exam 4 Flashcards
1
Q
What cells does adaptive immunity have?
A
t cells and b cells
2
Q
Anything that elicits an adaptive immune response (they are pieces of pathogens)
A
antigen
3
Q
the specific portion of an antigen that triggers an immune response
A
epitopes
4
Q
The more_____ in adaptive immunity, the bigger the response.
A
epitope
5
Q
The part of the antibody that binds to an epitope
A
paratope
6
Q
The ability of an antigen to provoke an adaptive immune response; based on size and complexity of antigen
A
immunogenicity
7
Q
What elicit the greatest immune response in immunogenicity?
A
protein epitopes
8
Q
Molecules that are too small to elicit an immune response
A
haptens
9
Q
What are B cells?
A
plasma cells
10
Q
What are T cells?
A
Helper cells, cytotoxic cells, regulatory cells
11
Q
where is B cell maturation in the body?
A
bone marrow
12
Q
Where is t cell maturation in the body?
A
Thymus
13
Q
What are primary lymphoid organs?
A
bone marrow and thymus
14
Q
What is negative selection in lymphocyte maturation?
A
T cells and B cells are deleted due to lack of receptor
15
Q
What is positive selection of lymphocyte maturation?
A
Selection of remaining cells that can leave the thymus or bone marrow and travel to secondary lymphoid organs
16
Q
What are secondary lymphoid organs?
A
Spleen, lymph nodes, appendix, intestine, tonsils, MALT (mucosal associated lymphoid tissue)
17
Q
What is clonal selection?
A
- Armed t cells reside in secondary lymphatic organs
- Each TC receptor is programmed to bind to a specific antigen
- Mature lymphocyte is presented with and binds to its receptor specific antigen
- Cloning of single type of T-cell
- Army of clones is built to target one specific antigen
- Cells may differentiate into effector cells or memory cells.
18
Q
What is cell-mediated immunity?
A
T cells eliminate pathogen
19
Q
What is humoral immunity?
A
Antibody-mediated response produced by B cells
20
Q
what do cytotoxic T cells do?
A
Directly attack antigens by phagocytosis
21
Q
What do memory t cells do?
A
Respond to the same antigen upon future exposure
22
Q
What do Helper T cells do?
A
Regulate activation of T cells and activate b cells to produce antibodies
23
Q
What do regulatory t cells do?
A
Regulate B and T cell activity
(suppress immune response when done)
24
Q
What do B cells do?
A
secrete antibodies
25
what marker do cytotoxic t cells have?
CD8
26
What marker do T helper cells have?
CD4
27
What are APCs?
antigen presenting cells, present to t cells to identify pathogen
28
What does CD8 cytotoxic T cells interact with?
MHC 1
29
What does CD4 helper T cells interact with?
MHC II
30
What do apc's do?
phagocytize, process, and present
31
What does class 1 MHC do?
binds intracellular targets; interacts with CD8; binds to any NUCLEATED body cell
32
What does class 2 MHC do?
Binds phagocytized targets; on the surface of APC's; interact with CD4
33
what happens when CD4 cells are activated?
Produces large numbers of helper t cells that secrete cytokines for immune response
34
What redirects the presentation of APCs to cytotoxic T-cells?
TH1
35
What activates B-cells
TH2
36
What is the function of CD8 T cells?
find and destroy abnormal cells (must display MHC 1 antigen)
37
What is the cytotoxic T cell response when it finds a target antigen?
Secretes perforin to destroy target cells, secretes lymphotoxins to kill, activates gene in target cell to induce apoptosis
38
What is sensitization?
the process by which a lymphocyte (usually a B cell) first encounters its specific antigen and becomes activated.
39
What does IgD do?
it binds with correlating antigen, phagocytizes it, and presents it on MHC2 on outside
40
What secretes mass amounts of antibodies?
plasma cells
41
What cells remain inactive during the first exposure and then after another exposure, they divide and differentiate into plasma cells
Memory B cells
42
What is the antibody structure?
glycoprotein
43
what immunoglobulin is the Main form of antibodies in circulation: production
increased after immunization; secreted during
secondary response
IgG
44
what immunoglobulin is the Main antibody type in external secretions, such as
saliva and mother’s milk
IgA
45
what immunoglobulin is Responsible for allergic symptoms in immediate
hypersensitivity reactions
IgE
46
What immunoglobulins Function as antigen receptors on lymphocyte surface
prior to immunization; secreted during primary response
IgM
47
what immunoglobulins Function as antigen receptors on lymphocyte surface
prior to immunization;
IgD
48
What is agglutination?
Antibodies attach to multiple antigens (clumping)
49
What immunoglobulin is best for agglutination?
IgM
50
What is neutralization in an antibody response?
Antibodies neutralize the sites on a virus or toxin, prevents attachment of cells or toxins
51
Which immunoglobulins are best for neutralization?
IgG, IgM, IgA
52
What is opsonization?
Coats antigens eliciting more efficient phagocytosis
53
Macrophages and Neutrophils have _______ ____ receptors to bind antibody
IgG Fc
54
what does the compliment system do in antibody responses
Opsonization and cell lysis
55
what does ADCC do?
trigger cell lysis
56
when you go from IgM to IgG, what is it called?
class switching
57
What happens during the primary antibody response?
Antibodies increase slowly (1-2 weeks for peak), IgM are first to appear in blood but then replaced by IgG, if no more exposure, antibodies decline
58
What happens during secondary antibody response?
Memory B cells maintained (can live up to 20yrs), If consecutive exposure, memory b cells quickly differentiate into plasma cells (don't need TH activation), plasma cells produce more destructive IgG antibodies, prevents repeat infection
59
what is recombination in variation?
it changes gene structure to target specific pathogens
60
what are the reasons for immune disorders?
Born with weak immune system, contract disease that weakens immune system, auto-immune disease, overactive immune system (allergies)
61
What are inherited genetic disorders that cause chronic increased susceptibility to infection
Primary immunodeficiencies (PIDD)
62
What are PIDD characteristics?
Rare diseases, variety of phenotype, 50-60% are B-cell disorder, 5-10 are t cell disorders
63
What is the most severe Immunodeficiency, no B or T cell responses?
SCID (severe combined immunodeficiencies
64
What is acquired immunodeficiency?
Common infections can temporarily suppress the immune system
65
HIV infection, chemotherapy, measles, and flu can cause what immunodeficiency?
acquired
66
how does cancer escape being destroyed
They escape recognition and destruction of Cytotoxic t cells and NK cells
67
What occurs when an autoantibody or autoimmune T-cell damages tissue; breaks down in self tolerance?
Autoimmune disorders
68
What is an organ specific autoimmune disease?
Type 1 diabetes (t cells attack insulin)
69
What is a systemic autoimmune disease?
lupus (autoantibodies against many differnt antigens)
70
What are mechanisms of autoimmune disease?
Defect in negative selection of self reacting lymphocytes during maturation,
Triggered by microbial antigen that has an epitope that resemble self
Trauma can expose hidden antigens that trigger response (DNA
71
what is an undesired immune response to non-threatening antigen?
Hypersensitivities
72
What is Type 1 hypersensitivity mediated by?
IgE (allergies)
73
What is Type 2 hypersensitivity mediated by?
Antibody mediated cytotoxic (blood transfusion rejection)
74
What is Type 3 hypersensitivity mediated by?
Soluble antibody-antigen complexes
75
What is Type 4 hypersensitivity mediated by?
Delayed cell mediated (transplant rejection)
76
all hypersensitivities are _____mediated
antibody (they must be exposed first)
77
Type 1 uses what cells?
Mainly mast cells, some basophils
78
What does an initial exposure to type 1 generate?
IgE
79
Antigen presenting cells present with which MHC?
2
80
What cell does MHC 2 present to?
CD4 T helper cell
81
What presents MHC 1?
nucleated cell
82
What receptor does B sensitization use?
IgD
83
What are 3 APCs?
macrophage, dendritic, B cell
84
What is the process after a first hypersensitivity reaction? (all hypersensitivities)
APC presents toxin, TH CD4 recognizes, sensitization of B cell by CD4, B cell becomes plasma, plasma secretes IgE, IgE binds to mast cells that are primed
85
With Type 2 hypersensitivity, once exposed, what happens with the antibodies?
it binds directly to self cell antigens
86
What cells do Type 2 hypersensitivity work with after exposure?
