Innate Immunity (7.2) Flashcards
1
Q
State the 2 classifications of immune responses
A
- innate
2. adaptive
2
Q
State whether or not the innate immune response is classified as specific or non-specific
A
Non-specific
3
Q
State whether or not the adaptive immune response is classified as specific or non-specific
A
Specific
4
Q
Describe innate immunity
A
Non-specifically protects against a wide variety of pathogens
5
Q
State the 3 unique types of barriers offered by the innate immune response
A
- chemical
- physical
- microbiological
6
Q
Provide 1 example of a physical barrier
A
Skin/bark
7
Q
Provide 1 example of a chemical barrier
A
Lysozyme enzymes in salivia
8
Q
Provide 1 example of a microbiological barrier
A
Microflora
9
Q
Describe lysozyme enzymes
A
Antibacterial enzyme present in body secretion that disrupts the bacterial cell wall
10
Q
Describe microflora
A
Microorganisms that colonise particular sites
11
Q
Provide 4 examples of physical barriers of defence in plants
A
- thick cuticles on cell wall
- thick layer of bark
- closing of stomata
- vertical leaf orientation
12
Q
Provide 3 examples of physical barriers of defence in animals
A
- epithelial cells (keratinised skin)
- mucus-secreting membranes
- cilia
13
Q
Provide 3 examples of chemical barriers of defence in plants
A
- saponin (wheat)
- citronella (lemongrass)
- chitinases (barley, tomato, banana)
14
Q
Provide 5 examples of chemical barriers of defence in animals
A
- lysosome enzymes/toxic metabolites (tears, sweat, salivia)
- acidic secretions (vagina)
- stomach acid
- digestive enzymes
- proteins that act as surfactants (lungs)
15
Q
Describe stomata
A
Pore structure bordered by two guard cells found in plants
16
Q
Describe cuticle (in plants)
A
Protective film covering the epidermis of leaves
17
Q
Describe metabolites
A
Intermediate products of metabolic reactions catalyzed by enzymes within cells
18
Q
Describe surfactants
A
Substances that lower surface tension of certain fluids that are also antimicrobial
19
Q
Describe the role of vertical leaf position in innate immunity
A
Water is unable to collect on leaves and pathogens that rely on water for motility cannot invade plant cells
20
Q
Describe the role of mucus-secreting membranes in innate immunity
A
Trap invading organisms in mucus
21
Q
Describe the role of membranes lined with cilia in innate immunity
A
Sweep foreign bodies that line the airway away
22
Q
Describe the role of surfactants in innate immunity
A
Lower the surface tension of lung fluids and prevent alveoli collapse
23
Q
Provide a possible reason as to why pathogens can be more easily eliminated by macrophages as a result of surfactant presence
A
Surfactants coat the pathogens making it easier for macrophages to engulf them due to lower surface tension
24
Q
Describe macrophages
A
Large white blood cell that is responsible for engulfing and digesting foreign matter in the body
25
Provide an alternative term to describe non-pathogenic bacteria
Normal flora
26
State 6 possible locations of non-pathogenic bacteria in the human body
1. skin
2. mouth
3. nose
4. throat
5. lower part of the gastrointestinal tract
6. urogenital tract
27
State what the presence of normal flora prevents
Growth and colonisation of other bacteria
28
State what the effects of antibiotics can be on the presence of normal flora
Disrupt normal flora (as antibiotics does not discriminate against beneficial and harmful bacteria)
29
State what kind of defence and in what organism the cell wall is employed
Physical barrier in plants
30
State what kind of defence and in what organism bark is employed
Physical barrier in plants
31
State what kind of defence and in what organism the closing of stomata is employed
Physical barrier in plants
32
State what kind of defence and in what organism the positioning of leaves is employed
Physical barrier in plants
33
State what kind of defence and in what organism a physical barrier of epithelial cells is employed
Physical barrier in animals
34
State what kind of defence and in what organism a mucus-secreting membrane is employed
Physical barrier in animals
35
State what kind of defence and in what organism a membrane with cilia is employed
Physical barrier in animals
36
State what kind of defence and in what organism the use of lysosomal enzymes and toxic metabolites are employed
Chemical barrier in animals
37
State what kind of defence and in what organism stomach acid and digestive enzymes are employed
Chemical barrier in animals
38
State what kind of defence and in what organism surfactants are employed
Chemical barrier in animals
39
State what kind of defence and in what organism acidic secretion are employed
Chemical barrier in animals
40
State what kind of defence and in what organism non-pathogenic bacteria are employed
Microbiological barrier in animals
41
Describe the role of non-pathogenic bacteria in innate immunity
Normal flora produced chemicals that reduce pH of the micro environment and prevent pathogenic growth
42
State whether or not the innate immune response is found in all organisms
Yes.
