Stem Cells

Question 1

A primitive cell that can either self-renew or give rise to more specialized cell types. It is highly regulated.

Answer 1

Stem cell

*progenitors are more differentiated (the original origin ones)

Question 2

What are characteristics of stem cells?

Answer 2

• not terminally differentiated
• can divide without limit (bc telomerase expression)
• undergo slow division
• divide into 1 stem cell and 1 differentiated cell

Question 3

Adult (mature) stem cells are known to be ________. They are committed to a specific lineage of the ectoderm, mesoderm, endoderm.

Answer 3

Tissue specific

Question 4

The proliferative potential of a stem cell is know as its _______

Answer 4

Potency

Question 5

Describe totipotency

Answer 5

• ability to give rise to all cells of an organism (embryonic and extra embryonic tissue)
• ZYGOTE of embryonic stem cell

Question 6

Describe pluripotent

Answer 6

• ability to give rise to all cells of the embryo (not extra embryonic cells)
• blastocyst of embryonic stem cells

Question 7

Describe multipotency

Answer 7

Ability to give rise to different cell types of a given lineage

*adult stem cells
(Adult/tissue/somatic stem cell)

Question 8

T/F
Pluripotent embryonic stem cells can be isolated and cultured and grown into different tissue types such as pancreatic islet cells, hematopoietic cells, cardiomyocytes, neurons, and hepatocytes

Answer 8

TRUE

Question 9

Ectoderm cell’s can become

Answer 9

Skin or neural cells

What makes you pretty: your outside (skin) and smarts (brain)

Question 10

Endoderm cells can become

Answer 10

Lung, thyroid, or pancreas

Question 11

Mesoderm cells can become

Answer 11

Cardiac cellls, hematopoietic, mesenchymal, or smooth muscle cells

Question 12

Cultured pluripotent stem cells make:

_____ for leukemia patients

_____ for Parkinson’s and AD

_______ for heart disease

________ for diabetes

Answer 12

Bone marrow

Nerve cell

Heart muscle

Pancreatic islet cells

Question 13

• short range signal determines the populations during development
• programmed to have a fixed number of divisions
• define the size of large final structures

Answer 13

Founder stem cells

*populations stay small but transit amplifying divisions let them generate and renew big adult structure

Question 14

How often to transit amplifying cells divide ?

Answer 14

Frequently

Question 15

Where do transit amplifying cells come from

Answer 15

Stem cell division; it is the cell that is carried on to be more differentiated

• it is committed
• have a finite number of divisions

Question 16

Stem cells have divisional asymmetry. What does this mean? How is it different than environmental asymmetry ?

Answer 16

• division of stem cells = 50% exact stem cells with original DNA and 50% transit amplifying cells with committed lineage
• environment asymmetry means that environmental factors influence cell differentiation

Question 17

What hypothesis summarizes that in asymmetrical stem cell division one daughter cell becomes a new stem cell with the exact DNA copy and the other daughter cell (transit amplifying cell) becomes differentiated and gets newly synthesizes strand of DNA

Answer 17

Immortal strand hypothesis

• way to prevent genetic error in stem cells
• result of semi-conservative DNA replication
• transit cells may get errors in newly synthesized DNA

Question 18

What markers in the cell’s DNA is involved in stem cell differentiation and cause the restriction of DNA expression therefore determining the type of cell a stem cell with turn into

Answer 18

Epigenetic markers

Silencing of some parts of genes by methylation

Question 19

In ES from the blastocyst, then can be placed back into ____ to integrate with the embryo, but if injected at a later stage or into an adult they will fail to differentiate properly and can become a tumor

Answer 19

Blastocyst

Question 20

Es cells can give rise to what type of tumor? And is the downfall of ES stem cell use

Answer 20

Tertomas (with teeth and hair)

Question 21

What are the transcription factors that are responsible for making ES pluripotent cells

Answer 21

Nanog, Oct4, Sox2, FoxD3

Question 22

What are growth factors found in pluripotent cells that make it differentiate ?

Answer 22

Cripto and GDF-4

*GCNF important for early stage pluripotent cell differentiation

Question 23

Adult stem cells respond to what

Answer 23

Respond to demands of growth and repair

*found in tissues

Question 24

T/F
Adult stem cells may show relaxation of restrictions in an altered environment that can possibly account for some plasticity

Answer 24

True

*seen in low frequency’s

Question 25

Adult stem cell therapies

Answer 25

- limited clinical use because cannot change lineage of cells - reduced teratoma risk - used in bone marrow transplants

Question 26

Similarities and differences of hematopoietic and stromal stem cells

Answer 26

Similarities 1. Both come from bone marrow Difference: 1. Differentiate into two different things

Question 27

What are hematopoietic stem cells differientiated into

Answer 27

Blood components - platelets - RBC - WBC

Question 28

What are stromal stem cells differentiated into

Answer 28

*mesenchymal stem cells Connective tissue and tissues - bone - cartilage - fat - heart - liver - muscle - nerve

Question 29

T/F Cord blood is a type of stem cell that has been known to treat over 70 disease with the possibility of 1000’s new therapies but has ethical boundaries

Answer 29

True

Question 30

What are two ways you can get pluripotent stem cells

Answer 30

1. Patient derived (iPS) 2. Non-patient derived (ES) * useful for cell reprogramin in regenerative medicine

Question 31

T/F | Adult stem cell therapy can be used in Neuro-regeneration

Answer 31

True

Question 32

What are some challenges of regenerative medicine

Answer 32

- production of substantial amounts of stem cells - what cell to transplant - delivery and proper integration - immune rejection - whee to get it from - stem cells may be immunogenic and promote immune responses

Question 33

What is SCNT? And Why does somatic cell nuclear transfer (SCNT) not have a risk of immune rejection?

Answer 33

Because patients are using their own stem cells *nucleus is taken from somatic cell of patient and injected into the oocyte of a donor replacing the oocyte nucleus which makes a blastocyst and then ES cells can be isolated

Question 34

What are the 4 gene regulatory proteins of ES cells

Answer 34

OCT3, SOX2, Myc, KLf4

Question 35

Adult stem cells can become ES-like by injecting them into what?

Answer 35

Fibroblast Called Induced pluripotent stem cells (iPS cells) - uses recombinant DNA, and TFs (Oct4, Sox2, Nanog) to make pluripotent * HIGH TERATOMA POTENTIAL

Question 36

What is combined in SCNT in the beginning step

Answer 36

Denucleated egg cell with somatic cell from patient

Question 37

Where do you stop the SCNT process to stop both therapeutic application and cloning ability? And where do you stop the SCNT cycle to allow therapeutic research and stop cloning ability?

Answer 37

1. At fusion Site 2. Prohibiting implantation of blastocyst, but allowing culturing of pluripotent cells * Dolly was a clone made by this process

Question 38

Difference between “normal” formation of ES cells and “SCNT” formation of ES cells

Answer 38

“Normall” - ES cell from blastocyst SCNT- ES cell from SCNT derived blastocyst

Question 39

Challenges of SCNT treatment

Answer 39

* can be used in T1DM 1. Inefficient (may need hundreds of oocytes) 2. Technically demanding (needs to be available in many/ all hospitals)

Question 40

What are sources of oocytes?

Answer 40

Self, mother, relative, egg bank