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Flashcards in Ch 9 Deck (79)
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1
Q

what are randomly generated by gene rearrangement

A

epitope-specific TCRs and BCRs

2
Q

self-reactive lymphocytes undergo what

A

apoptosis

3
Q

what is included in the B cell lineage

A

B 1 and B 2 cells

4
Q

what is included in the T cell lineage

A

alpha-beta TCRs
gamma-delta TCRs
NKT cells

5
Q

what cells are transitional

A

gamma-delta TCRs and B 1 cells

6
Q

what cells are adaptive

A

alpha-beta TCRs and B2 cells

7
Q

precursors of the T cell lineage

A

prothymocytes

8
Q

migrate from bone marrow to the thymus

A

prothymocytes

9
Q

enter at cortical region and lacks TCRs, CD3, CD4, CD8 molecules

A

thymocytes

10
Q

how much percent of thymocytes become T cells

A

5%

11
Q

remainder of thymocytes leaves what

A

thymus before selection or die by apoptosis

12
Q

When cells arrive at the thymus, they can become what

A

NK cells, dendritic cells, B cells and even myeloid cells

13
Q

a receptor on cells commits them to the T lineage

A

notch

14
Q

can commit cells to T lineage even without the thymus being present

A

notch binding

15
Q

dense outer region

A

cortex

16
Q

looser inner region

A

medulla

17
Q

connective tissue capsule with

A

trabeculae

18
Q

arrive from the bone marrow as double negative cells that do not express CD4, CD8, CD3, or TCR

A

precursor cells

19
Q

proliferate and differentiate into double positive thymocytes that express both CD4 and CD8 in addition to CD3 and TCR

A

double negative cells

20
Q

die within 3-4 days unless they recognize pMHC I or pMHC II on cortical epithelial cells in the cortical region

A

double positive cells

this is also known as positive selection

21
Q

surviving positive selection express only CD4 or only CD8 in addition to CD3 or TCRs

A

thymocytes

22
Q

interact strongly with self peptides on MHC I or pMHC II of antigen presenting cells undergo apoptotic death

A

medullary thymocytes

this is also known as negative seletion

23
Q

cross the endothelium of a venule and exit they thymus as T cells

A

mature single positive thymocytes

24
Q

very early thymocyte development occurs in the bone marrow

A

alpha-beta T cell

25
Q

Different stages of alpha-beta T cell (five)

A

double negative
double positive
positive/negative selection to become a single positive
final screening to remove autoreactive cells
release into the peripheral bloodstream

26
Q

recombination of TCR gene segments occurs in the double negative stages, yielding what

A

either an alpha-beta or a gamma-delta T cell

27
Q

selection must bind to MHC

A

positive

28
Q

selection removal of cells that interact with antigen-presenting cells

A

negative

29
Q

if a cell passes both negative and positive selection is will what

A

leave the thymus and become T cells

30
Q

what percent of cells fail positive selection and fail to receive needed survival signals

A

95

31
Q

selects thymocytes bearing receptors capable of binding self-MHC molecules, resulting in MHC restriction

A

positive selection

32
Q

selects against thymocytes bearing high-affinity receptors for self-MHC/peptide complexes, resulting in self-tolerance

A

negative selection

33
Q

what cells make up 80% of thymic cells

A

double positive thymocytes

34
Q

migrate preferentially to respiratory organs, skin, peritoneal cavity

A

gamma-delta T cells

35
Q

leave the thymus shortly after receiving TCRs and CD3

A

gamma-delta T cells

36
Q

have limited variability, respond quickly, and no memory

A

gamma-delta T cells

37
Q

Very early thymocyte development occurs in the bone marrow

Cells migrate to the thymus for further development

A

Alpha beta T cell

38
Q

Recombination of TCR gene segments also occurs in the double negative stages yielding what

A

Alpha beta T cell

Gamma delta T cell

39
Q

What are the different stages that cells migrate for further development

A

Double negative
Double positive
Positive or negative selection become a single positive
Final screening to remove auto reactive cells
Release into the peripheral bloodstream

40
Q

Must bind to MHC

A

Positive selection

41
Q

Removal of cells that interact with antigen presenting cells and it is potentially auto reactive