43
State 5 characteristics of the innate immune response in vertebrates
1. non-specific
2. rapid
3. present in all animals
4. fixed responses
5. no immunological memory of infection-causing pathogen
44
Describe leukocytes
White blood cells
45
Describe white blood cells
Immune cells that are present in blood and other tissues
46
State the specific molecules found on the surface of white blood cells
Pattern recognition molecules
47
Provide a term to describe the 'pattern recognition molecules' on the surface of white blood cells
Toll-like receptors (TLRs)
48
State what TLRs can recognise
Different PAMPs
49
Describe PAMPs
Pathogen-associated molecular patterns
50
State whether or not PAMPs are microbial
Yes.
51
State whether or not all TLRs are capable of recognising all PAMPs
No. Different TLRs recognise different PAMPs.
52
Describe the specificity of PAMPs to pathogens
PAMPs are common to many pathogens
53
Explain the specificity of the innate immune response to PAMPs
Innate immune response is not specific as PAMPs are common to a range of pathogens
54
Describe phagocytes
Leukocytes capable of engulfing pathogens or foreign particles to destroy them
55
State whether or not phagocytes can be classified as leukocytes
Phagocytes are leukocytes
56
State 4 types of phagocytes
1. neutrophils
2. macrophages
3. monocytes
4. dendritic cells
57
State what TLRs on a phagocyte interact with
Microbe's PAMPs
58
State what phagocytic TLR and microbial PAMP interaction results in
Signal transduction
59
State what signal transduction stimulated by interactions between phagocytic TLR and microbial PAMP results in
Phagocytosis of microbe
60
Describe APCs
Cell that uses MHC-II on its surface to present foreign antigens to helper T lymphocytes to elicit adaptive immune responses
61
State what APC stands for
Antigen-presenting cell
62
Describe antigen
A substance that reacts with antibodies and T lymphocyte receptors
63
Describe helper T lymphocytes
Lymphocytes that bind to antigen-MHC II complexes on antigen-presenting cells and active B lymphocytes to secrete antibodies
64
State what occurs when APCs phagocytose a pathogen
Fragments of digested antigens are linked to MHC-I proteins and displayed on the membrane surface
65
State the 2 classes of MHC proteins
1. MHC-1 (class 1)
| 2. MHC-2 (class 2)
66
State the common location of MHC-I proteins
Nucleated cells
67
State what MHC-I proteins often present
Peptide antigens derived from the proteins of pathogens in the cytoplasm of non-phagocytic cells
68
State to what cells MHC-I proteins present peptide antigens to
Cytotoxic T lymphocytes
69
Describe cytotoxic T lymphocytes
T lymphocyte stimulated by cytokines that bind to antigen MHC-I complexes on infected host cells and release cytotoxic compounds destroying infected cells
70
Describe what the absence of MHC-I proteins allows
NK cells to identify and destroy non-self cell (included cells that have been infected/damaged)
71
Describe whether or not MHC-II proteins can be expressed on all cells
Conditionally
72
State the common location of MHC-II proteins
Surface of APCs
73
State what the presence of antigens on MHC-II proteins activates
Helper T lymphocytes
74
State the 6 stages of phagocytosis and antigen presentation in an APC
1. engulfment foreign material
2. lysosome and phagosome fusion
3. enzyme degrade foreign material
4. foreign material broken down
5. antigen fragments presented on APC via MHCII
6. leftover fragments exocytosis
75
Describe how APCs communicate with other immune cells
Presenting antigens or fragments of antigens on the cell surface
76
State 8 cells involved in the innate immune response
1. neutrophil
2. basophil
3. macrophage
4. moncyte
5. eosinophil
6. mast cell
7. dendritic cell
8. NK
77
Describe the primary function of a neutrophil
- phagocytosis
- release defensins
- release cytokines
78
Describe granulocyte
Leukocyte characterised by the presence of numerous staining granules in the cytoplasm
79
Describe the 2 major classifications of leukocytes
1. granulocytes
| 2. agranulocytes
80
Compare and contrast granulocytes and agranulocytes
Granulocytes have granules in their cytoplasm and agranulocytes do not (observed light microscopy)
81
Compare and contrast granulocytes and agranulocytes
Granulocytes have granules in their cytoplasm and agranulocytes do not (observed light microscopy)
