Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Year 3 > Introduction to Immunology > Flashcards

Introduction to Immunology Flashcards

(152 cards)

Start Studying
1
Q

what are the physical barriers to infection?

A

skin and epithelial mucosa
Secretions
normal flora

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how does the resp/GI/GU systems prevent infection?

A

Antimicrobial peptides secreted by epithelial cells in resp/ GI/ GU tracts (also secreted by phagocytic cells) – have anti-bacterial properties – inc cecropins, magainins, defensins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how do secretions prevent infection?

A

o Sweat, tears, saliva, gastric acid, sebaceous glands, mucus, breast milk
o Saliva – lysozyme (digests proteoglycan in bacterial cell walls), IgA, IgG and lactoferrin
 IgA prevents attachment of microbes and may neutralise microbes insitu
 Lactoferrin sequesters free iron (used my microbes) and has direct antimicrobial effects – bind to lipopolysaccharide part of bacterial membrane, causes oxidative damage of the membrane, which results in cell lysis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how does normal flora prevent infection?

A

o Commensal bacteria – compete for nutrients, prevent attachment, release fatty acids, and antibacterial proteins, prevent invasion
o Lactobacilli in vagina – cause acidic pH (4.0-4.5)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the physiological defences agains infection?

A

o Temperature (fever), pH, location of immune cells within the bloodstream (can readily attack when and wherever microbes invade)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how do burns allow infection?

A

and dry mouth

allow access and more optimal growing conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how does cystic fibrosis lead to increased infection?

A

The increased viscosity of secretions in cystic fibrosis reduce the ability of the cilia to clear infections effectively, leading to repeated infections, and allows damage to the lungs to occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how does normal gut bacteria contribute to infection?

A

without normal gut flora keeping gut pathogens under control, other bacteria can increase in number and cause problems, such as a toxic megacolon here as a result of clostridium difficile infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

name the molecules of the innate immune system

A

complement
interferon
cytokines
acute phase reactants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

name the receptors of the innate immune system

A

pattern recognition receptors: toll-like receptors, mannan binding like lectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

name the molecules of the adaptive immune system

A

immunoglobulins

cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

name the receptors of the adaptive immune system

A

TCR - t cell receptor
BCR - b cell receptor
MHC/HLA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

discuss the innate immune system

A 
•	First line of defence
•	Rapid
•	Already present at birth
•	Some specificity
•	No memory – same response with re-exposure
•	Detects alteration from haemostasis
o	Damage recognition – host
o	Pathogen recognition – pathogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

name the 5 activators of inflammation in the innate system

A 
damage to tissues e.g. burns
microbial infection
complement activation
autoimmunity
allergens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

name the mechanism involved in inflammation in the innate immune system: damage to tissues

A

prostaglandin

leukotriene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

name the mechanism involved in inflammation in the innate immune system: microbial infection

A

exotoxins, endotoxins
TLRs - macrophages, mase cells
IL-1, IL-6, IL-12, TNF-a
NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

name the mechanism involved in inflammation in the innate immune system: complement activation

A

C3a

C5a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

name the mechanism involved in inflammation in the innate immune system: autoimmunity

A

immune complexes
complement
T-cel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

name the mechanism involved in inflammation in the innate immune system: allergens

A

mast cell degranulation

histamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

name the stages in the innate immune system

A 
inflammation
recruitment of immune cells
activation of complement 
opsonisation
phagocytosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what happens as a result of inflammation in the innate immune response?

A 
vasodilation
loosening of endothelial tight junctions
increased cell adhesion molecules
chemotaxis
smooth muscle contraction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

with a diagram describe the recruitment of immune cells in the innate response

A

see notes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

draw a series of diagrams to show the activation of complement in the innate response

A

see notes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is opsonisation?

A

to prepare for eating

reduced repellent negative charge of cell membrane to allow phagocyte to come closer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
give examples of opsonins
complement antibodies plasma proteins
26
use a diagram to describe phagocytosis
1. phagocyte moves towards microbe 2. phagocyte attaches to microbe via opsonin 3. endocytosis of microbe within phagosome 4. phagosome fuses with lysosome 5. oxygen dependent species result in microbe death 6. release of microbe products
27
what is the life span of neutrophils?
few days
28
what are the main functions of neutrophills?
phagocytosis | degranulation
29
what are the degranulation products in neutrophils?
peroxidase defensins acid and alkaline phsophatases
30
what are the main tagetts of neutrophils?
bacteria | fungi
31
name the receptors found on neutrophils
``` o Toll like receptors o Complement o IgG o Chemokine IL-8 o Chemoattractant C5a o ICAM + VCAM – adhesion to endothelium ```
32
life span of eosinophils
8-12 days
33
function of eosinophils
extracellular killing via degranulation
34
what are the components of eosinophil degranulation?
peroxidase major basic protein IL-8, cytokine
35
what induces degranulation of mast cels and basophils?
major basic protein
36
main target for eosinophils
parasites
37
what do IL-5 and IL-3 stimulate?
production and release of eosinophils from BM | expression of IgE receptors on eosinophils
38
life span of basophils
few days
39
where are basophils predominately found?
within circulation
40
main fuction of basophil
degranulation
41
degranulation products of basophils
histamine prostaglandins and leukotrienes cytokines: IL-4, IL-3
42
main target of basophils
parasites
43
receptors found on basophils
o Surface bound IgE o C3a, C5a anaphylatoxins o Toll-like receptors
44
draw: neutrophil
see notes
45
draw: eosinophil
see notes
46
draw: basophil
see notes
47
draw: mast cell
see notes
48
draw: macrophage
see notes
49
life span of mast cells
long
50
where are mast cells found?
present in tissues exposed o external environment e/g/ skin, lung, gut
51
what is the function of mast cells?
degranulation through cross linking of IgE receptors
52
degranulation products of mast cells
``` o Histamine o Proteases o Reactive oxygen species o Cytokines – TNF alpha, IL-4, IL-3 o Leukotrienes and prostaglandins ```
53
main targets for mast cells
parasites
54
receptors found on mast cells
``` o Surface bound IgE o C3a and C5a o Damage associated molecular patterns o Toll like receptors o Complement o Others: that can bind drugs e.g. opioids and antibiotics ```
55
what are macrophages? give examples of where they are found
``` • Tissue-based monocytes o Kupffer (liver), microglial (brain), mesangial (kidney) ```
56
life span of macrophages
months to years
57
main functions of macrophages
phagocytosis antigen presentation to T cells release TNF-a, IL-2, IL=6
58
receptors found on macrophages
o Toll like receptors o Fc for IgG and IgA o C3b o MHC class I and II
59
draw: dendtiric cell
see notes
60
draw: NK cell
see notes
61
where are dendritic cells found?
tissues exposed to external environment
62
once activated where do dendritic cells migrate to? how?
lymphoid tissues | binding to microbes via pattern recognition receptors
63
main functions of dendritic cells
o Phagocytosis o Antigen presentation to CD4+ T cells via MHC II  Shape enhances activation o Secrete TNF alpha, IL-12, IL-23
64
discuss follicular dendritic cells
o Mesenchymal origin o Within follicles of lymphoid tissue o Do not express MHC II but interact with B cells
65
what are NK cells activated by?
IFN and macrophage derived cytokines e.g. IL-2
66
main functions of NK cells
o Bind to and kill virus-infected and cancerous cells –reduced MHC I expression o Release of perforin + granzymes from granules  Perforates cell, inserts proteolytic enzymes, induces apoptosis o Also induce apoptosis by binding to FasL molecules on virus o Release IFN gamma and TNF alpha
67
what are NK cells inhibited by?
normal self signal via MHC I
68
receptors found on NK cells
``` o Killer activation receptors o Killer inhibitory receptors – recognise MHC class I o Toll-like receptors o Fc receptors o Adhesion molecules o FasL ```
69
name the common cytokines
IL-1, 2, 4, 5, 6, 8, 12
70
what produces IL-1
macrophages and epithelial cells
71
what produces IL-2
t cells
72
what produces IL-4
Th2 cells | mast cells
73
what produces IL-5
Th2 cells | mast cells
74
what produces IL-6
t cells | macrophages
75
what produces IL-8
macrophages monocytes keratinocytes fibroblasts
76
what produces IL-12
b cells | macrophages
77
function of IL-1
``` fever lymphocyte activation acute phase proteins mobilisation of PMNs activates endothelium ```
78
function of IL-2
induces proliferation of T and NK cells
79
function of IL-4
induces B cell activation adn Th2 IgE production | inhibits Th1 response
80
function of IL-5
induces eosinophil growth and differentiation | B cell activation and IgA response
81
function of IL-6
lymphocte activation, fever, acute phase proteins
82
function of IL-8
chemotaxis of PMNs
83
function of IL-12
induces Th1 and activates NK cells | inhibits Th2 response
84
what produces TNF-alpha?
macrophages | T cells
85
what produces IFN-gamma
Th1 cells | NK cells
86
what produces prostaglandins and leukotrienes?
chemoattract t cells eosinophils mast cells basophils
87
what produces nitric oxide
macrophages | PMNs
88
functions of TNF-a
increases vascular permeability | induces fever
89
functions of IFN-gamma
activated macrophages and PMNs Induces Th1 Inhibits Th2
90
functions of histamine
increases vascular permeability | smooth muscle contraction
91
functions of prostaglandins and leukotrienes
increase vascular permeability smooth muscle contraction stimulate mucus secretion
92
functions of nitric oxide
vasodilation | smooth muscle relaxation
93
name 2 pattern recognition receptors
toll-like receptors | mannose receptor
94
what expresses toll-like receptors?
dendritic cells macrophages epithelial cells
95
function of toll-like receptors
bind lipopeptides, dsDNA, flagellin
96
what expresses mannose receptors
macrophages epithelial cells dendritic cells
97
function of mannose receptor
binds mannose-like carbohydrates (PAMPs) on bacteria, viruses, fungi
98
function of b-cell receptors
membrane bound immunoglobulin | recognise antigen directly
99
function of t-cell receptor
antigen needs to be processed and presented via MHC I or II before recognition by T cell
100
CRP is produced in the liver is response to what?
IL-1 IL-6 TNF
101
function of CRP
binds to bacteria | acts as an opsonin for phagocytosis
102
describe the adaptive immune response
* Specificity and memory * Delayed response – days to weeks * B-cell – antibody mediated * T-cell * Mucosa associated lymphoid tissues
103
what cells are found in the spleen?
lymphoid follicles - b-cells, follicular dendritic cells macrophages plasma cells
104
function of the spleen
filters blood | traps microbes and immune complexes
105
give 3 examples of mucosa associated lymphoid tissue
GALT BALT - bronchus NALT
106
what is GALT?
o Waldeyer’s ring o Peyers patches in small intestine o Appendix o Lymphoid follicles in large intestine and rectum
107
describe b cell maturation and differentiation
see notes
108
draw an IgG, IgE, IgD molecule
y shaped
109
draw an IgM molecule
round
110
draw an IgA molecule
linear
111
when is IgM first produced?
as a foetus
112
when is IgG first produced?
birth
113
when is IgA first produced?
1-2 months after birth
114
what are the functions of antibodies?
free antigen neutralisation opsonisation for phagocytosis activation of complement antigen presentation
115
where are antibodies usually cleared from circulation?
liver | spleen
116
another name for major histocompatibility complex
human leucocyte antigens
117
what is the function of MHC?
presentation of antigens to T cells
118
where are MHC I found?
all nucleated cells
119
what does MHC I bind to?
CD8+ T cells
120
where are MHCII found?
antigen presenting cells: dendritic cells, macrophages, B cells
121
what does MHC II bind to?
CD4+ T cells
122
using a diagram show the pathways of antigen processing for MHC
see notes
123
name the CD4+ T cells
Th1 Th2 Th17 T regs
124
draw a diagram to show T cell maturation
see notes
125
function of Th1 CD4+
protection against intracellular pathogens | autoimmunity
126
function of Th2 CD4+
protection against extracellular pathogens | allergy, asthma
127
function of Th17 CD4+
protection against extracellular pathogens | autoimmunity
128
with the help of a diagram show b cell activation by T helper cells
see notes
129
what does class switching between IgM and IgM require?
stimulaiton of the B cell by a t helper cell
130
with the help of a diagram show CD8+ T cell perforin induced apoptosis
see notes
131
describe Fas-Mediated apoptosis of CD8+ T cells
* Nucleated cells infected with some viruses upregulate fas expression (CD95) * When fas antigens present with MHC I molecules to CD8+, this causes the CD8+ cell to express a fasL receptor on their cell membrane * Binding of fas with fasL causes target cell apoptosis
132
name the intracellular pathogens invoking an immune response
mycobacterium viruses protozoa
133
name the surface pathogens invoking an immune response
helminths | arthropods
134
name the extracellular pathogens invoking an immune response
bacteria | fungi
135
name the innate molecules involved in the immune response in intracellular pathogens
IFN macrophages NK cells dendritic cells
136
name the innate molecules involved in the immune response in surface pathogens
mast cells | eosinophils
137
name the innate molecules involved in the immune response in extracellular pathogens
neutrophils
138
name the adaptive molecules involved in the immune response in intracellular pathogens
Th1, CD4+ cytotoxic CD8+ IgM, IgG, IgA
139
name the adaptive molecules involved in the immune response in surface pathogens
Th2, CD4+ | IgE
140
name the adaptive molecules involved in the immune response in extracellular pathogens
Th17, CD4+
141
describe how immune function varies in the elderly
 Thymic involution  Fewer naïve T cells – dependent on memory T cells  Reduced ability for T cell expansion  Reduced B cell development and diversity • Diminished response to vaccination  More dependent on innate immunity • But reduced function of pattern recognition receptors and superoxide killing
142
how can gender affect immune function?
oestrogen vs progesterone and testosterone
143
what may cause immune deficiency?
genetic cause other diseases drugs environment/iatrogenic insults
144
secondary causes of immune deficiency: environmental
malnutrition trauma burns
145
secondary causes of immune deficiency: disease
``` infection HIV diabetes renal failure asplenia malignancy - CLL, myeloma, lymphoma ```
146
secondary causes of immune deficiency: drugs
immunosuppressive antirheumatic antiepileptic
147
how does malnutrition cause immune deficiency? protein-calorie mal
immune defences require energy | proteins: cytokines, acute phase proteins, chemokines etc
148
how does malnutrition cause immune deficiency? zinc
essential for proliferating cells | deficiency: PMN, NK, monocyte, B and T cell impaired function
149
how does malnutrition cause immune deficiency? iron
enzymes within cellular function and metabolic pathways | deficiency = impaired innate immune function - toxic oxygen species
150
how do glucocorticoids cause immune deficiency?
o Anti-inflammatory –  Activate lipocortins: reduce phospholipase A2 and arachidonic acid release  Alter transcription of enzymes needed for inflammation
151
how does ciclosporin cause immune deficiency?
o Calcineurin inhibitor | o Reduced inflammatory cytokine release from T cells
152
how does rituximab cause immune deficiency?
o Binds to CD20 (B lymphocytes) | o Allows NK and complement mediated apoptosis

Year 3 (164 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions