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Flashcards in Stem Cells Deck (74)
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1
Q

What properties define stem cells?

A
  1. ) They are unspecialized

2. ) The can be induced to differentiate into specific cells

2
Q

Are unspecialized and can self renew

A

Stem Cells

3
Q

Can be induced to differentiate into cells with special functions

A

Stem cells

4
Q

Predominates under steady-state conditions and serves to maintain a balance between differentiated and undifferentiated cells

A

Asymmetric division

5
Q

Predominate when stem cells must expand in number

-Ex: during development or injury

A

Symmetric divisions

6
Q

Asymmetrical segregation of factors that promote “stemness” to one daughter cell and not the other

A

Asymmetric division

7
Q

What essentially happens during asymmetric division?

A

2 cells are formed, one cell differentiates and and the other remains undifferentiated

8
Q

What are the two ways to regulate stem cell self-renewal

A
  1. ) Cell intrinsic regulation

2. ) Cell extrinsic regulation

9
Q

What are three transcription factors of cell-intrinsic regulation of stem cell self-renewal?

A

Sox2, Oct4, and Nanog

10
Q

Negatively regulate expression of differentiation-promoting genes

A

Sox2, Oct4, and Nanog

11
Q

Suppresses transcription of differentiation-inducing genes such as GATA4 and GATA6

-intrinsic regulator

A

Ronin (DNA binding protein)

12
Q

In the cell extrinsic pathway, LIF and BMP work through STAT3 and SMAD-Id to block the

A

MAPK pathway

13
Q

Blocking differentiation in stem cells leads to

A

Self renewal

14
Q

Describes the microenvironment in which the stem cells reside in their undifferentiated state

A

Stem cell Niche

15
Q

Tissue injury results in a respecification of the

A

Niche environment

16
Q

Respecification of the niche environment can result in increased

A

Proliferation and differentiation

17
Q

Stem cell division with maintenance of the undifferentiated state

A

Stem cell self-renewal

18
Q

An example of a stem cell niche is the

A

Intestinal crypt

19
Q

Stem cells in the intestinal crypt can give rise to

A

TA cells and Paneth cells

20
Q

Remain close in proximity to stem cells

-1:1 ratio with intestinal stem cells and stem cells won’t divide without them

A

Paneth cells

21
Q

What are the three types of stem cells

A
  1. ) Adult stem cells
  2. ) Embryonic stem cells
  3. ) Cancer stem cells
22
Q

An undifferentiated cell found in a differentiated tissue that can self renew and differentiate into all of the specialized cell types of the tissue from which it originated

A

Adult stem cell

23
Q

A type of pluripotent stem cell artificially derived from a non-pluripotent cell, typically an adult somatic cell, by inducing forced expression of specific genes

A

Induced pluripotent stem cells (iPS cells)

24
Q

Undifferentiated cells derived from a 5-day preimplantation embryo

-can differentiate into a wide variety of specialized cell types

A

Embryonic stem cells

25
Q

Cells that drive tumorigenesis and also give rise to differentiated progeny

A

Cancer stem cells (CSC)

26
Q

A cell that through the process of differentiation has acquired a specialized structure and function

A

Differentiated cell

27
Q

A cancer in which the cells are mature and look like cells in the tissue from which it arose

A

Differentiated cancer cell

28
Q

A cell that has not yet acquired a special structure or function

A

Undifferentiated cell

29
Q

A cancer in which the cells are very immature and “primitive” and do not look like cells from which it arose

A

Undifferentiated Cancer cell

30
Q

A process by which a partially or terminally differentiated cell reverts to an earlier developmental stage

A

Dedifferentiation

31
Q

The potential to differentiate is termed

A

Potency

32
Q

Can give rise to embryonic and extraembryonic tissues

-Exist up until 8 cell embryo

A

Totipotent stem cells

33
Q

Descendants of totipotent stem cells that can differentiate into cells from any of the three germ layers

A

Pluripotent stem cells

34
Q

An example of pluripotent stem cells are

A

ICM cells

35
Q

Stem sells that can differentiate into a number of cells, but only those of a closely related family of cells

-ex: hematopoetic stem cell

A

Miltipotent stem cells

36
Q

Stem cells that can differentiate into only a few cells, such as lymphoid or myeloid stem cells

A

Oligopotent stem cells

37
Q

When stem cells can produce only one cell type, their own, they are termed

-ex: muscle stem cells

A

Unipotent stem

38
Q

Unipotent stem cells are distinguished from non-stem cells because they have the property of

A

Self-renewal

39
Q

Their primary role is to maintain and repair the tissue in which they are found

A

Adult stem cells

40
Q

In bone marrow, two populations of adult stem cells have been identified. What are they?

A
  1. ) Hematopoetic stem cells

2. ) Stromal stem cells

41
Q

Forms all of the types of blood cells in the body

A

Hematopoetic stem cells

42
Q

Form bone, cartilage, fat, and connective tissue

A

Stromal stem cells

43
Q

Obtained from the inner cell mass of 4-5 day old blastocysts

A

Embryonic stem cells

44
Q

Can be cultured in vitro so that they are either prevented from differentiating or they are forced to differentiate

A

Embryonic Stem Cells

45
Q

In order to culture ES cells, ICM cells are plated onto a layer of

-provide source of growth and attachment

A

Mouse fibroblast feeder cells

46
Q

To culture ES stem cells in vitro and prevent them from differentiating, ICM cells are plated with factors that inhibit differentiation such as

A

Leukemia inhibitory factor (LIF)

47
Q

LIF binds to a heterodimer composed of LIF receptor and gp130, which activates

A

JAK/Stat3 signalling

48
Q

The activation of JAK/Stat3 signaling effectively blockes the

A

MAPK pathway (and thus differentiation)

49
Q

Typically, hematopoetic stem cells (HSCs) from long bones, hips, and spine are isolated using a method called

A

Multi-parameter flow cytometry

50
Q

We can identify stem cells using cell surface markers directed against specific

A

Membrane receptors

51
Q

The most common method of isolating stem cells is

A

Fluorescence-activated cell sorting (FACS)

52
Q

How are adult and embryonic stem cells stimulated to differentiate in vitro?

A
  1. ) Change chemical composition of medium
  2. ) Alter surface of culture dish
  3. ) Introduction of certain genes
53
Q

Gene expression must be maintained for a differentiated cell to remain committed to a specific

A

Phenotype

54
Q

To maintain gene expression, the transcription factor whose gene is activated can bind the

A

Enhancer of its own gene

55
Q

To maintain gene expression, we synthesize proteins that act on chromatin to keep the gene

A

Accessible

56
Q

If differentiation is dependent on a particular signaling molecule, the cell can make both the molecule and its receptor to maintain

A

Gene expression

57
Q

Cells can interact with one another to stimulate eachother to remain

A

Differentiated

58
Q

What are the five ways of obtaining human pluripotent stem cells?

A
  1. ) from Morula (before 16 cells)
  2. ) from ICM of blastocyst
  3. ) from primordial germ cells of a fetus
  4. ) from adult
  5. ) through somatic nuclear transfer
59
Q

There are 24 candidate genes for pluripotency factors that can be used to make iPS cells, what are 4?

A
  1. ) Oct4
  2. ) Sox2
  3. ) Klf4
  4. ) cMyc
60
Q

One of the challenges to reprogramming is that we have to perform genomic insertion and inserted genes can insert

A

Mutations

61
Q

Creates the potential for tumors because it is an oncogene

A

cMyc

62
Q

Formed in 2012 to build a collection of iPS cell lines for drug screening for a variety of disease

A

StemBANCC

63
Q

A “human liver” was synthesized using which stem cells?

A

Hepatocytes, endothelial stem cells, and mesenchymal stem cells

64
Q

In medical research, iPS cells have been used for

A

Disease modeling and drug development, organ synthesis, and tissue repair

65
Q

Tumors arise from cells termed cancer stem cells that have properties of normal stem cells, particularly

A

Self-renewal and Multipotency

66
Q

Unregulated cell growth is due to a disruption in the regulatory mechanism in

A

Stem cell renewal

67
Q

A stem cell disorder, and not a simple mechanism whereby cell proliferation is disrupted

A

Cancer

68
Q

One problem with cancer treatment is that stem cells divide slowly, giving themselves plenty of time to repair any damage caused by

A

Radio- or chemotherapy

69
Q

Stem cells retain the essential property of self-protection through the activity of

A

Multiple drug resistance transporters

70
Q

Thus, a mutation that allows for unbridled cell growth will render chemotherapy

A

Ineffective

71
Q

Conventional chemotherapies kill the bulk of the tumor but do not eliminate the

A

Cancer stem cells giving rise to it

72
Q

Tend to be chemoresistant

A

Stem cells

73
Q

The most common primary brain tumor with a median survival of about 1 year

A

Glioblastoma

74
Q

This poor prognosis is due to therapeutic resistance to

A

Temozolomide

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