82
Describe the role of defensin release in the innate immune response
Disrupts bacterial and fungal membranes
83
Describe the role of cytokine release in the innate immune response
Attract other immune cells and trigger inflammation
84
Describe the primary function of a basophil
- release histamine
85
Describe the role of histamine in the innate immune response
Contributes to inflammation and consequently, blood vessel dilation
86
Describe histamine
Organic compound involved in the inflammatory response
87
Describe the primary function of a macrophage
- phagocytosis
- antigen presentation
- cytokine release
88
Describe the primary function of a eosinophil
- antigen presentation
- release cytokines and cytotoxic chemicals
- phagocytosis (limited role)
89
Describe the primary function of a moncyte
- phagocytosis
90
Describe the primary function of a mast cell
- release histamine
91
Describe the primary function of a dendritic cell
- phagocytosis
| - antigen presentation
92
Describe the primary function of a NK cell
- recognise virus-infected/cancerous cells
- release cytotoxic chemicals
- release cytokines
93
Provide 4 examples of granulocytic leukocytes
1. neutrophil
2. basophil
3. eosinophil
4. mast cell
94
Describe mast cells
Immune cell containing granules of histamine
95
State 2 agents that are involved in both the adaptive and innate immune response
1. complement proteins
| 2. cytokines
96
Describe complement proteins
Proteins that are able to kill foreign cells by lysis
97
Describe cytokines
Small signalling molecules of the immune system that coordinate many aspects of the immune response
98
State the common location of complement proteins
Bodily fluid
99
State in what form complement proteins are often found within bodily fluids
Inactive form
100
State in what situation complement proteins are activated
Non-specific immune response to certain antigens and carbohydrates on the surfaces of some bacteria and parasites
101
State what the activation of complement proteins results in
Enzyme-triggered reaction that leads to lysis of invading pathogens
102
State whether or not complement proteins activated by antigen-antibody complexes are involved in the adaptive immune response
Yes
103
Provide a reason why cytokines may be released by body cells
Response to cell damage or pathogenic presence
104
State the 5 different types of cytokines
1. interferons
2. chemokines
3. interleukins
4. lymphokines
5. tumour necrosis factor
105
State the 5 different types of cytokines
1. interferons
2. chemokines
3. interleukins
4. lymphokines
5. TNF
106
Describe the specificity of interferons
Non-specific and can act against any virus
107
State whether or not some viruses can inhibit the production of interferons
Yes.
108
Describe chemokines
Class of cytokines that act as chemical attractants
109
State the role of chemokines
Attract leukocytes to sites of infection/inflammation
110
State the role of interferons
Activate infected cells to produce enzymes that break down viral RNA
111
State the role of interferons
Activate infected cells to produce enzymes that break down viral RNA
112
Describe interleukins
Class of cytokines that are released by cells in response to stimuli
113
Describe lymphokines
Class of cytokines that are released by T cells during the immune response to provide intercellular signals
114
State what TNF stands for
Tumor necrosis factor
115
Describe TNF
Class of cytokines that contributes to inflammation
116
Describe the manner in which interferons function
Autocrine
117
Describe autocrine
Substance secreted by a cell also has an effect on that cell
118
Describe inflammation
Accumulation of fluid, plasma proteins and leukocytes that occurs when tissue is damaged or infected
119
State 5 symptoms of inflammation
1. heat
2. pain
3. swelling
4. redness
5. loss of function
120
State between what cells/organisms the interaction that causes an inflammatory response occurs
Leukocytes and pathogens
121
State between what cells/organisms the interaction that causes an acute inflammatory response occurs
Phagocytes and pathogens
122
State the 3 major factors that trigger the inflammatory response
Production, activation or release of peptides and proteins
123
State whether or not inflammation can occur as part of the adaptive immune response
Yes.
