Chapter 12 Flashcards
1
Q
Immunity
A
Body’s ability to resist or elimate potentially harmful foreign materials
2
Q
Major targets of immune system
A
-bacteria
-viruses
3
Q
Examples of first line of defence
A
-skin
-mucous membranes
4
Q
The first lines of defence against microbes are the ____
A
Barriers
-the surfaces exposed to external environment
5
Q
What in the mouth helps combat bacteria
A
Saliva
-converts nitrate into nitrite
6
Q
Nitrite is swallowed and turned into what in the stomach
A
Nitric oxide
7
Q
Neutrophils
A
Highly mobile phagocytes
-engulf/destroy unwanted materials
8
Q
Eosinophils
A
Secrete chemicals that fight parasites
-allergic reactions
9
Q
Basophils
A
Release histamine and heparin
-allergic reactions
10
Q
Monocytes
A
Transform into macrophages
11
Q
Lymphocytes (two types)
A
B and T lymphocytes
12
Q
B lymphocytes
A
Secrete antibodies
13
Q
T lymphocytes
A
Responsible for immunity
14
Q
Two types of body immune systems
A
Innate versus adaptive
15
Q
Innate immunity
A
-nonspecific
-immediate
-nonselective
16
Q
What does it mean by- innate immune systems are nonspecific
A
This system does not recognize type of bacteria, just a common target
17
Q
What does it mean by- innate immune systems are immediate
A
This system is extremely quick to respond
-first responder
18
Q
What does it mean by- innate immune systems are nonselective
A
The system recognizes general molecular properties
19
Q
Innate immune systems are rapid but
A
Limited
-not exactly highly effective
20
Q
What three cells are important in innate defence
A
-neutrophils
-macrophages
-several plasma proteins
21
Q
Adaptive immune system
A
-specific
-takes time to initiate
-ultimate weapon
22
Q
Adaptive immune responses include (two things)
A
Antibody mediated immunity and cell mediated immunity
23
Q
What are the defences included in innate immunity
A
-inflammation
-complement system
-interferon
-NK cells
24
Q
What is inflammation
A
Brings phagocytes and plasma proteins
-nonspecific
-inactive invaders
-remove debris
-prepare for healing
25
(1) inflammation: a break in the skin introduces ____ what is the next step?
-bacteria
-activated resident macrophages engulf pathogens
-secretes cytokines and chemotaxins
26
(2) inflammation: activated mast cells release ____
Histamine
27
(3) inflammation: what is the role of histamine and cytokines
Histamine- dilates local bv and widens capillary pores
Cytokines- cause neutrophils and monocytes to stick to bv wall
28
(4) inflammation: chemotaxins attract what? What is this function
-neutrophils and monocytes
-diapedesis
29
Diapedesis
Squeezing out cells between blood vessel wall
-which migrate to infection sites
30
(5) inflammation: ____ enlarge into macrophages, which do what?
-monocytes
-macrophages AND neutrophils engulf pathogens and destroy them
31
Chemotaxis
Chemicals released to initiate migration
-helps cells to know where to go
32
Phagocytosis
Recognizes certain carbohydrates or lipids on bacterial wall
33
Phagocytosis can be aided by
Opsonins
34
Opsonins
The action of agents helping phagocytosis
-Not the name of a specific chemical
35
Oponization
An activated complement molecule from bacteria and a specific receptor from phagocyte
36
Histamine
Released from mast cells
-vasodilation
-increases capillary permeability
37
Interleukin-1, 6, TNF
-come from macrophages
-fever and inflammation
-proliferation and differentiation of B and T lymphocytes
38
Tissue repair can be ____, but what is a factor of this
Perfect, age is a factor
39
Nonregenerative tissues and lost cells are replaced with
Scar tissue
40
The complement system is composed of
Plasma proteins
-produced by liver
41
Compliment system
-cascade of chronological events (C1 to C5)
-C5 to C9 assemble membrane attack complex (MAC)
42
What is a membrane attack complex
Form of killing without phagocytosis
-embedded into surface membrane
-creates holes, making membrane leaky
-victim cell swells and bursts
43
How does a hole kill a cell
A hole stops the ability of cell to control external environment
44
What C’s initiate MAC
C5 to C9
45
Complement system is a ___ mechanism
Primary
46
Complement system as an alternative pathway
Activated by exposure to carbohydrate chains
47
Main function of complement system
Forms membrane attack complex to punch holes in victim cells
48
Complement proteins in inflammatory process promotes
-vasodilation and vascular permeability
49
Antiviral effect of interferon
-deals with viral replication (entering cell)
-warning neighbour cells that they are virally infected
50
NK cells
-naturally occurring lymphocyte like cells
-nonspecific
51
Mode of action of NK cells
Release chemicals to kill bodies own cells that are virally infected
52
Adaptive immune responses two types
Ab mediated and cell mediated
53
Antibody mediated
-production of B lymphocytes
54
The state of B cells that are able to produce antibodies
Plasma cells
55
Cell mediated immunity
Production of activated T lymphocytes
-directly attack unwanted cells
56
Peripheral lymphoid tissues
Mobile units that can go anywhere
-important: for readiness of immune response
57
Antigen
What the cell is responding Togo
-induce immune response
58
More complex a molecule is the greater its
Antigenicity
59
Each lymphocyte has surface receptors for binding with ____ particular type of possible antigen
One
60
How are lymphocytes super specific
Surface receptor only recognizes one type of antigen
61
Most B cells differentiate into
Active plasma cells
-antibody producing cells
62
Other B cells become
Dormant
-memory cells
-do not produce antibodies but help in future
63
Receptor sites on cell surface recognize
One specific antigen
64
Plasma cells
Produce antibodies
-enter blood
-only for one specific antigen
65
Plasma (activated B cell) cells have a greatly increased
Endoplasmic reticulum
-protein making machinery
66
When antibody combines with an antigen, what happens?
