology basics
In vitro fertilization – IVF
·Designed to _______________________________________ by removing
__________________________ from patients or donors.
·Fertilization takes place __________________________ and implanting some of the zygotes into a
receptive uterus
The world's first IVF baby Louise Brown (2nd right) with her son Cameron, her mother Lesley and IVF
pioneer Professor Robert Edwards. The procedure was done in _________________________________.
·IVF is now a very __________________________ practice although not ___________________
__________________
Commercially it is used to _________________________________.
-
_________________________________________________________________
·
Transporting ______________________________ is _______________________
_________________________________ than transporting live cattle
·For successful IVF, it is necessary to ____________________________________________________
(typically ______________) per session.
·Iimplantation is done usually __________________________ at a time
·The remaining eggs are ____________________________________________________ after a few cell
divisions
·While _______________________________________is an acceptable practice, the effects on the embryo
are still unknown.
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·The majority of frozen zygotes that are then implanted into healthy women develop into _____________
__________________________, however, __________________________ of zygotes do not survive the
freezing process.
- Parents can choose to have their eggs _______________________________________,
__________________________, or ____________________________________________________ like
human embryonic stem cell lines.
Of the estimated __________________________ frozen embryos in the U.S. less than _____________
have been donated to scientific research.
- A life story…
_____________________________________________________ starts with just _______________–
_____________________________________________.
This cell divides to produce 2 ‘_____________________________________________’. These daughters
_______________, and their daughters _______________ again, and so on.
There are a great many steps needed to form an ______________________________, or even a baby.
Along the way, lots of different types of cells must be made.
What is a Stem Cell?
There are a great many steps needed to form an adult
body, or even a baby. Along the way, lots of different
types of cells must be made.
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‘______________________________’ or ‘______________________________’ cells play particular roles
in the body, e.g. _______________ cells, _______________ cells, _______________ cells. Specialized cells
______________________________ divide to make copies of themselves. This makes
______________________________ very important. The body needs stem cells to _______________
specialized cells that die, are damaged or get used up.
1) ______________________________ is needed because if the stem cells didn’t copy themselves, you
would quickly ______________________________. It is important for the body to maintain a pool of stem
cells to use throughout your life.
2) __________________________ is important because specialized cells are _________________,
______________________ or ____________ all the time during your life. Specialized cells
____________________________________ and ______________________________ of themselves, but
they need to be replaced for your body to carry on working.
For example, your body needs ______________________________ new _______________ cells
______________________________. Of course, ______________________________ is also important
for making all the different kinds of cell in the body during development of an ________________________
from a single fertilized egg.
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Types of stem cell - Embryonic stem cells
A _____________________________________ has the potential to become an ______________
____________________________.
Since a fertilized egg begins to ____________________________, this is not a very useful stem cell for
research.
Soon after ______________________________, the fertilized egg begins to
______________________________, or develop different qualities and separate into layers.
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Where we find them
____________________________________________________________ are taken from inside the
______________________________, a very early stage embryo. The blastocyst is a ball of about
_______________ cells and it is not yet implanted in the womb. It is made up of an outer layer of cells, a
fluid-filled space and a group of cells called the _____________________________________________. ES
cells are found in the inner cell mass.
What they can do
Embryonic stem cells are exciting because they can make all the different types of cell in the body – scientists
say these cells are ______________________________.
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Challenges
Scientists around the world are trying to understand ______________________________ embryonic stem
cells produce _______________, _______________, _______________ or any other particular kind of
_______________ cell. What controls the process so that the stem cells make the right amount of each cell
type, at the right time?
How are embryonic stem cells grown in the laboratory?
Growing cells in the laboratory is known as ________________________________. Human embryonic
stem cells (hESCs) are generated by transferring cells from an embryo into a plastic laboratory culture dish
that contains a ________________________________ known as ________________________________.
The cells divide and spread over the surface of the dish.
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The _______________________________ of the culture dish:

typically coated with a _____________________________________
o ________________________________________________ that have been treated so they
will not ______________________________. This coating layer of cells is called a
______________________________.
o mouse cells act as an _________________ for the cells and a
__________________________________________________.
______________________________________________________________are then coated with a
blanket of ________________________________________________for additional nutrients.
