Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MCDB 436: Immunology > Lecture 11: Intro to T cells; MHC structure, function and genetics in T cell recognition of antigen > Flashcards

Lecture 11: Intro to T cells; MHC structure, function and genetics in T cell recognition of antigen Flashcards

1
Q

Where are T-cells born?

A

Bone marrow

T-cells originate from hematopoietic stem cells in the bone marrow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where do T-cell precursors travel to mature?

A

Thymus

The thymus is critical for the development of T-cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the secondary lymphoid tissues where mature T cells travel?

A

Lymph nodes, spleen, GALT

Secondary lymphoid tissues are essential for immune response activation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of white blood cell are T-cells?

A

T lymphocytes

T-cells are a crucial component of the adaptive immune system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the two main types of mature T-cells?

A

CD4+ (helper T cells) and CD8+ (cytotoxic T cells)

These T-cells have distinct roles in immune response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the primary function of CD4 helper T cells?

A

Help B cells become plasma cells

CD4 cells assist in B-cell development and antibody production.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do CD8 cytotoxic T cells do?

A

Directly kill infected or cancerous cells

CD8 T-cells recognize and eliminate cells presenting non-self antigens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

True or False: T-cells can develop into multiple types with unique functions.

A

True

T-cells can differentiate into various subtypes based on signals received.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Fill in the blank: T-cells travel via the _______.

A

Bloodstream

T-cells circulate through the body in the blood to reach lymphoid tissues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of immune response do regulatory T cells provide?

A

Immune inhibition

Regulatory T cells help maintain immune tolerance and prevent overactive responses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the role of Th1 cells?

A

Help macrophages become more phagocytic

Th1 cells enhance the ability of macrophages to engulf pathogens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the function of lymph nodes?

A

Filters for lymph

Lymph nodes trap pathogens and activate T and B cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the function of the spleen?

A

Filter for blood

The spleen removes old or damaged blood cells and pathogens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does GALT stand for?

A

Gut-associated lymphoid tissue

GALT plays a vital role in immune function in the gastrointestinal tract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the types of CD4 helper T cells?

A

Th1, Th2, Th17, Treg, and Tfh

Each subtype has distinct roles in regulating immune responses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do BCRs recognize?

A

BCRs recognize any solvable protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do TCRs recognize?

A

TCRs can only recognize peptide portions of antigens presented by MHC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does MHC stand for?

A

MHC stands for Major Histocompatibility Complex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are T-cell receptors (TCRs) made up of?

A

TCRs are made up of two polypeptide chains that compose one antigen binding region.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What percentage of TCRs are composed of alpha and beta chains?

A

Approximately 95% of TCRs are composed of an alpha and a beta chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What percentage of TCRs are made up of gamma and delta chains?

A

The remaining 5% of TCRs are made up of gamma and delta chains.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where are gamma delta cells usually distributed?

A

cells are usually distributed in peripheral tissue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the function gamma delta T cells?

A

have a similar function to NK cells and play a role in innate immunity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is sometimes needed for a functional T cell?

A

Sometimes a CD3 co-molecule is needed to help transduce a signal to activate the T cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do T cells secrete?

A

T cells secrete cytokines and toxic proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is similar to the FAB fragment on antibodies?

A

The variable region (V) of TCRs is similar to the FAB fragment on antibodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the constant region (C) of TCRs similar to?

A

The constant region (C) of TCRs is similar to an Ig-like domain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the size of the alpha chain of TCRs?

A

The alpha chain is approximately 40-50 kDa.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the size of the beta chain of TCRs?

A

The beta chain is approximately 35-46 kDa.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What region of TCRs is exposed for specificity?

A

TCRs have a CDR exposed region for specificity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What do BCRs recognize?

A

can recognize antigens via either an energy segment or a 3D structure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How do T-cell receptors (TCRs) recognize proteins?

A

TCRs do not recognize soluble proteins; they recognize a complex made by peptide and MHC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the primary function of the T-cell receptor?

A

The primary function of the T-cell receptor is to recognize and bind to specific antigens presented by MHC molecules.

34
Q

What is involved in antigen processing?

A

Antigen processing involves the breakdown of proteins and the presentation of peptides by MHC molecules.

35
Q

What is recognized by the T-cell receptor?

A

The T-cell receptor recognizes the antigen-MHC complex on the cell surface.

36
Q

What is the ligand for a TCR?

A

The ligand for a TCR is the combination of peptide and MHC molecule at the cell surface.

37
Q

How is a mature peptide processed to be put in an MHC molecule?

A

Cut peptides so that multiple inside portions can meet multiple MHCs

38
Q

What do individual TCRs recognize?

A

Individual TCRs recognize only individual unique MHC-presented peptides.

39
Q

What is T-cell recognition of antigens restricted by?

A

T-cell recognition of antigens is MHC-restricted.

