Lecture 12 and 13, Adaptive immunity Flashcards
(132 cards)
1
Q
What recognizes foreign material and proliferate
A
lymphocytes
2
Q
What are the 3 characteristics of adaptive immunity
A
molecular specificity, memory, tolerance
3
Q
What is molecular specificity
A
can differentiate among unlimited numbers of infecting agents
4
Q
Memory has a stronger response to _______
A
re-exposure
5
Q
What does vaccination rely upon
A
memory
6
Q
what is tolerance
A
Must distinguish between what is healthy self and what is dangerous
7
Q
What is the first response to an antigen called
A
primary response
8
Q
the stronger _______ reponse results with subsequent exposure
A
secondary
9
Q
What is humoral immunity
A
Anti-body mediated, eliminates extracellular antigens
10
Q
What cell does humoral immunity involve
A
B cells
11
Q
What is cell mediated immunity
A
antigens residing within a host cell
eg virus-infected cells, cancer cells
12
Q
What cell does CMI involve
A
T cells
13
Q
What is naive lymphocyte
A
has never encountered antigen, cannot react until it received confirming signals
14
Q
What is activated lymphocyte
A
Has received confirming signals from dendritic cell expressing cognate antigen, proliferates, deifferentiates
15
Q
effector lymphocyte
A
short-lived, primary response
16
Q
memory lymphocyte
A
long-lived, activated more quickly to provide secondary response
17
Q
in humoral immunity, activated B cells differentiate into _______ cells in response to extracellular antigens
A
plasma
18
Q
activated B cells produce _______
A
antibodies
19
Q
The stem of the antibody is what
A
red flag, marks bound antigen for elimination
20
Q
What does B cell receptor do?
A
recognizes antigen by membrane bound antibody, must receive T cell signal to proliferate for same antigen
21
Q
CMI
what eliminates antigens?
A
two subsets of T cells
22
Q
CMI
what cell destroys corrupted host cells?
A
cytotoxic T cell
23
Q
CMI
What cell directs/assists adaptive immune responses
A
helper T cell
24
Q
CMI
both T cells have _______ analagous to BCR
A
T- cell receptors TCR
25
TCR does NOT
recognize free antigen, antigen must be presented by body's own cell
26
_______ and _______ must be activated before they can multiply
helper T cells and cytotoxic T cells
27
_______ cells are responsible for T cell activation
dendritic
28
CMI
Once activated, T cell proliferates
forms _______ or _______
Effector helper T cells or effector cytotoxic T cells
29
Tc cells respond to _______
intracellular antigens
30
Tc cells induce cell to undergo _______
apoptosis
31
T h cells activate _______
B cells, macrophages, produce cytokines to direct and support other cells
32
regulatory T cells do what
stop immune system from overreacting and responding to harmless substance
33
_______ cells play a crucial role in activation of naive Th and Tc cells
dendritic
34
Where do dendritic cells reside?
peripheral tissue
35
Dendritic cells can send extensions between what?
epithelial cells of mucosal barriers and sample material in respiratory tract and lumen of intestine
36
What do toll like receptors do?
recognize pathogens
37
if TLR detects pathogen, what happens?
cell takes up more material
38
TLRs travel to _______, matures
secondary lymphoid organs
39
TLRs produce _______ signaling danger
co-simulatory molecules
40
TLRs present antigens on both _______
MHC class I and II
41
T cell is activated by the dendritic cell expressing what?
cognate antigen, as part of MHS calls I or class II and co-simulatory molecules
42
only T cells which can respond to _______ are allowed to mature
antigens presented by class I or class II
43
B cells and T cells have _______receptors
Membrane bound
44
_______ does not recognize free antigen, must be presented by body's own cells
TCR
45
lymphatic system brings populations of lymphocytes in contact with _______
antigens
46
lymphatic vessels carry
lymph
47
Lymph contains antigens from _______
tissues
48
lymph flows through _______ before emptying back in circulatory system
lymph nodes
49
inflammatory causes what to happen to lymph
more fluid to enter tissues, increases antigen containing fluids entering lymphatic system
50
Primary lymphoid organs include
bone marry, thymus
51
_______ reside in bone marrow, give rise to all blood cells
hematopoietic stem cells
52
_______ cells mature into bone marrow
B cells
53
_______ cells migrate to thymus and mature
T cells
54
once mature, lymphocytes gather in _______ and wait to encounter antigen
secondary lymphoid organs
55
What are secondary lymphoid organs
lymph nodes, spleen, tonsils
56
_______ allow sampling of intestinal contents
peyer's patch
57
peyer's patch sample intestinal contents via what cells/
M cells, dendritic cells
58
Peyers patch is part of
MALT
mucosa associated lymphoid tissue
59
_______ prevents microbial invasion via mucous membrane
mucosal immunity
60
lymphoid tissues under skin are
SALT
skin associated lymphoid tissue
61
Antigen comes from
Antibody generator
62
What are T-dependent antigens
B cells requires confirmation from Th cells to be activated, protein componenet
63
T independent antigens can activate B cells without
Th cell help, include Lipopolysaccharide and molecules with repeating subunits
64
Antigen that elicit immune response is
immunogenic
65
_______ are more immunongenic than nucleic acids or lipids
proteins
66
_______ are usually not immunogenic
small molecules
67
what are epitopes
distinct regions of molecules
68
epitopes can be stretches of 10 _______
amino acids
69
Bacterial cells posses many different _______
epitopes
70
antibodies are also called
immunoglobins
71
what shape is an antibody
Y shaped
72
On an antibody, what are the two identical arms called
Fab regions
73
What do fab regions do
bind antigen
74
What is the stem of the antibody called
Fc region
75
What part of antibody can be crystallized
Fc region
76
Light chains have how many amino acid folds
2
77
Heavy chains have how many amino acid folds
4
78
Fork of Y is _______ region
flexiible hinge
79
_______ bonds join heavy, light chains and two halves
Disulfide
80
_______ region at ends of fab regions accounts for specificity
variable region
81
Antigen binding site attaches to _______
epitope
82
constant region inclues
Fc and two Fab regions
83
Neutralization
prevents toxins, viruses from binding
84
opsonization
enhancement of phagocytosis
85
complement system activation
classical pathway
86
immobilization and prevention of adherence
binding to bacterial flagella or pili interferes
87
cross linking
two arms of antigen bind separate antigens
88
antibody dependent cellular cytotoxicity (ADCC)
targets cell for destruction by natural killer (NK) cells
89
five major classes of immunoglobulin
igM, igG, igD, igE
90
IgM is produced when
during primary response
91
IgM is produced in response to ______
T-independent antigens
92
IgM is what type of subunit?
pentamer, 5 subunits
93
Pentamers ______ very effecitvely
aggregate
94
Larger size of IgM prevents what
crossing from bloodstream to tissue
95
IgM is primary role is
Bloodstream infection
96
which antibody is the most abundant?
IgG
97
igG provides
longest term protection
98
How does igG protect?
via neutralization, aggregation, opsonization, complement activation
99
IgG is transported across ______ to ______
placenta to fetus's bloodstream
100
What does maternal IgG do?
protects fetus and newborn?
101
IgG is found in ______
colostrum (first breast milk)
102
IgG is absorbed by newborn's ______
intestinal tract
103
most IgA is a dimer which is
secretory IgA (sIgA)
104
IgA is important for what?
mucosal immunity
105
how does IgA protect?
via neutralizing toxins, viruses, interfering with attachment of microbes
106
What is IgA produced by
Plasma cells of MALT
107
What antibody is the least common?
IgD
108
What is IgD involved with?
development and maturation of antibody resposen
109
How prevalent is IgE?
barely detectable in serum, tightly bound in Fc region
110
What do antigens do to IgE?
they bind two adjacent IgE molecules carried by mast cell
111
IgE is important in eliminating what
parasitic worms
112
How is allergies related to IgE?
basophils and mast cells release chemicals when IgE binds to harmless foods and cause reaction
113
Colonal selection applies to what cell?
B cells and T cells
114
lymphocytes residing in secondary lymphoid organs wait for ______
Antigen with correct epitope
115
immature lymphocytes
lack fully developed antigen specific receptors
116
Naive lymphocytes
have receptors, have not yet encountered appropriate antigen
117
activated lymphocytes
have bound antigen and received confirmation, are able to proliferate
118
effector lymphocytes
descendents of activated lymphocytes:
plasma cells, Tc cells, Th cells
119
Memory lymphocytes
long-lived descendants of activated lymphocytes; responsible for rapid secondary response if antigen is encountered again
120
B cell is activated by ______ antigens
T-dependent
121
the fragments of the antigen from B cell receptor is delivered to ______
MHC class II molecules for inspection by Th cells: antigen presentation
122
If T cell receptor binds a fragment, T cell activates B cell with cytokines and initiates ______
Clonal expansion
123
If no Th cell recognizes peptides, B cell becomes ______
Anergic
124
What does anergic result in
tolerance to antigen
125
how many days does it take for the antibody accumulation after first exposure
10 to 14
126
in primary response, ______ cells continue proliferating and differentiating in presence of antigen, so antibody titer increases
Activated B cells
127
in primary response, ______ cells undergo changes that result in production of more effective antibodies
Proliferating B cells
128
What is affinity maturation
spontaneous mutation occurs in multiplying B cells resulting in changes in B cell receptor
B cells that bind antigen longest proliferate
129
What is class switching
Plasma cells normally secrete IgM, Th cells induce B cells to become plasma cells that secrete other antibody classes
130
B cells in lymph nodes switch to
IgG
131
B cells in MALT switch to
IgA
132
After class switching, ______ cells are formed
memory
