Introduction to stem cells

Question 1

Who proposed the ‘origin of the stem cell’?

Answer 1

Ernst Haeckel (1834-1919)

Question 2

What are the 2 senses of the origin of the stem cell?

Answer 2

1) The unicellular origin of the multicellular life

2) The fertillized ooctye as the origin of all cells

Question 3

Who proposed the germ plasm continuity?

Answer 3

August Weismann (1892)

Question 4

What is a sacrococcygeal teratoma and why are they important?

Answer 4

• Mixed array of embryonic tisssues
• Single cells can lead to new tumors (cancer stem cells)
• Look like ‘jumbled up embryos’

Are there cells in tumors that can rebuild embryos?

Question 5

What are EC cells?

Answer 5

• Embryonal carcinoma cells
• Stem cells of teratocarcinoma and the malignant counterparts of ES cells derived from the inner cell mass of blastocyst-stage embryos
  (In human or mouse)

Question 6

What are ES cells?

Answer 6

• Embryonic stem cells
• Derived from the
  undifferentiated inner mass cells of a human embryo
• Pluripotent

Question 7

What does pluripotent mean?

Answer 7

• Are able to differentiate into all derivatives of the three primary germ layers
• Make any cell

Question 8

What are PSCs?

Answer 8

• Pancreatic stellate cell.

Question 9

What is the malignant form of teratoma?

Answer 9

• Teratocarcinoma

- Stem cells

Question 10

What 3 things are stem cells capable of?

Answer 10

1) Self renewal (can make a copy of itself)
2) Make a range of cell types (potency)
3) Can convert into different cell types (differentiation)

Question 11

What do the features of stem cells allow them to do?

Answer 11

1) Build embryos and tissues (development)

2) Repair tissues (regeneration)

Question 12

Where do stem cells come from pre implantation?

Answer 12

Blastocyst

Question 13

Where do stem cells come from post implantation?

Answer 13

Epiblast
Feotal
Adult

Question 14

Where are pluripotent stem cells derived from?

Answer 14

ESC
- Blastocyst and epiblast (early mammalian embryo)

iPSC
- Or reprogrammed using transcription factors

Question 15

What are tissue-specific stem cells and their features?

Answer 15

ADULT STEM CELLS

• Can build are repair tissue
• Are multipotent
• Difficult to isolate and maintain in vitro

Question 16

Apart from the adult, where can tissue-specific stem cells be derived from?

Answer 16

Foetal tissue

Question 17

What are pluriopotent stem cells capable of?

Answer 17

• Growing indefinitely in vitro

- Making all the cells of the body (but NOT extraembryonic)

Question 18

What are the differences between pluripotent stem cells and tissue-specific stem cells in terms of proliferation and availibilty?

Answer 18

• Pluripotent stem cells = HIGH

- Tissue-specific stem cells = LOW

Question 19

What are the 4 uses of stem cells?

Answer 19

1) Basic research
- To understand the mechanisms of stem cells

2) Drug discovery
- Testing drugs using high throughput techniques (eg. with human ESC)

3) Cancer
- Investigate genetic stability and effects of chromosomal abnormalities on stem cells

4) Regenerative medicine
- Therapies for Parkinsons, diabetes, heart disease, liver faliure

Question 20

What are examples of degenerative diseases?

Answer 20

• Diabetes
• Alzhemier’s
• Parkinson’s
• Heart disease
• Liver faliure

Question 21

What are the steps to develop regenerative medicine and how many years does this take?

Answer 21

1) Basic research
2) Proof of concept (animal studies in vivo)
3) Develop robust methods
4) Ensure all procedures are safe (Good manufacturing procedures)

5) Phase I clinical trial
(safety)

6) Phase II
(efficacy)

7) Phase III
(prolonged trial)

• Takes 15-20 years!

Question 22

What is efficacy?

Answer 22

The ability to produce a desired/ intended result

Question 23

What are the risks or regenerative medicine?

Answer 23

• Lack of efficacy
• Side effects
• Cancer
• Immuno-rejection