Immune-1 Flashcards
1
Q
what is the immune system (basic)
A
collection of cells, tissues and molecules that protects the body from pathogens, toxins and cancerous cells
2
Q
what are 3 things that happen in a normal immune response
A
- elimination of pathogen
- destruction of transformed cells
- neutralization of toxins
3
Q
what are 4 things that happen in an abnormal immune response
A
- immunodeficiency (AIDS)
- hypersensitivity (allergies)
- autoimmunity (lupus)
- cancer
4
Q
is the innate immune or adaptive/acquired faster
A
innate
5
Q
is the innate immune or adaptive/acquired the first line of defence
A
innate
6
Q
is the innate immune or adaptive/acquired more specific
A
adaptive/acquired
7
Q
is the innate immune or adaptive have memory
A
adaptive/acquired
8
Q
what is innate immunity good for
A
immediate protection against majority of infections, primitive, does not require priming
9
Q
what initiates the innate immune system
A
engagement of PRRs ( pattern receptor recognition )
10
Q
what do pattern receptor recognition recognize
A
things common to pathogens that we dont have, like bacterial wall. this is how we identify them
11
Q
is pattern receptor recognition specific
A
no not specific to the invading pathogen
12
Q
what are 6 components of the innate immune system
A
- physical barriers
- phagocytes
- acute phase proteins
- complement system
- NK cells
- esosinophils, basophils and mast cells
13
Q
what is an example of acute phase proteins
A
opsonins
14
Q
what is an example of physical barriers
A
mucosal epithelia and skin
15
Q
what is 2 example of phagocytes + what are they
A
neutrophils and macrophages, they engulf pathogens
16
Q
how do mucosal epithelia and skin help protect us
A
- produce mucins to prevent pathogen attachment and entry
- produce antimicrobial peptides induced by engagement of PRRs
17
Q
what happens after initial contact of phagocytes with pathogens
A
initiate multiple antimicrobial mechanisms
18
Q
what are opsonins
A
host products of the acute phase response and the complement systems (make them more attractive to phagocytes)
19
Q
what can opsonins facilitate
A
phagocytosis
20
Q
what can facilitate phagocytosis
A
opsonins
21
Q
what is complement
A
series of plasma enzymes and proteins activated in a cascading fashion
22
Q
what are 3 consequences of complement activation
A
- recruitment of phagocytes
- opsonization
- direct killing (MAC attack)
23
Q
how does complement cause recruitment of phagocytes
A
through release of proteolytic fragments with chemotactic activity
24
Q
how does complement cause opsonization
A
through covalent attachment of C3 fragments
25
how does complement cause direct killing
through formation of membrane-attack complex (MAC attack)
26
what are the 3 main categories of roles in complement in innate immunity
chemotaxis, opsonization, bacterial lysis (MAC)
27
what does MAC stand for
membrane-attack complex
28
what are the 2 main groups of lymphocytes
T and B cells
29
what does T cell mean
thymus derived lymphocytes
30
what does B cell mean
bone marrow derived lymphocytes
31
what % of the peripheral blood lymphocytes and T and B cells
80-95%
32
what differentiates the lymphocytes (3)
- specific sets of surface markers (receptors)
- their location in lymphoid organs
- their function
33
what defines types of T cells + what are the types
their receptors
TCR- αβ
TCR- γδ
34
what receptors do TCR- αβ express
CD4 or CD8 receptors
35
what are CD4 expressing T cells
T-helper cells
36
what are CD8 expressing T cells
cytolytic T cells
37
what do T-helper cells have on surface
CD4
38
what do cytolytic T cells have on surface
CD8
39
what do T-helper cells recognize
antigens with MHC class 2 molecules
40
what do cytolytic T cells recognize
antigens with MHC class 1 molecules
41
do TCR- αβ or TCR- γδ express CD4 or CD8
TCR- αβ
42
do TCR- αβ express CD4 or CD8
yes both
43
do TCR- γδ express CD4 or CD8
no
44
which cell recognizes antigen with MHC class 2 molecules
CD4 t helper cells
45
which cell recognizes antigen with MHC class 1 molecules
CD8 cytolytic T cells
46
where do t cells mature
in the thymus
47
which type of t cells die in the thymus
the ones that are recognizing our own antigens (autoreactive)
48
where do pluripotent stem cells become pre t cells
in the bone marrow
49
where do t cells recognize antigens
in the periphery
50
what are b cells responsible for
secrete their antigen receptors as antibodies (antibody production)
51
what do b cells express on their surface
antigen receptors/ B cell receptors (BCRs)
52
what are b lymphocytes
precursors of the immunoglobulin-producing cells (plasma cells)
53
do plasma cells have surface immunoglobulin
no
54
do plasma cells divide
no
55
are plasma cells found in the peripheral blood
no
56
where are plasma cells not found
in the peripheral cell
57
what dont plasma cells have on their surface
immunoglobulin
58
what dont plasma cells do
divide
59
where do pre b cells become immature b cells
bone marrow
60
what causes immature b cells to become mature b cells
antigen presentation
61
where do immature b cells become mature b cells
in the periphery
62
where do plasma cells secrete antibodies
in the periphery (often remain in organ of choice, dont circulate in the blood)
63
what does PAMP stand for
pathogen associated molecular pattern
64
what is an example of a PAMP
bacterial cell wall (humans dont have that)
65
what are PAMP based on
detection of molecular structures unique to microorganisms or damaged cells
66
when are PRRs encoded
germline
67
what are PRRs
sensors which detect molecules typical for the pathogens.