Marked for destruction
67
IgM
B cell surface receptor for antigen attachment
-early stages of response
68
IgG
Produced in large amounts when body is exposed to same antigen
-most abundant
69
IgM and IgG produce what?
Most specific response
70
Properties of tail portion of antibodies
Determines functional properties of antibody
71
Properties of tip of antibodies
Unique for each different antibody
-identical binding gradients
72
Agglutination
Clumping of antigenic cells
-can bind foreign cells
73
Neutralization
A way of preventing toxins from interacting with susceptible cells
-recognize and bind to toxin
-binding causes toxin to be unable to affect (mopping up)
74
Four ways antibodies can elimate invading microbes
-anggulation
-complement system
-phagocytosis (opsonization)
-NK
75
Antibodies acting as opsonization
Macrophage has antibodies that recognize antigen on invading cell and phagocytes cell
76
When are B lymphocytes produced
During fetal development
77
Clonal selection of B lymphocytes
All offspring of particular B lymphocytes form a family of identical cells or a clone
78
What does it mean by an antibody can only recognize one antigen
One type of cell
-there are different actual cells but same (clones)
79
Memory cells
When re exposed to same antigen, allows body to be ready for immediate action
-dormant
-small percentage
80
Primary vs secondary immune response
Primary- takes longer, is less of an antibody response
Secondary- quick response, very large onset of antibody response
81
Active immunity
Self generated
-results from exposure to an antigen
-natural or vaccine (deliberate) based
82
Passive immunity
Borrowed immunity
-from transfer of preformed antibodies
-immediate protection
Eg- mother passes antibodies from breast milk
83
T cells account for what percentage of total lymphocyte in circulation
50-70
84
T cells are important in defence against
Most viral infections
-regulatory role
85
What does it mean by T cells do not secrete antibodies?
T cells bind directly to targets
86
Killer T cells
Release chemicals that destroy targeted cells
87
Vaccines
Deliberate exposure to antigen to produce antibodies
-ensures that “first” exposure in real time acts as the primary exposure (faster and higher antibody count)
88
Do T cells produce antibodies
NOR
89
MHC proteins allow
For T cells to activate an attack, since if they are present on cell then T cells can respond
90
How quick is a T cell response
A few days
91
CD8 cells are called
Cytotoxic T cell
92
CD4 cells
Helper T cells
93
Cytotoxic T cells
Destroy host cells harbouring anything foreign
-cancer or viral
94
Helper T cells/ CD4
-coordinates immune system
-secrete chemicals to amplify activity
95
Examples (3) of chemicals helper cells can secrete
-B cell growth
-T cell growth
-macrophages migration inhibition factor
96
T cell growth factor is
Interleukin-2
97
Memory T lymphocytes
Same as memory B cells
98
MHC stands for
Major histocompatibility complex
99
T lymphocyte cell mediated immunity—> antigen must be
Complexed with another cellular protein
100
How does a T lymphocyte recognize abnormal cell
-finds MHC with abnormal protein (cell will advertise this abnormality)
-T cell identifies and kills cell
101
Organ transplant is related to
MHC molecules
102
T cells have antigen receptors which recognize
Antigens only when associated with MHC molecules
103
Antigen presentation
Cells is presenting and making the protein abnormality stand out to be destroyed by T cell
104
Two classes of MHC molecules
Class1 and Class 2
105
Class 1 vs Class 1 (MHC)
1- nucleated cells
2-macrophages, dendritic cells, activated B cells (immune system)
106
Cytotoxic T cells
Target host infected with virus
-bind to viral antigen
107
Killing method of cytotoxic T cells
May kill cell directly or thru enzymes (self destruction)
108
Once a killer cell binds to its target cell what takes place
Granules in killer cell reaches surface of killer cell
-granules contain perfroin and empty into space between killer cell and target cell
109
What happens to performing molecules when exposed to Ca
In the ECF space, the performing turns from a spherical to a cylindrical shape
110
What do the cylindrical shaped perforin molecules do
-Bind to the target cell membrane and insert into it
-grouping together like barrel shaped pores
111
How do the perforin pores on target cell lead to cell death
Allow entry of salt and water which causes cell to swell and burst
112
Cytotoxic T cells require (class one or two)
Class 1 MHC
-most cells
113
Are helper T cells killer cells
No
114
Helper T cells function
-secrete chemicals (cytokines)
-help all parts of immune system
115
Cytokines
Proteins that assist in messages between immune cells
116
CD4 cells require (class 1 or 2)
Class 2
-immune cells
117
Lymphocytes respond only to
Antigens presented to them by antigen presenting cells
118
What can be an antigen presenting cell
Macrophages
119
After phagocytosis occurs how does antigen presentation take place
-macrophage digests the microbe into antigenic peptides
-antigenic peptides bind to MHC
-presents antigen to cell surface
120
Antigen presenting macrophages secrete
Interleykin -1
121
Defence against viral invasion as free in ECF
-macrophages
-neutralization
-complement cascade
122
Defences against viral invasion: virus has entered the host cell
-interferon
-NK cells
-cytotoxic T cells
-helper T cells
123
What happens once a virus infected cell is destroyed
-free virus is released into ECF
-attacked directly by macrophages, antibodies and activated complement