Macrophage or NK cell
87
What do macrophages and NK cells do to antigen in Type 2 hypersensitivity?
Causes cell lysis
88
Which hypersensitivity stimulates the complement system and opsonization?
Type 2 hypersensitivity
89
What is an example of hypersensitivity type2?
blood recipient problems, penicillin with RBC's, transplants
90
what is an example of type 1 hypersensitivities?
allergies to bees, mosquitoes, peanuts
91
What hypersensitivity has antibodies that bind to soluble antigens and form insoluble immune complexes that deposit basement membranes?
Type 3 hypersensitivity
92
Which hypersensitivity has formed antibodies that bind freely (not attached to cell) to antigen/antibody complexes (agglutination)
Type 3 hypersensitivity
93
Where is agglutination deposited into?
tissues
94
What hypersensitivity elicits an innate immune response (inflammation) and tissue damage by leukocytes?
Type 3 Hypersensitivity
95
What are examples of type 3 hypersensitivities?
Serum antivenoms, inhaled particles, group A strep, monoclonal antibodies
96
What is the only T cell mediated reaction, doesn't do antibody mediated?
Type 4 hypersensitivity
97
With Type 4 hypersensitivity, what does a second exposure do?
memory cells activate Cytotoxic T cells/macrophages
98
With type 4 hypersensitivity, once you are exposed, how long before you get a response?
48-72 hours
99
What are examples of Type 4 hypersensitivities?
Contact dermatitis, poison ivy, metal allergies
100
What are treatments for Hypersensitivities?
Antihistamines, anti-inflammatory, epinephrine, desensitization therapy
101
What hypersensitivity is organ transplant rejection?
Type 2
102
Why does organ transplant rejection happen?
Self-MHC does not induce binding
103
What is acquired by passing or transferring antibodies from another source?
Passive immunity
104
Which immunity is antibodies crossing the placenta or passing through breast milk?
Naturally Acquired Passive Immunity
105
Which immunity is the administration of antibodies infused to combat infection?
Artificially induces passive immunity
106
What is an example of passive immunity?
rabies virus antibodies
107
What antibodies does artificial passive immunity give you?
Monoclonal antibodies
108
Which immunity is when your body makes its own antibodies?
Active immunity
109
Which active immunity develops after exposure to antigens in the ENVIRONMENT? (infection)
Naturally acquired active immunity
110
Which active immunity has antigen administration in order to prevent disease? (vaccines)
Artificially induced active immunity
111
What is the immunogenic material used to induce artificially acquired active immunity?
Vaccine
112
The method of inoculation used for thousands of years?
Variolation
113
What is an example of variolation?
smallpox
114
What is a live attenuated vaccine?
Contains whole agent in weakened or less virulent form
115
What are examples of Live attenuated vaccine?
Mumps, measles, rubella, chickenpox
116
What are advantages of live attenuated vaccine?
Most closely mimics a natural infection
117
What are disadvantages of Live attenuated vaccine?
Not good for immunocompromised, Could cause reversion
118
What is inactivated vaccines?
Pathogen is dead
119
What are the advantages of Inactivated vaccines?
Can't reproduce so can't cause disease, no reversion
120
What are disadvantages of inactivated vaccines?
Requires boosters, patients may not follow up
121
What are subunit vaccines?
Use genetic engineering to produce pathogens fragments with high immunogenicity
122
What is toxoid vaccine?
Use of inactivated toxins to protect from a microbial toxin
123
What is an adjuvant?
A substance that enhances general immune function (given with toxoid vaccine)
124
What are nucleic acid vaccines?
Uses synthetically generated nucleic acid with sequence that matches key genes of the pathogens (mRNA)
125
What is the benefit of nucleic acid synthesis?
Faster, cheaper, induces both humoral and cellular immunity
126
What are the negatives of mRNA over DNA?
more fragile, cold storage,
127
Why is there vaccine hesitancy?
Inflammatory response, allergic response, effectiveness