68
what is the specifics of PRRs like + explain
broad specificities which can bind to a large number of molecules with a common structural pattern
69
what does DAMP stand for
danger associated molecule pattern
70
what are DAMPs
endogenous danger molecules that are released from damaged or dying cells and activate the innate immune system by interacting with pattern recognition receptors (PRRs)
71
if DAMPs are endogenous, why does PPRs get activated
because they should only be inside the cell, so if they exit the cell, its bad
72
where do PAMPs bind
PPR
73
where do DAMPs bind
PPR or DAMP receptors
74
who expresses PPRs
innate immune cells like macrophages and dendritic cells
75
what is the difference with PAMP and DAMP
PAMP are derived from microorganisms, DAMPS are derived from host cells
76
do dendritic cells have DAMP or PRR receptors
both, although you could say that DAMP receptors are a PRR (but the slide shows both)
77
where do dendritic cells mature
in the lymph nodes and spleen
78
what happens once dendritic cells go in the lymph nodes and spleen
they initiate adaptive immunity
79
what kind of receptors are germline encoded
PRRs
80
is innate or adaptive immunity born with / germline + why
innate is germline because youre born with PRRs
81
what are dendritic cells (general)
professional antigen presenting cells
82
where are dendritic cells present
at all epithelial barriers where they watch for infection
83
how do dendritic cells monitor the tissue environment for the presence of pathogens
by using various PRRs
84
what initiates dendritic cells maturation (2)
- direct exposure to pathogens
| - specific interactions with other immune cells
85
where are dendritic cells precursors/ immature dendritic cells
they circulate in the blood and migrate from bone marrow into peripheral tissues and mucosa surfaces
86
what do PRRs cause immature dendritic cells to do
migrate into lymph nodes
87
how do immature dendritic cells recognize pathogens
via PRRs
88
what do immature dendritic cells do to antigens/pathogens
they uptake via phagocytosis them and process it into antigenic peptides
89
what happens once dendritic cells become mature
they present antigenic peptides at the cell surface by MHC calss 1 or 2 molecules
90
what does recognition of PAMPs by PRRs do (4)
Upregulate cell surface expression of co stimulatory molecules (CD80 and CD86) and cytokine and chemokine receptors + induce expression and release of cytokines and chemokines
91
where do lymphocytes circulate until they encounter their antigen
in the lymph nodes and spleen
92
what do lymphocytes recognize
antigens presented to them by APCs (like DC)
93
what do mature DCs do in the lymph nodes
release pro-inflammatory cytokines
94
what is the basic principle of the control of the adaptive immune response by the innate immunity
to establish an associated between the microbial or damage products (PAMPs and DAMPs) recognized by PRRs and the antigens recognized by lymphocytes
95
can lymphocytes recognize PAMPs and DAMPs and why
no because they only recognize them when they are presented to them (like the DC will process it first)
96
how do DCs activate naive T cells (2 things)
by presenting pathogen derived antigens with cell surface associated molecules (CD86/80)
97
what MHC class do CD4 T cells recognize
class 2
98
what MHC class do CD8 T cells recognize
class 1
99
what are 2 types of the stimulatory molecules
CD80 and CD86
100
what happens once a naive t cell gets activated
the lymphocyte differentiated into several types of effector cells, depending on the class of pathogen they recognize
101
besides the MHC and CD80/86, what other things do DCs do to activate naive T cells
they secrete cytokines
102
what is the difference with MCH 1 and 2 (general)
they antigens have different origin
103
what is the origin of antigens in the MHC 2 class
MHC 2 present antigens that were internalized via endocytosis and degraded within APCs
104
what is the origin of antigens in the MHC 1 class
MHC 1 present peptides derived from endogenous synthesized proteins (like peptides of viral or intracellular bacterial, come straight from them)
105
what signals do naive T cells require to become active
MHC/TCR (T cell receptor) and co-stimulation
106
what is necessary about the costimulatory signal
it is necessary for the synthesis and secretion of IL2
107
what are anergic t cells
they dont produce IL2 and do not proliferate on subsequent stimulations
(intrinsically functionally inactivated following an antigen encounter, but remains alive for an extended period of time in a hyporesponsive state)
108
is adaptive immune system specific
yes
109
what is the specificity of the adaptive immune system like
each lymphocyte has a receptor that recognizes a single antigenic determinant