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Researchers have devised ways to grow embryonic stem cells without mouse feeder cells. This reduces the
risk of ________________________________________________________ in the mouse cells may be
transmitted to the _____________________________________________
Stem Cell Line
The process of generating an embryonic stem cell line is somewhat ______________________________,
often, the plated cells _____________________________________________.
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However, if the plated cells __________________, __________________ and
_______________________ enough to crowd the dish, they are removed gently and plated into several fresh
culture dishes.
Before _______________, only ______________________________had been established. After George
W. Bush's ban on federally funded hESCs, only these 22 lines were legally allowed to be used for research.
This is a problem because ESC lines can:

develop ______________________________ as they get ______________________________,

rendering the entire line useless

a new ESC line must be established.
Culturing embryonic stem cells has many difficulties.
______________________________- typically a tumor of ______________________________
______________________________or partly differentiated cell types
But teratomas have their uses.
______________________________ are used as an indication that the _______________ ___________
______________________________are capable of ______________________________into
_____________________________________________
Embryonic stem (ES) cells: Challenges
Learning to control these fascinating cells is a big challenge.
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If we could _______________ their differentiation we would have a powerful tool for developing
_____________________________________________.
For example:

growing new ______________________________ cells to ______________________________
into a patient with _______________.
•
_________________________________________________________________________
•
_________________________________________________________________________
Embryonic stem (ES) cells: Challenges - Ethics
•
hESCs come __________________________________________donated by the parents.
•
They are not harvested from __________________________________________.
•
Does this constitute an ethical dilemma?
•
Are embryos considered ____________________________ or a
________________________________________________________?
•
Should research continue with human embryonic stem cells?
Embryonic stem (ES) cells: Challenges - Funding
Federal v. Privately Funded SC Research
Private Pros
·Private companies tend to ________________________________________________
·________________________ between rival companies can drive
____________________________________and
________________________________________________
·Funds for research can be procured from ________________________________________________
(investors, research grants venture capitalists etc
Private Cons
·Faster results can mean ____________________________________results
·Competition means a ________________________________________________ which can often
____________ discoveries
·Profit-driven motives cold lead to less attention being paid to ____________________________________
Federal v. Privately Funded SC Research
Federal Pros
·Federal researchers tend to produce ____________________________________________________
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·Federal researchers tend to
_________________________________________________________________
_______________________________________
·Having a single source of funds (_______________________________________) can help researchers
focus on the __________________________ rather than the __________________________
Federal Cons
·Research tends to __________________________due to federal __________________________
·Researchers must deal with _______________________________________ using taxpayer money leading
to a ____________________________________________________ to reaserch due to a
_________________________________________________________________.
Types of stem cell 2 - Tissue stem cells
Tissue stem cells - Where we find them
We all have ______________________________ in our bodies ______________________________.
They are essential for keeping us ______________________________. They _______________ cells that
are _______________ or _______________. Scientists are still learning about all the different kinds of tissue
stem cells found in our bodies and how they work.
_____________________________________________ can often make several kinds of
_____________________ cell, but they are more ______________________________ than
______________________________ stem cells. Tissue stem cells can
___________________________________________________________________________
_____________________________________________________________________________________
_____. So, ______________________________ can only make the different kinds of cell found in the
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_______________. ______________________________ can only make different types of
_______________ cell. _______________ stem cells can only make _______________ cells. And so forth.
Types of stem cell 3 - Induced pluripotent (iPS) stem cells
What are iPS cells?
In _______________, scientists discovered that it is possible to make a new kind of stem cell in the
laboratory. They found that they could _____________________________________________ from a
_______________ into cells that behave just like _____________________________________________.
In _______________, researchers did this with _______________ cells too. The new stem cells that are
made in the lab are called ____________________________________________________________. Just
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like embryonic stem cells, they can make all the different types of cell in the body – so we say they are
______________________________.
Making ____________________________________________________________ cells is a bit like turning
back time. Scientists add ______________________________ to cells from the body to make them behave
like _____________________________________________. _______________ give cells
_______________ about how to _______________. So, this process is a bit like
_____________________________________________
____________________________________________________________ to make the computer do a
_______________. Scientists call the process they use to make iPS cells ‘__________________________
______________________________’.
Why are they exciting?
Researchers hope that one day they might be able to use iPS cells to help treat diseases like
_______________ _____________________________________________. They hope to:
1) _________________________________________________________________
2) _________________________________________________________________
3) _________________________________________________________________
_____________________________________________________________________________
___________________________________________________
________________________________________________________________
There is a long way to go before scientists can do this, but iPS cells are an exciting discovery.
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Stem cell biology in more detail
Tissue stem cell types and hierarchies
Tissue stem cells: Principles of renewing tissues
Stem cells give rise to ______________________________________________. These are not fully
___________________________________________ but have different properties from stem cells – they
are an ___________________________________________________________________.
Committed progenitors will _____________________________________ and will give rise to __________
_____________________________ and _____________________________cells via a series of steps.
This typical hierarchy is applicable to many types of tissue stem cell (some examples are given in the following
slides to illustrate this principle).
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Tissue stem cells: Haematopoietic stem cells (HSCs)
HSCs = ______________________________________
HSCs are _______________________________________________________. They give rise to
committed progenitors, which then give rise to __________________________________________ cell
types.
Tissue stem cells: Neural stem cells (NSCs)
NSCs are ___________________________ from specific areas of the ______________. They give rise to
committed progenitors, which then give rise to ______________________________________ cell types.
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Tissue stem cells: Gut stem cells (GSCs)
GSCs = ___________________________________________________________
GSCs are present in the ____________________________. They give rise to committed progenitors, which
then give rise to _______________________________________________ cell types.
Tissue stem cells: Mesenchymal stem cells (MSCs)
MSCs are _______________________ from the ___________________________________. They give
rise to committed progenitors, which then give rise to _____________________________________ cell
types (bone, cartilage, fat).
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What cell therapies are available right now?
Current SC Therapies:
The only _________________________________________ currently in use is in ________________
_________________________________________. Blood-forming stem cells in the bone marrow were the
________________________________________________________ and were the first to be used in the
clinic. This life-saving technique has helped thousands people worldwide who had been suffering from
________________________________________________________________________.
Potential SC Therapies:
Many ______________________________ for
embryonic stem cell-based therapies have begun in
recent months. Results from those won't be
available until the trials reveal that the therapies are
___________
____________________________________—
which could take
______________________________.
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In addition to their current use in ____________________ treatments, research suggests that bone marrow
transplants will be useful in treating _________________________________ diseases and in helping people
tolerate ____________________________________________.
Other therapies based on ______________
______________________ are currently in
___________________________. Until those
trials are complete we won't know which type of
stem cell is most effective in treating different
diseases.
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Clinical Trials
Clinical trials are conducted in a series of steps, called _________________ - each phase is designed to
answer a separate research question.
Phase I: ________________ group testing to determine a __________________________________, and
identify ___________________________________.
Phase II: __________________ group testing for ______________________ and to further evaluate its
_______________________.
Phase III: _________________ group testing to confirm its _______________________, monitor
_______________________, compare it to commonly used treatments, and collect information that will
allow the drug or treatment to be used safely.
Phase IV: Studies are done ______________________ the drug or treatment has been ________________
to gather information on the drug's effect in ________________________________________ and any side
effects associated with _________________________________________
Stem Cell glossary
1. Blastocyst—A preimplantation embryo of about 150 cells produced by cell division following fertilization.
The blastocyst is a sphere made up of an outer layer of cells (the trophoblast), a fluid-filled cavity (the
blastocoel), and a cluster of cells on the interior (the inner cell mass).
2. Cell-based therapies—Treatment in which stem cells are induced to differentiate into the specific cell type
required to repair damaged or destroyed cells or tissues.
3. Cell culture—Growth of cells in vitro in an artificial medium for research or medical treatment.
4. Cell division—Method by which a single cell divides to create two cells. There are two main types of cell
division depending on what happens to the chromosomes: mitosis and meiosis.
5. Clone— (v) To generate identical copies of a region of a DNA molecule or to generate genetically identical
copies of a cell, or organism; (n) The identical molecule, cell, or organism that results from the cloning
process.
6. Committed progenitors - These are not fully differentiated cells but have different properties from stem
cells – they are an intermediate cell type
7. Differentiation—The process whereby an unspecialized embryonic cell acquires the features of a
specialized cell such as a heart, liver, or muscle cell. Differentiation is controlled by the interaction of a cell's
genes with the physical and chemical conditions outside the cell, usually through signaling pathways
involving proteins embedded in the cell surface.
8. Directed differentiation—The manipulation of stem cell culture conditions to induce differentiation into a
particular cell type.
9. Disease modeling - Understand how diseases develop
10. Ectoderm—The outermost germ layer of cells derived from the inner cell mass of the blastocyst; gives rise
to the nervous system, sensory organs, skin, and related structures.
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11. Embryo—In humans, the developing organism from the time of fertilization until the end of the eighth
week of gestation, when it is called a fetus.
12. Embryonic stem cells—Primitive (undifferentiated) cells derived from a 5-day preimplantation embryo
that are capable of dividing without differentiating for a prolonged period in culture, and are known to
develop into cells and tissues of the three primary germ layers.
13. Embryonic stem cell line—Embryonic stem cells, which have been cultured under in vitro conditions that
allow proliferation without differentiation for months to years.
14. Endoderm—The innermost layer of the cells derived from the inner cell mass of the blastocyst; it gives rise
to lungs, other respiratory structures, and digestive organs, or generally "the gut."
15. Enucleated—having had its nucleus removed.
16. Fetus—In humans, the developing human from approximately eight weeks after conception until the time
of its birth.
17. Gamete—An egg (in the female) or sperm (in the male) cell. See also Somatic cell.
18. Genetic reprogramming - the process they use to make iPS cells
19. Hematopoietic stem cell—A stem cell that gives rise to all red and white blood cells and platelets.
20. Human embryonic stem cell (hESC)—A type of pluripotent stem cell derived from the inner cell mass
(ICM) of the blastocyst.
21. Induced pluripotent stem cells—Somatic (adult) cells reprogrammed to enter an embryonic stem cell–like
state by being forced to express factors important for maintaining the "stemness" of embryonic stem cells
(ESCs).
22. Inner cell mass (ICM)—The cluster of cells inside the blastocyst. These cells give rise to the embryo and
ultimately the fetus. The ICM cells are used to generate embryonic stem cells.
23. Mesoderm—Middle layer of a group of cells derived from the inner cell mass of the blastocyst; it gives rise
to bone, muscle, connective tissue, kidneys, and related structures.
24. Multipotent - Can make multiple types of specialized cells, but not all types. Tissue stem cells are
multipotent
25. Oligodendrocyte—A supporting cell that provides insulation to nerve cells by forming a myelin sheath (a
fatty layer) around axons.
26. Parthenogenesis—The artificial activation of an egg in the absence of a sperm; the egg begins to divide as
if it has been fertilized.
27. Pluripotent - Can make all types of specialized cells in the body; Embryonic stem cells are pluripotent
28. Potency - A measure of how many types of specialized cell a stem cell can make
29. Somatic cell—any body cell other than gametes (egg or sperm); sometimes referred to as "adult" cells. See
also Gamete.
30. Somatic (adult) stem cells—A relatively rare undifferentiated cell found in many organs and differentiated
tissues with a limited capacity for both self renewal (in the laboratory) and differentiation. Such cells vary in
their differentiation capacity, but it is usually limited to cell types in the organ of origin. This is an active area
of investigation.
31. Stem cells—Cells with the ability to divide for indefinite periods in culture and to give rise to specialized
cells.
32. Teratoma— A multi-layered benign tumor that grows from stem cells injected into mice with a
dysfunctional immune system. Scientists test whether they have established a human embryonic stem cell
(hESC) line by injecting putative stem cells into such mice and verifying that the resulting teratomas contain
cells derived from all three embryonic germ layers.
33. Totipotent—Having the ability to give rise to all the cell types of the body plus all of the cell types that
make up the extra embryonic tissues such as the placenta.
34. Transdifferentiation—The process by which stem cells from one tissue differentiate into cells of another
tissue.
35. Umbilical cord blood stem cells—stem cells collected from the umbilical cord at birth that can produce
all of the blood cells in the body (hematopoietic). Cord blood is currently used to treat patients who have
undergone chemotherapy to destroy their bone marrow due to cancer or other blood-related disorders.
36. Undifferentiated—A cell that has not yet developed into a specialized cell type.
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