124
Outline the details within each of the 3 major stages of inflammation
1. increased diameter/permeability of blood vessels due to histamine release
2. phagocyte migration and engulfment via phagocytosis
3. tissue repair
125
Describe the process of increased diameter and permeability of blood vessels on the inflammatory response
Histamine is released which increased vessel dilation and permeability
126
Describe the process of phagocyte migration and phagocytosis in the inflammatory response
Phagocytes squeeze between cells of blood vessel walls to reach the damaged area where they destroy invading microbes.
127
Describe the process of tissue repair in the inflammatory response
Functioning cells or supporting connective cells create new tissue to replace tissue that is dead/damaged.
128
Outline the effect of increased dilation and permeability of blood vessels in the inflammatory response
Allow leukocytes and fluid containing peptides and proteins to enter infected tissue
129
State what must occur before the inflammatory response ceases
Pathogen is eliminated and wound heals
130
State what cells are responsible for the release of histamine in the inflammatory response
Mast cells
131
State what injured cells release in the inflammatory response
Chemokines
132
State what structures release clotting factors at the site of an open wound
Platelets
133
Describe the role of platelets in the inflammatory response
Release clotting factors at the site of the wound
134
State what causes the production of pus in the inflammatory response
Congregation of neutrophils, phagocytosed pathogens and debris
135
Describe fever
Increase in body temperature that results when the temperature set point of the hypothalamus is set to a higher level by inflammatory cytokines
136
State what the normal body temperature in humans is classified as
37C
137
State when a fever occurs
When the body temperature is above normal
138
State what fever results in
Slowing of bacterial and viral replication by shifting body temperature away from optimal range
139
State what a moderate increase in temperature may increase
Activity and proliferation of leukocytes
140
Provide an alternative term for cytotoxic T cells
Killer T cells
141
State whether or not complement proteins can bind to specific antigens on the surface of a bacterium
No
142
State whether or not phagocytes can release histamine in response to a bacterial infection
No
143
State what the molecules on the surface of cells are that enable cytotoxic and NK cells to distinguish between self and non-self
Antigens
144
State whether or not dendritic cells present self-antigens to lymphocytes
No
145
State whether or not dendritic cells are involved in the inflammatory response
Yes
146
State what part of the body's defence system responds quickly to the entry of a foreign object
Non-specific or innate immune response
147
State why swelling at the site of entry of a foreign object occurs
Build up of fluid in the area. The foreign object would have caused damage to cells in the area and these cells would release histamine, causing capillaries to swell and become leaky
148
State how excess fluid in an affected area disappears
Fluid drains into lymph vessels and is returned to general circulation
149
State what increases the temperature of an infected area during an inflammatory response
Phagocytes would be active, producing heat as a result of collisions between lysosomal enzymes and fragments of the foreign particle
150
State what the redness surrounding an infection site is caused by
Histamine increases blood vessel dilation and vascular permeability to increase in redness
151
State the 3 major parts of antibodies
1. light chain
2. constant region
3. heavy chain
152
State what the function of the variable region on antibodies is
Variety in antigen-binding sites enables the immune system to respond to large numbers of pathogens.
153
State 2 roles of fever in the innate immune response
1. increase leukocyte activity
| 2. decrease optimal temperature of organism for viruses and bacteria - slowing replication
154
State the 3 major stages of the inflammatory response
1. Vascular stage
2. Cellular stage
3. Resolution stage
155
Describe interleukins
A class of glycoproteins synthesised by leukocytes which regulate immune responses
156
State whether or not red blood cells have MHCI markers
No
