Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Medicine Unit 3 > Adaptive immunity > Flashcards

Adaptive immunity Flashcards

1
Q

adaptive immunity basic

A

specific to a pathogen
slower

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

humoral immunity within adaptive

A

proteins dissolved in serum, plasma nd tissue fluid
antibodies

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

cells involved in adaptive immunity

A

b cells
antibodies
t cells
effector t cells
memory t and B cells

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

where do the 3 main types of lymphocyte originate from

A

common lymphoid precursor

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

lymphocytes that make ups the adaptive immune system

A

T and B cells
recognise specific antigen
proliferate and differentiate to mediate effector function
provide immunological memory

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

antigens

A

parts of pathogens (often proteins or parts of proteins) to which T and B cells respond
they respond via their antigen receptor
which is highly specific i

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

lymphocyte antigen receptors

A

unique antigen receptor on each lymphocyte
large diversity of specificities in T and B cell populations

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

what is antigen recognition by a specific lymphocyte linked to

A

activaiton
proliferation
differentiation
results in many specific cells with effector function

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

T cell responding simple

A

cytotoxicity
help of other cells
regulation

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

B cells responding simple

A

antibodies (neutralisation, opsonisation, activation of complement)

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

memory T and B cells

A

long-lived and triggers a quicker and more effective immune response on second infection with the same pathogen

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

primary lymphoid organs

A

bone marrow and thymus
where lymphocytes develop and mature from bone marrow-derived stem cells

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

secondary lymphoid organs

A

lymph nodes, spleen, MALT
site where adaptive immune responses are coordinated

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

T cells

A

originate in the bone marrow
mature in the thymus
express antigen receptor known as T cell receptor (TCR)
TCR recognises peptides presented to it
in the right conditions, T cell breaking TCR recognising the presented peptide becomes activated, proliferates and differentiates into lots of cells which have effector function

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

5 steps of T cell immune response

A

diversity
specific recognition
activation
proliferaiton and differentiation
response by effector cells

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

TCR diversity

A

genetic mechanism evolved to create diversity of specificities in the adaptive immune system

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

schematic structure of the T cell receptor

A

heterodimeric receptor
2 different chains, alpha and beta

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

with diversity why are many TCR not suitable

A

some useless: don’t bind peptides presented by molecules on your cells
dangerous: bind self-peptides very strongly

cells bearing these TCR die during T cell development in the thymus

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

T cell specific recognition

A

antigen must be broken down into peptide fragments
epitope peptide binds to a self molecule, MHC molecule
TCR binds to complex of MHC molecule and epitope peptide

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

2 main types of T cells

A

helper T cells
cytotoxic T cells

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

helper T cells: MHC, co-receptor and function

A

MHC 2 (presents antigen only on professional antigen presenting cells)
CD4
produces cytokines to activate others immune cells
express surface molecules to affect other cell types

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

cytotoxic T cells: MHC, co-receptor and function

A

MHC 1 (presents antigen on all body cells)
CD8
]kill virus-infected cells directly

