Stem Cell Engineering

Question 1

stem cell research aims to:

Answer 1

1. create tissues/cells for transplantation: bone marrow for leukemia and chemotherapy; nerve cells for PD and AD; heart muscles cells for heart disease; and pancreatic islet cells for diabetes
2. study cell differentiation (understand prevention and treatment of birth defects)
3. identify drug targets and test potential therapeutics
4. toxicity testing

Question 2

totipotency

Answer 2

ability of a cell to give rise to all cells of an organism, including embryonic and extra-embryonic tissues

e.g. zygote

Question 3

pluripotency

Answer 3

ability of a cell to give rise to all cells of the embryo and subsequently adult tissues

e.g. embryonic stem cells

Question 4

multipotency

Answer 4

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

e.g. adult stem cells

Question 5

embryonic stem (ES) cells

Answer 5

develop into different cell types with characteristics appropriate for that site (even germ cells)

capable of proliferating indefinitely in culture with unrestricted developmental potential

unable to generate a full organism

Question 6

how to get ES cells

Answer 6

inner cell mass at blastocyst stage

can extract ES cells and put back into blastocyst stage of animal and will integrate well with the embryo

Question 7

ES cells –> adipocyte requires

Answer 7

1. retinoic acid

2. insulin and thyroid hormone

Question 8

ES cells –> neuron requries

Answer 8

retinoic acid

Question 9

ES cells –> macrophage requires

Answer 9

1. macrophage colony-stimulating factor

2. interleukin-3 and 1

Question 10

ES cells –> smooth muscle cell requires

Answer 10

dibutyryl cAMP and retinoic acid

Question 11

ES cells –> astrocytes and oligodendrocytes requries

Answer 11

1. fibroblast growth factor
2. fibroblast growth factor 2; epidermal growth factor
3. fibroblast growth factor 2; derived growth factor

Question 12

ES cells have to be injected during blastocyte stage, if injected at another time

Answer 12

teratomas (tumors) form due to lack of cues and signals for proper differentiation

Question 13

high throughput screening

Answer 13

using stem cells to test large amounts of chemical compounds that show promise

Question 14

somatic cell nuclear transfer (SCeNT)

Answer 14

-combines cloning methods with embryonic stem cell technology to produce cells which are custom-made for patient

nucleus taken from somatic cell of patient and injected into oocyte of a donor replacing the oocyte nucleus –> blastocyst generated from this hybrid oocyte and ES cells isolated

Question 15

what condition is being treated with SCeNT

Answer 15

type I diabetes

Question 16

what cells can be injected with specific gene regulatory proteins so they form ES-like cells

Answer 16

fibroblasts

Question 17

Induced Pluripotent Stem Cells (iPSC)

Answer 17

somatic cells (fibroblasts) being reprogrammed to form ES-like cells by exposure to transcription factors (Oct4, Sox2, Kif4, Myc, and Nanog)

Question 18

What do Oct4, Sox2, Kif4, Myc, and Nanog genes do

Answer 18

• up regulate embryonic stem cell genes
• up regulate cell proliferation
• loosen chromatin structure
• down regulate differentiation genes

Question 19

main goals of Induced Pluripotent Stem cells (iPSC)

Answer 19

1. study treatment of drugs on tissues

2. transplantation of genetically matched healthy cells

Question 20

challenges for regenerative medicine and transplantation therapy

Answer 20

• production of cell types in pure form
• production of sufficient numbers
• delivery method
• proper integration into tissue/organ
• stability of cells in culture
• tissue/immune rejection**
• genetic and epigenetic changes**

Question 21

for repair of skin, artificial matrix graft is composed of

Answer 21

matrix of collagen and glycosaminoglycan with thin membrane of silicone rubber on outside

Question 22

how does cadaver or artificial graft result in healing

Answer 22

fibroblasts and blood capillaries from patient’s tissue migrate towards the artificial skin and reform connective tissue underneath graft while waiting for cultured epidermal cells to be ready