A

Negative selection

42
Q

If this passes both negative and positive selection what happens

A

Becomes a T cell and leaves the thymus

43
Q

Double positive thymocyte a make up what percent of thymocyte cells

A

80

44
Q

Selects thymocyte said bearing receptors capable of binding self-MHC molecules, resulting in MHC restriction

A

Positive selection

45
Q

Selects against thymocyte a bearing high-affinity receptors for self-MHC/peptide complexes, resulting in self-tolerance

A

Negative selection

46
Q

What percent of cells fail positive selection and fail to receive needed survival signals

A

95

47
Q

What cortical thymocyte a express alpha beta TCR and only later express CD4 and CD8 to become what type of thymocyte

A

Double negative

Double positive

48
Q

What type of cells attempt to bind with pMHC I or pMHC II on cortical epithelial cells

A

Double positive

49
Q

Double positive thymocytes that bind pMHC II cease what

A

CD8 expression

50
Q

Double positive thymocytes that fail to bind to either pMHC I or pMHC II will do what

A

Die

51
Q

Double positive thymocytes that bind pMHC I cease to do what

A

CD4 expression

52
Q

What type of thymocytes migrate to the thymus medulla

A

Single positive

53
Q
Do not undergo same selection process
Leave thymus shortly after receiving TCRs and CD3
Limited variability
Respond quickly
No memory
A

Gamma delta T cell

54
Q

What type of T cell migrates preferentially to respiratory organs, skin, peritoneal cavity

A

Gamma delta T cell

55
Q
Express several markers and receptors
Undergo some development in thymus 
Express TCRs 
Limited in repertoire to lipids, glycolipids, and some specialized peptides
Either CD4 or CD4CD8
Recognize nonclassical MHC I molecules
A

NK T cell

56
Q

Cell death without triggering inflammation

Programmed cell death

A

Apoptosis

57
Q

Results from injury and it is the release of cell contents meaning inflammation

A

Necrosis

58
Q

The site of what generation changes during gestation

A

B cell

59
Q

Blood cell development changes locations until bone marrow is formed and can take over

A

B cell

60
Q

What doesn’t exist at fertilization

A

Bone marrow

61
Q

Contains connective tissue, blood vessels, fat, and cells and has vascular importance

A

Bone marrow

62
Q

Give rise to myeloid, granuloid, erythroid, and lymphoid cells

A

Hematopoietic stem cells

63
Q

Stem cells within this differentiate into many cell types
Stromal cells provide support and growth factors to developing cells
Structure is dynamic and complex

A

Bone marrow

64
Q
Conventional and widely distributed 
Require interaction with T cells for activation and proliferation
Continually replace from bone marrow 
Vast repertoire
Repeated antigen exposure meaning stronger, faster response
Often accompanied by class switching
Immunologic memory
More IgD expressed gotten IgM
A

B2 cells

65
Q

Arise from fetal liver
Importance in innate and autoimmunity
Limited repertoire
Often directed against conserved microbial antigens
Most natural antibodies
Predominantly in areas of microbial entry
Self renewing

A

B1 cells

66
Q

What is different in the fetal liver from that in the adult bone marrow

A

Hematopoietic

67
Q

What are the major sites of B1 cells vs the B2 cells

A

B1 peritoneal and pleural cavities

B2 secondary lymphoid organs

68
Q

How does b1 cells get new cells vs b2

A

B1 self renewing

B2 precursors in the bone marrow

69
Q

How diverse is b1 vs b2

A

B1 restricted diversity

B2 highly diverse

70
Q

Which B cell 1 or 2 has somatic hyper mutation

A

B2

71
Q

Which types of Ig is produced in b1 and b2

A

B1 IgM

B2 IgG

72
Q

Which B cell responds to carbohydrate antigens

A

B1

73
Q

Which B cell responds to protein antigens

A

B2

74
Q

Which B cell has memory

A

B2

75
Q

Hematopoiesis stages are defined by what three things

A

Cell-surface markers
Transcription factor expression
Ig gene rearrangements

76
Q

What does both b and T cell developmental pathways share

Four things

A

Rearrangement of gene segments
Screening processes to avoid self-reactivity
Production of small subsets with discrete functions
Production of larger general purpose subsets

77
Q

What screening processes are used in B cells and T cells

A

T cells positive and negative selection

B cells negative selection

78
Q

B cells require what to hell and secrete antibodies

A

T cells

79
Q

T cells require what for helper and killer subsets

A

Presentation and differentiate