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

which T cell is in the image

A

CD4 T cell

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

which T cell is in the image

A

CD8 T cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
example of an antigen presenting cell
dendritic cell it is professional key role in initiating adaptive immunity by linking innate to adaptive
26
key features of dendritic cells
specialised for antigen uptake and presentation mature when stimulated by PAMPs and DAMPs
27
how are dendritic cells specialised for antigen uptake and presentation
dendritic cells present antigen open both MHC class 1and 2 sp they can activate CD8 and CD4 T cells
28
how are dendritic cells matured when stimulated by PAMPs and DAMPs
cause them to express high levels of molecules required to activate naive T cells migrate to secondary lymphoid tissue which is a specialised structure for initiation of adaptive immunity
29
how are professional APC specialised to initiate adaptive immunity
provide all the signal necessary to activate naive T cells express MHC 1 and 2 so can activate CD8 and CD$
30
nucleated cells, MHC class?
all express MHC class 1 means when infected they can present pathogen-derived antigens and be targets of CD8 cytotoxic T cells
31
other examples of professional APC
macrophages and B cells
32
what are MHCs and HLAs
MHC: major histocompatibility complex HLA: human leukocyte antigens
33
large proteins antigens
digested into small peptides, epitopes of the antigen
34
where are peptide epitopes bound to
in the peptide-binding groove of the HLA encoded by MHC genes
35
HLA in MHC class 1
A,B and C
36
HLA in MHC class 2
DP, DR and DQ
37
which MHC class is this
class 1 expressed by all nucleated cells binding groove holds short peptides, 8-10 amino acids
38
which MHC class is this
class 2 expressed by APCs binding groove holds larger peptides, 13-17
39
mhc genes
polygeny polymorphism
40
polygeny
several MHC genes
41
polymorphism
variation in population- protection at population level
42
MHC 1 presentation
infection of body cell by virus virus is chopped up by the proteasome new viral particles are synthesised in the ER antigens landed onto the MHC 1 in the endoplasmic reticulum activates CD8 cytotoxic T cells
43
MHC 2 presentations
phagocytosis of pathogen by antigen presenting cell pathogen is chopped up by phagolysosomes antigens loaded onto MHC 2 in the phagolysosome activates CD4 helper T cells
44
signals that naive T cells need to be activated
antigen binding to the T cell receptor costimulation cytokines
45
first signal of T cell
peptide-MHC : TCR if there is a recognition then an immune synapse forms
46
second signal of the T cell
costimulation B7: CD28
47
third single of T cells
cytokines APC produces cytokines that instruct the T cell to differentiate into the right type of effector T cell to destroy the pathogen
48
outcomes of the activation of T cells
T cell activation, proliferation and differentiation lots of cells ready to destroy pathogen directly or indirectly
49
what do effector cells not need
co-stimulation to exert their function
50
what are the types of t helper cells
Th1 Th2 Th17 Tfh T reg
51
Th1
polarising cytokine: IL-12 transcription factor: T-bet cytokine produced: IFN gamma primary function: activate macrophages
52
Th2
polarising cytokine: IL-4 transcription factor: GATA3 cytokines produced: IL4,5 and 13 primary function: activate eosinophils and mast cells, alternative macrophage function
53
th17
polarising cytokine: IL-6 and 21 transcription factor: ROR gamma T cytokines produced: IL-17 and 22 primary function: enhance neutrophil response
54
Tfh
polarising cytokine: IL-6, TGF beta, IL-23 transcription factor: Bcl6 cytokines produced: IL-21 (and IL-4 or IFN gamma) primary function: activate and mature B cells
55
T reg
polarising cytokine: TGF beta transcription factor: FoxP3 cytokines produced: IL-10, TGF beta primary function: suppress other effector T cells
56
what can CD8 cytotoxic T cells do after recognition
can kill virus infected cells
57
cytotoxic T cells killing mechanism
killing is specific, requires the specific peptide-MHC: TCR interaction killed by: perforin/granzyme or Fas:FasL interaction
58
fas:FasL interaction
FasL is expressed by cytotoxic T cells and Fas is expressed by the target cells FasL- Fas interaction activates FADD then pro-caspase 8 in the target cell during apoptosis, caspases are activated activation of cascades results in orderly destruction of the target cell
59
what are caspases
cysteine proteases that cleave aspartic acid
60
granzymes/ perforin
exocytosis of lytic granules at the immune synapse attack of the target membrane: perforin polymerise forming cylindrical pores in the target cell, granzymes enter triggering of caspase cascade, leading to DNA cleavage and cell death
61
CD4 T cell help of CD8 T cell ctivaiton
activated CD4 T cells expresses CD40L ligand on its surface induces expression of IL-2 cross primes CD8 by enhancing APC activation stimulation of APC through CD40 increases B7 and CD40, co-stimulate naive CD8, increase APC production of IL-12
62
cross presentation
how antigen taken up by phagocytosis gets loaded onto MHC 1 important for anti-tumour and anti-viral immunity
63
b cells
produced in the bone marrow and exit with the recombined antigen antigen receptor is the B cell receptor B cells with BCR specific to the antigen become activated, proliferated and differentiate into effector cells plasma cells make antibodies
64
stages of B cell immune response
diversity specific recognition activation proliferation and differentiation effector cells and memory cells
65
what is in the image
surface antibody
66
what is in the image
soluble antibody
67
rearrangement of immunoglobulin genes
rearrangement at heavy and light lg chain loci nucleotides are added or removed at random between the segments as they come together in the recombined gene
68
B cell receptors
bind directly to the antigen even if they are still attached to the pathogen
69
B cell 3 signals
BCR signalling and uptake co-stimulation cytokines
70
B cell first signal
antigen activates the B cell via the BCR it is taken up, processed and presented on MHC 2 to a specialised CD4 t helper cell
71
B cell second signal
CD40: CD40L
72
B cell third signal
cytokines produced by the T cell intersect the B cell to produce certain antibody type
73
B cell activation
B cell is activated, proliferates and differentiated into plasma cells and memory cells IgM is the first antibody class type to be made
74
what is the first antibody class type to be made
IgM
75
plasma cells
produce and secrete antibody cytokines produced by the T cell direct class-switching of B cells
76
what must the classes of antibodies have
a different heavy chain constant region, region linked to the function
77
variable region q
determines antigen specificity
78
constant region
determines antibody class finds Fc receptors
79
what are the 5 types of antibodies
IgG IgE IgD IgA IgM
80
IgG
multi-purpose high affinity crosses the placenta
81
IgE
parasite responses and allergies
82
IgD
basophils
83
IgA
secreted at mucus sites
84
IgM
first to be made on encounter with antigen
85
IL-4 role of regulating expression of antibody classes
inhibits: IgM, IgG3 and IgG2a induces: IgG1, IgE
86
IL-5 role of regulating expression of antibody classes
augments production of IgA
87
IFN- gamma role of regulating expression of antibody classes
inhibits: IgM, IgG1, IgE induces: IgG3, IgG2a
88
TGF- beta role of regulating expression of antibody classes
inhibits: IgM, IgG3 induces: IgG2b, IgA
89
IL-21 role of regulating expression of antibody classes
induces: IgG3, IgG1, IgA
90
what are the functions of antibodies
neutralisation opsonisation complement activation NK cell sensitisation mast cell, eosinophil and basophil sensitisation
91
neutralisation
IgA and IgG antibodies that bind bacterial toxins and virus particles stop them binding receptors on host cells and prevent damage to tissue
92
opsonisation
IgG antibodies that bind to pathogens phagocytes recognise bound antibody via Fc receptor trigger phagocytosis and killing
93
complement activation
IgM and IgG antibodies that bind pathogens and activate the complement pathway trigger formation of membrane attack complex and killing of pathogen
94
NK cell sensitisation
IgG antibodies binds antigens on the surface of target cells Fc receptors on NK cells recognise bound antibody cross-linking of Fc receptors signals the NK cell to kill the target cell target cell dies by apoptosis
95
mast cell sensitisation
mast cells express Fc receptors recognising IgE crosslinking of the antibodies by antigen causes mast cell degranulation releasing mediators such as histamine
96
eosinophil sensitisation
regonise UgE bound to parasites and release granules to kill the parasites
97
basophil sensitisation
recognise IgD activating anti-microbial and pro-inflammatory mechanisms

Medicine Unit 3 (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions