Stem cells

Question 1

What are the characteristics of stem cells?

Answer 1

• Unspecialised
• capable of self-renewal
• can become specialised cell types

Question 2

How do we know we have stem cells in our body?

Answer 2

We have the capacity to renew our cells and repair our tissues.

Question 3

What does potency refer to?

Answer 3

Number of types of cells that can be produced

Question 4

Unipotent

Answer 4

• Gametes

* Capable of giving rise to only one type of cell

Question 5

Potency of somatic stem cells

Answer 5

Multipotent

Question 6

What are the cell culture conditions?

Answer 6

• Cells grow in nutrient rich solution (media)
• House in incubator at 37℃ with 2-20% oxygen
• cells grown, divide and can be induced to become specialised cells

Question 7

Why is the media red?

Answer 7

• the culture medium shows pH with colour

* pinkish colour because cells in the body like to be at pH 7

Question 8

What are the characteristics of an embryonic stem cell?

Answer 8

• unlimited numbers
• self-renew
• pluripotent

Question 9

MSC

Answer 9

Mesenchymal Stem cells
• Cells isolated from bone marrow
• shown to be capable of making bone, cartilage and fat cells.
• multipotent

Question 10

What are the Yamanaka factors?

Answer 10

The groups of genes that can be added to any type of cell in the body to produce iPS (induced pluripotent stem) which can differential into any type of cell (but not embryonic)

Question 11

Difference between somatic/MSC stem cells and ES/iPS cells

Answer 11

Potency
• Somatic/MSC - Multipotent
• ES/iPS - Pluripotent

Quantity and in-vitro expansion
• somatic: most tissues occur in low number and cannot be cultured for very long
• ES & iPS cells - Can be kept in culture long term and can be expanded into large numbers needed for stem cell therapy

Question 12

iPS cells

Answer 12

Induce Pluripotent stem cells
• derived from skin or blood cells that have been reprogrammed back into an embryonic-like state
• can differentiate into any type of human cell needed for therapy

Question 13

ES cells

Answer 13

Embryonic stem cells

• pluripotent stem cells derived from the inner cell mass of a blastocyst (4-5 days post fertilisation)

Question 14

What are the current conclusions about the specialisation of stem cells?

Answer 14

• somatic cells are not permanently specialised

* somatic cell nuclei can be induced to change specialisation

Question 15

2 types of spinal cord injury

Answer 15

Traumatic
• stem from a sudden traumatic blow to spine that fractures, crushes or compresses

Non-traumatic
• May be caused by arthritis, cancer, inflammation or infections

Question 16

Totipotent

Answer 16

Can give rise to any type of cell

e.g. zygote

Question 17

Pluripotent

Answer 17

Can give rise to several different types of cells

e.g. embryonic stem cells

Question 18

Multipotent

Answer 18

Can give rise to multiple types
• Most adult stem cells are multipotent
• hematopoietic stem cells from bone marrow

Question 19

Trophoblast

Answer 19

Cells forming the outer layer of a blastocyst, which provide nutrients to the embryo and develop into a large part of the placenta