Stem Cells

Question 1

Self renewal

Answer 1

ability to copy itself

Question 2

Potency

Answer 2

ability to change into other types of cells

Question 3

normal self-renewal

Answer 3

cells can divide a limited number of times

Question 4

immorality

Answer 4

the ability to self-renew indefinitely

Question 5

totipotent

Answer 5

can become all cell types including extraembryonic membranes

Question 6

pluripotent

Answer 6

can become all cells in the adult body

Question 7

multipotent

Answer 7

can become multiple cell types. Usually from only one germ layer

Question 8

Differentiation

Answer 8

a change from one cell type to another.

Question 9

Potency of children

Answer 9

generally decreases as cells differentiate. More developed organisms generally have more differentiated cells.

Question 10

Stem cell applications

Answer 10

study of developmental processes, tissue engineering

Question 11

study of developmental processes

Answer 11

zygote is first stem cell. Reveals how cells in body develop

Question 12

Tissue engineering

Answer 12

formation of engineered tissues. Stem cells can be used to make new tissues. Tissues can be used to replace organs

Question 13

Embryonic Stem Cells (ESC)

Answer 13

cells are removed from inner cell mass. Kills the blastocyst. Often “extra” embryos from IVF are used. Immortal, pluripotent

Question 14

Immortality + pluripotency

Answer 14

provides an unlimited cell source, potential therapies for unlimited patients. Provided any cell potential in the body, potential therapies for any part in the body.

Question 15

Fetal Stem Cells

Answer 15

Sometimes improperly refers to fetal cells that are not stem cells.

Question 16

Fetal Proper Stem Cells (FpSC)

Answer 16

tissue from fetus proper. Generally obtained after an abortion. References to fetal stem cells that are accurate usually refer to these. Not immortal, but high level of division. Multipotent.

Question 17

Extrafetal Stem Cells (eFSC)

Answer 17

extraembryonic membranes (umbilical cord, placenta, amniotic fluid, etc.) Often not distinguished from adult stems cells, usually acquired soon after birth, tissue is thrown away, abundant untapped cell source. High level of cell division, pluripotent.

Question 18

Adult Stem Cells

Answer 18

tissue and fluids from adults or earlier; generally obtained after birth. Not immortal, multipotent.

Question 19

Induced pluripotent stem cells (iPSC)

Answer 19

a cell from the body that has been “reprogrammed”. Immortal, pluripotent

Question 20

Advantages of iPSC

Answer 20

All adult cell types, early developmental models, wide support

Question 21

What definitely produces all adult cell types?

Answer 21

ESCs, iPSCs. Have been directly shown to contribute to all tissues of an organism, confirmed through tetraploid complementation assays

Question 22

What probably produces all adult cell types?

Answer 22

eFSCs. Can create cells of all three major tissue types. Possess pluripotency markers.

Question 23

What probably doesn’t produce all adult cell types?

Answer 23

ASCs, FpSCs. May be “pluripotent” as a population. It may be possible to get any cell type if the correct stem cell is used. Individual cells are multipotent. Not all cell types are obtained from a single source.

Question 24

CIRM

Answer 24

$3,000,000,000 (billion) California tax dollars. Designed to fund embryonic stem cell research.

Question 25

Early developmental models

Answer 25

some cells can be used to investigate how the body grows/develops before birth. Useful in developmental models: ESCs, FpSCs, eFSs, iPSCs. Can provide cells from relatively early developmental stages. Not useful in developmental models:ASCs.

Question 26

Wide Support

Answer 26

some people may reject treatments that they have ethical objections to. Are treatments that half of the population would be unconfortable using prudent? Wide support: eFSCs, ASCs, iPSCs. Challenged: ESCs, FpSCs

Question 27

Significant disadvantages

Answer 27

tumors, immune rejection, pluripotency

Question 28

tumors

Answer 28

some stem cells form tumors when implanted into the body. Pluripotency is linked to tumor formation.

Question 29

tumor formation

Answer 29

ESCs, PfSCs, iPSCs. FpSCs from tumors despite multipotency.

Question 30

no tumors

Answer 30

eFSCs, ASCs. eFSCs avoid tumor creation despite pluripotency.

Question 31

Immune Rejection

Answer 31

the body attacks non-native cells. Treatments that don't use the body's own cells require suppression of the immune system.

Question 32

Immune rejection

Answer 32

ESCs, FpSCs. Cells must come from a non-native source.

Question 33

No immune rejection

Answer 33

eFSCs, ASCs, iPSCs. Cells can be taken from patient that they are used to treat. eFSCs and ASCs may not be rejected even if used from a non-native source.

Question 34

cloning

Answer 34

direct reprogramming is superior to cloning for the purposes of creating patient matched cells. He is abandoning cloning and focusing on direct reprogramming.

Question 35

problems with pluripotency

Answer 35

makes it difficult to obtain the exact cell type needed. Not all cells in a population differentiate uniformly. Undifferentiated or improperly differentiated cells can create tissues other than the desired type.

Question 36

Geron

Answer 36

Funded first human embryonic stem cell isolation. Leader in the embryonic stem cell field.

Question 37

Treatments

Answer 37

what has already helped some patients

Question 38

Clinical trials

Answer 38

treatments being tested for safety/efficacy

Question 39

research papers

Answer 39

what has a chance of working in the future. What is being investigated for future applications.