Ch. 5 pt 2

Question 1

Intestinal stem cells differentiate as they move upwards away from the _______

Answer 1

crypt

Question 2

Intestinal cells undergo _______ at the tips of the villi

Answer 2

anoikis

Question 3

What are the 2 paracrine gradients for the intestinal epithelium stem cell niche?

Answer 3

1) Wnt2b
2) Bmp4

Question 4

_______ promotes proliferation by binding to the Frizzled 7 receptor

Answer 4

Wnt2b

Question 5

_______ promotes differentiation of ISC’s by binding to the bmpr1 receptor

Answer 5

Bmp4

Question 6

Where are hematopoietic cells located?

Answer 6

bone marrow
- 1.15 million cells a second

Question 7

Hematopoietic stem cell niche was first described by Russian _______

Answer 7

Alexander Maximov (stammzelle)

Question 8

HSC’s aren’t created in the bone marrow but find their way into the marrow during development through a process called “______”

Answer 8

homing

Question 9

Describe homing of Hematopoietic stem cells (4 terms)

Answer 9

• CXCL4 receptor binds to CXCL12
  chemokine produced by osteoblasts and
  stromal cells of the marrow
• E-selectins and VCAM are also involved

Question 10

What are the 2 regions of the hematopoietic stem cell niche?

Answer 10

1) endosteal niche
2) perivascular niche

Question 11

In the endosteal niche, division is focused on _______ organism survival of stem cell population and HSC’s interact directly with _______

Answer 11

long-term
osteoblasts

Question 12

In the perivascular niche, division is _______ for renewing progenitor populations for short periods of time and HSC’s are associated with _______

Answer 12

short-term
blood vessels

Question 13

_______ cells can give rise to multiple cell lineages and play an important role in tissue repair/regeneration

Answer 13

multipotent cells

Question 14

What are 2 examples of multipotent stem cells?

part 2

Answer 14

bone-marrow derived stem cells (BMDC)
mesenchymal stem cells (MSC)

Question 15

Mesenchymal stem cells are found in many adult tissues and resemble fibroblasts, but can be cultured to _______ and produce a variety of _______

Answer 15

self-renew
cells

Question 16

Mesenchymal cell differentiation can be driven by _______ and _______

Answer 16

paracrine factors
interactions with ECM

Question 17

The identification of _______ in many organs presents exciting hopes for new types of therapies to repair/regenerate diseased or damaged parts

Answer 17

adult stem cells
- in very small numbers with slow proliferation

Question 18

______ show that even in small numbers adult stem cells can be used to reproduce an entire functional organ/organ system

Answer 18

bone marrow transplants
- ex) single transplanted cell in mice to reproduce blood, immune system, mammary gland

Question 19

The _______ is probably the most widely studied cell type in the world and was taken from _______

Answer 19

HeLa cell line
human tumors
- henrietta lacks
- Died in 1951 (cancer)

Question 20

_______ pluripotent stem cells from ICM of early blastocysts

Answer 20

embryonic stem cells (ESC)

Question 21

_______ from primordial germ cells that have not yet differentiated into sperm or egg

Answer 21

Embryonic germ cells (EGC)

Question 22

______ ESC: most undifferentiated, greatest potential for pluripotency

Answer 22

naive

Question 23

_______ ESC: some maturation towards epiblast lineage, possible reduction in pluripotency.

Answer 23

primed

Question 24

Pluripotency of ESC is maintained in culture by core TF’s: (3)

Answer 24

1) Oct4
2) Nanog
3) SOX2

Question 25

What inhibitors are used to maintain ESC state? (2)

Answer 25

1) Leukemia inhibitory factors (LIF) 2) kinase inhibitors (2i) - MEKi - GSK3i

Question 26

in 2006 researchers in japan demonstrated that by inserting activated copies of 4 genes they could transform nearly any adult cell into an _______

Answer 26

Induced pluripotent stem cells (iPSC)

Question 27

What are the 4 Yamanaka factors?

Answer 27

1,2) Oct4/Sox2 - activates nanog and other TF 3) C-Myc - opens up chromatin 4) Klf4 - prevents cell death

Question 28

______ homeodomain transcription factor that helps establish ESC identity

Answer 28

Nanog

Question 29

Know there are medical uses for iPSC's

Answer 29

Sickle cell anemia transplant in mouse

Question 30

Researchers have been able to grow rudimentary organs from pluripotent stem cells called _______, which are generally small and can be maintained in culture for extended periods of time

Answer 30

organoids - will self organize due to cell adhesion

Question 31

cerebral organoids were made by placing brain tissue organoids into matrixgel and then moving neuroepithelial buds into a _______

Answer 31

spinning bioreactor -increased nutrient uptake and growth

Question 32

Stem cell research may be the beginning of a revolution that will be as important for medicine (and as transformative for society) as the research on infectious _______ was a century ago

Answer 32

microbes

Question 33

Stem cells certainly give credence to the view that, “_______ never stops”

Answer 33

development