40
Q

Which T cells can recognize antigens?

A

Both CD4+ and CD8+ T cells can recognize antigens.

41
Q

When can T cells recognize antigens?

A

T cells can recognize antigens only when presented in the groove of an MHC molecule.

42
Q

What is MHC restriction?

A

MHC restriction is the dependence of T-cell receptors on self-MHC.

43
Q

Where does MHC restriction occur?

A

MHC restriction occurs as T cells are developing in the thymus.

44
Q

What is the survival dependence of T cells in the thymus?

A

The survival of T cells is dependent on engagement with self-MHC molecules present in the thymus.

45
Q

What happens before T cells mature?

A

Before T cells mature, a sophisticated screening process occurs.

46
Q

What can T cells weakly bind to during maturation?

A

Only T cells can weakly bind with their self-MHC and self-peptide.

47
Q

What happens if T cells don’t recognize self-peptide-MHC?

A

If T cells don’t recognize self-peptide-MHC, they won’t survive or leave the thymus.

48
Q

What do T cells show after leaving the thymus?

A

After leaving the thymus, T cells show weak binding to self-MHC with foreign peptides.

49
Q

What is a major issue for tissue graft rejection?

A

Host rejects MHC molecules.

50
Q

What is the MHC gene in mice called?

A

H2 - a major immune response gene.

51
Q

Who originally identified MHC in mice?

A

R.A. Gorer and G.D. Snell in the 1930s.

52
Q

What was the basis for defining MHC?

A

Tissue graft rejection.

53
Q

Who was awarded the Nobel Prize in 1980 for MHC discoveries?

A

George D. Snell.

54
Q

Who discovered the first compatibility antigen in humans?

A

Jean Dausset.

55
Q

What did Barui Benacerraf find about immune reactions?

A

They are controlled by the MHC genes (immune response genes).

56
Q

What did Rolf Zinkernagel and Peter Doherty reveal about T cells?

A

It is the complex of MHC molecule plus antigen that is recognized by T cells (MHC restriction of T cell responses).

57
Q

Who won the Nobel Prize in Physiology or Medicine in 1996?

A

Rolf Zinkernagel and Peter Doherty.

58
Q

What was the 1980 Nobel Prize awarded for?

A

“For their discoveries concerning genetically determined structures on the cell surface that regulate immunological reactions.”

59
Q

What are inbred strains of mice?

A

Genetically identical at all loci

60
Q

What discovery was made from experiments mapping the genetics of transplantation?

A

The discovery of the MHC

61
Q

What are the genotypes of the parental strains?

A

b/b and k/k

62
Q

What is the genotype of the F1 progeny?

A

Heterozygous at all loci (H-2b/k)

63
Q

What is required for skin transplants?

A

MHC identity

64
Q

What is the recipient type for a skin graft from F1 progeny?

A

Parental recipient

65
Q

What happens to tissue if MHC identity is not matched?

A

Tissue will be rejected

66
Q

How many MHCs does each APC have on the surface of the cell?

A

100,000 MHCs

67
Q

What does MHC stand for?

A

Major Histocompatibility Complex

68
Q

What is the significance of the experiments mapping the genetics of transplantation?

A

Led to the discovery of the MHC

69
Q

What are MHC molecules?

A

MHC molecules are a set of cell surface proteins.

70
Q

What are the two broad kinds of microorganisms that infect human tissues?

A

1) Extracellular, e.g. bacteria which live and replicate in the space between cells.
2) Intracellular, e.g. virus which live and replicate inside human cells.

71
Q

What is MHC class I associated with?

A

MHC class I presents endogenous proteins, such as viral or tumor proteins.

72
Q

What is MHC class II associated with?

A

MHC class II presents exogenous proteins.

73
Q

How do MHC class I and class II differ?

A

The two types have different pathways for presenting antigens.

74
Q

What forms the peptide binding groove in MHC class I?

A

MHC class I has a peptide binding groove formed by alpha (α1-3) domains and a beta (β)2-microglobulin domain.

75
Q

What forms the peptide binding groove in MHC class II?

A

MHC class II has a peptide binding groove formed by two alpha (α) and two beta (β) domains.

76
Q

Which chains in MHC 1 molecule bind to the antigen?

A

Alpha 1 and 2

77
Q

Which chains in MHC 1 molecule bind to the antigen?

A

Alpha 1 and 2

78
Q

What part of the MHC 1 complex has a transmembrane domain?

A

Alpha 3 is the longer peptide that does this

79
Q

What chains on the MHC 2 complex binds to the antigen?

A

Alpha 1 and Beta 1

80
Q

What chain in the MHC 2 complex is transmembrane?

A

Alpha 2 and Beta 2 chains

81
Q

What chain in the MHC 2 complex is transmembrane?

A

Alpha 2 and Beta 2 chains

MCDB 436: Immunology (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions