Brainscape's Knowledge GenomeTM

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


See full index

Principles of Medicine (POM) > POM 08 - T cells and antibodies in infection > Flashcards

POM 08 - T cells and antibodies in infection Flashcards

1
Q

what are the 2 types of immunity

A

innate and adaptive

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

for the innate immune system what does it recognize, when is it recruited into the immune response, and how does it respond to repeated exposures

A

recognizes broad patterns

generally early defenses

no difference with repeated exposures

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

for the adaptive immune system what does it recognize, when is it recruited into the immune response, and how does it respond to repeated exposures

A

recognizes highly specific antigens

generally later defenses

results in immunological memory from repeated exposure

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

what are the 2 branches of the adaptive immune system

A

humoral immunity

cell mediated immunity

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

humoral immunity is a product of ____ and it involves ____

A

product of B cells

involves antibodies

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

cell mediated immunity is a product of ____ and what is its antibody ivolvement

A

product of T cells

does not involve antibodies

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

where does the humoral immunity operate and what does it operate against

A

operates against antigens/specific shapes

operates outside of cells

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

what kinds of pathogens does the humoral immune system act against and how

A

viruses and toxins - stops attachment and coats toxins with antibodies

extracellular bacteria - enhance opsonization and phagocytosis and activates complement

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

where does the cell mediated immunity operate and what does it operate against

A

operates against antigens inside cells

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

what kinds of ‘pathogens’ does the cell mediated immune system act against and how

A

virus infected cells

tumour cells

transplanted organs

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

why do we need more than antibodies

A

viruses grow inside of cells and are therefore inaccessible to antibodies

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

what are the 2 lineages of T lymphocytes

A

cytotoxic/killer T cell

helper T cell

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

what is the role of killer T cells

A

kill cells with foreign/altered intracellular protein antigens

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

what is the role of helper T cells

A

produce cytokine hormones to assist other responses

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

what is VDJ recombination

A

range of specifications generated by complex recombinations of different genes inside the T cells as they mature in thymus

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

what is CD8 important for

A

activation of cells

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

are all T cell receptor specificities the same - what is the clinical implication of this

A

no there are different specificities so different shapes of receptors possible

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

what does CD3 do

A

links to T cell receptor and carries signals to T cell that can activate T cell to do some killing if antigen binds to T cell

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

what are the molecules and receptors on killer T cells

A

CD8

T cell receptor

CD3

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

what are the molecules and receptors on helper T cells

A

CD4

T cell receptor

CD3

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

what antigens can be ‘seen’ by helper T cells

A

only see antigens on specialized cells that can present antigens eg macrophages. dendritic cells etc

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

what does class 1 HLA present and what does it present to

A

presents antigens from any cell in the body onto the surface of the cell

only presents to killer T cells

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

where are the antigens that class 1 HLA present

A

in the cell - endogenous

antigen is inside cytoplasm could be from virus/mutations

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

what does class 2 HLA present and where are they found

A

presents antigens (usually phagocyte)

only found on antigen presenting cells

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

where are the antigens that class 2 HLA present

A

exogenous antigen - eaten into the cell

macrophage have phagocytosed something that contains an antigen and then they present antigen they’ve eaten up on the surface

26
Q

what are HLA

A

mechanisms to present intracellular antigens on surface of any body cell and allows the cytotoxic killer T cells to see antigen and respond to it

27
Q

what does MHC stand for

A

major histocompatibility complex

28
Q

what does HLA stand for

A

human leukocyte antigen complex

29
Q

are MHC and HLA the same

A

yes

30
Q

what is the structure of the MHC/HLA

A

2 parts made up of different classes

class 2—class 3—class 1

31
Q

regarding the structure of the MHC/HLA class 2 section what are the 3 main genes

A

HLA-DP

HLA-DQ

HLA-DR

32
Q

regarding the structure of the MHC/HLA class 3 section what is it and where is it found

A

cluster of genes between class 1 and 2 all on chromosome 6

33
Q

regarding the structure of the MHC/HLA class 3 section what does this section do

A

encodes signaling molecules involved in immune response and complement

34
Q

regarding the structure of the MHC/HLA class 1 section what are the 3 main genes

A

HLA-C

HLA-B

HLA-A

35
Q

the HLA-A/B/C section of the HLA class 1 section is said to be polymorphic what does this mean

A

in human population for each A/B/C there is a large number of different gene variations with slightly different sequences and coding proteins with slightly different gene sequences

ends up with a combination of these in each person

36
Q

what is the structure of HLA class 2 on the cell surface

A

2 chains - one alpha one beta chain

37
Q

what is the structure of HLA class 1 on the cell surface

A

one chain plus one B2-microglobulin molecule

38
Q

where are class 1 HLAs found

A

on virtually all nucleated cells

39
Q

what do class 1 HLAs do

A

present peptides/antigen to killer/CD8 T cells

40
Q

what dominance do the class 1 HLA show

A

codominance

41
Q

where are class 2 HLAs found

A

found on specialised antigen presenting cells - usually phagocytes

42
Q

what do class 2 HLAs do

A

present peptides/antigens that have been eaten up to CD4 T cells

43
Q

describe how the class 1 HLA presents to CD8 cytotoxic T cells

give example for when a virus has infected the cell

A

class 1 displays a sample of peptides derived from inside the cell from what the cell is making and metabolising

eg if virus infected cell peptides from virus replication

44
Q

what happens after the antigen is presented by class 1 HLAs

A

in secondary lymphoid organs the CD8 T cells with the right T cell receptor to the antigen start to expand

they can get help from helper T cells and the CD8 cells proliferate and differentiate into cytotoxic T cells which kill virus-infected/cancer cells

45
Q

what is the role of memory cells

A

some cells become memory cells to rapidly mount a quicker immune response if the same virus comes back

46
Q

describe how the class 2 HLA presents to CD4 helper T cells

give example for when antigenic material like extracellular bacteria has been phagocytosed into the cell

A

phagocytosis of extracellular bacteria

lysosomes break down proteins into individual peptides

some of these peptides can be processed and linked onto the MHC class 2

peptide is presented to CD4 helper T cells

47
Q

what happens after the antigen is presented by class 2 HLAs

A

in secondary lymphoid organs the helper T cells with the right T cell receptor for the antigen sends helper signals to other APC and CD4

the original helper T cell also expands and secretes cytokines and chemokines to help drive the immune response against the antigen/pathogen

helper T cells fully activated and some become memory cells

48
Q

what is the structure of antibodies

A

a light chain and heavy chain joined in the middle by disulfide bonds

49
Q

what is the Fc region on antibodies in terms of what it does

A

always constant

if antibody binds to something for it to then activate next step of immune response the constant region must be the same so the mechanisms and immune system can recognise it

50
Q

where is the Fc region found on antibodies

A

on the heavy chain end

51
Q

where are the antigen binding sites found on antibodies

A

on the ends of the 2 light chains

52
Q

what is the antigenic epitope

A

part of antigen that is recognized by an antibody or T cell

53
Q

describe the possible affinities of the T cell receptors and antibodies

what is the significance of this

A

many T and B cells generate antibodies with a range of different affinities

stronger affinities might be more strongly selected but still have a range in general which can be useful if pathogen and antigen evolve such that previously low affinity could become the high affinity

54
Q

name the 5 ways that antibodies contribute to the immune response

A

neutralisation

chemotaxis

opsonisation = enhanced phagocytosis

antibody dependent killing/cytotoxicity

trigger classical pathway of complement cascade

55
Q

how do antibodies contribute to the immune response via neutralisation

A

antibody binds to pathogen/virus/toxin and binds to/blocks interaction of that virus with a target cell (or toxin with receptor)

56
Q

how do antibodies contribute to the immune response via chemotaxis

A

recruits immune cells to the site of infection

57
Q

how do antibodies contribute to the immune response via opsonisation

A

complement coats the infectious agent/pathogen to make them more recognisable to the immune system

antibodies do the same thing as the Fc constant can be bound with special receptors on cells of immune system

58
Q

how do antibodies contribute to the immune response via antibody-dependent killing

A

once the antibodies have coated something such as bacteria/virus/another cell infected by virus, then can drive the killing by a range of cell types including the natural killer cells

59
Q

describe the chain of events when an antigen binds to the cell surface antigen receptor surface immunoglobulin to when the B cell becomes a antibody forming cell

A

antigen binds to a cell surface antigen receptor surface immunoglobulin

CD79 signal transduction molecules help drive signal that tell cell that the specific antigen receptor has bound an antigen so need to turn the cell on

generates an internal signal

causes the differentiation of antibody forming cells and the production of antibodies

60
Q

describe the chain of events when an antigen is presented to the cell surface antigen receptor T cell receptor to when the T cell becomes a cytotoxic/helper cell

A

antigen is presented to the cell surface antigen receptor T cell receptor

CD3 transduction molecules help drive signal that tell cell that the specific antigen receptor has bound an antigen so need to turn the cell on

generates internal signal

becomes cytotoxic/helper T cells

61
Q

what is the signal transduction molecule involved in the B cell

A

CD79

62
Q

what is the signal transduction molecule involved in the T cell

A

CD3

Principles of Medicine (POM) (11 decks)

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