Immunology Flashcards
1
Q
Which type of immunity is being described?
- first line of defence against pathogens
- recognition of traits shared by broad ranges of pathogens, using a small set of receptors
- rapid response
- can activate acquired immune system and inflammatory response
- ability to differentiate between host and pathogen
A
innate immunity
2
Q
Which type of immunity is being described?
- mounts specific and targeted response
- creation of immunological memory
- basis of vaccination
A
acquired immune system
3
Q
What are the 5 functions of the innate immune system?
A
- physical and chemical barriers
- complement activation
- activation of adaptive system
- phagocytosis
- immune cell recruitment
4
Q
Which physical barrier of the innate immune system is being described?
- physical barrier between body and outside world
- tight junctions in epithelium stop entry between cells
- desquamation (skin replacing itself) removes adhered pathogens
A
skin
5
Q
Which physical barrier of the innate immune system is being described?
- present in respiratory and GI tracts
- slimy surface stops adherence
- ciliated cells
- defensins (antimicrobial peptides)
A
mucous membranes
6
Q
Which chemical barrier of the innate immune system is being described?
- stomach acid
- digestive enzymes
- tears (lysozyme)
- mucous
- sweat
- pierce holes in bacterial cell walls
A
secretions
7
Q
Which type of mucous membrane is being described?
- contained in mucous of mucous membranes of all animal and plant cells
- abundant in neutrophils > kill phagocytosed pathogens
- broad spectrum of antimicrobial activity against gram-negative and gram-positive bacteria, fungi, parasites, and even enveloped viruses
- difficult for the microbes to acquire resistance to the defensins
A
defensins (antimicrobial protein)
8
Q
What does PAMPS mean?
A
pathogen associated molecule patterns
9
Q
What is being described?
- activate innate immune responses, protecting the host from infection, by identifying some conserved non-self molecules
A
PAMPS (pathogen associated molecule patterns)
10
Q
What is being described?
- proteins capable of recognising molecules frequently found in pathogens (PAMPs)
- soluble receptors in cytoplasm (NLRs and RLRs)
- membrane-bound receptors on host cell surface (TLRs) and (CLRs)
A
PRRs (pattern recognition receptors)
11
Q
What do toll-like receptors 1, 2, 4 and 6 recognise?
A
bacterial lipids
12
Q
What do toll-like receptors 3, 7 and 8 recognise?
A
viral RNA
13
Q
What does toll-like receptor 9 recognise?
A
bacterial DNA
14
Q
What do toll-like receptors 5 and 10 recognise?
A
bacterial or parasite proteins
15
Q
What is the name of the system being described?
- formed by the innate immune system
- inactive until triggered by an infection
- consists of 20 interacting soluble proteins in blood and extracellular fluid
A
complement system
16
Q
What can the complement system initiate?
A
- phagocytosis
- inflammation
- cell lysis
17
Q
What are the 3 pathways of the complement system?
A
classical pathway
lectin pathway
alternative pathway
18
Q
Which pathway of the complement system is triggered by Ag-Ab (antigen-antibody) complex?
A
classical pathway
19
Q
Which pathway of the complement system is triggered by microbial carbohydrates?
A
lectin pathway
20
Q
Which pathway of the complement system is triggered by activating surfaces?
A
alternative pathway
21
Q
What are the 8 cellular components of innate immunity?
A
- neutrophils
- monocytes
- eosinophils
- macrophages
- basophils
- dendritic cells
- mast cells
- natural killer (NK)
22
Q
All of the cellular components apart from the natural killer cell of the innate immune system are produced by which cell?
A
common myeloid progenitor cell
23
Q
What cell is the natural killer cell produced by?
A
common lymphoid progenitor cell
24
Q
Which cell type gives rise to lymphocytes?
A
lymphoid progenitor cell
25
Which type of receptor of natural killer cells do the following?
- recognise molecules that are expressed on the surface of cancer cells and infected cells, and 'switch on' the natural killer cell
activating receptors
26
Which type of receptor of natural killer cells do the following?
- on the surface of the natural killer cell recognise cognate MHC 1 (found on normal healthy cells), and this 'switches off' the natural killer cell, preventing it from killing
inhibitory receptors
27
What do cancer cells and infected cells often lose thus leaving them vulnerable to NK cell killing?
MHC 1
28
What are the 4 stages of natural killer cell killing mechanism?
1. natural killer cell releases cytotoxic granules containing perforin and granzymes
2. perforin creates pore in cell membrane
3. granzymes enter cell cytoplasm
4. granzymes induce apoptosis
29
What are the 3 phagocytic cells of the innate immune system?
- macrophages
- neutrophils
- mature dendritic cells
30
What is the 1st, 2nd and 3rd line of defence in the immune system?
1st - innate immunity
2nd - internal defences of the innate immune system
3rd - acquired immunity
31
Which type of immunity is being described?
- 3rd line of defence
- recognition of traits specific to particular pathogens, using a vast array of receptors
- slower response
acquired immunity
32
What are the 4 components of the 2nd line of defence in the innate immune system?
- phagocytic cells (neutrophils and macrophages)
- antimicrobial proteins
- inflammatory response
- natural killer cells
33
What are the 3 components of the 1st line of defence of the innate immune system?
- skin
- mucous membranes
- secretions
34
What are the 2 types of acquired immunity?
- humoral response
| - cell-mediated response
35
What are 4 forms of inflammation in the oral cavity?
- glossitis
- oral mucositis
- pulpitis
- gingivitis and periodontitis
36
Which type of immune response of acquired immunity is being described?
- antibodies defend against infection in body fluids
humoral response
37
What 2 chemicals do natural killer cells release when they are activated that are involved in killing cells infected by pathogens?
perforin & granzymes
38
What is being described?
| - activate innate immune responses, protecting the host from infection, by identifying some conserved non-self molecules
PAMPs
39
Which type of immune response of acquired immunity is being described?
- cytotoxic lymphocytes defend against infection in body cells
cell-mediated response
40
Which type of immunity is being described?
- if innate immune system cannot eliminate a pathogen, this type of immunity is activated
- recognises presence of pathogen more efficiently than innate immune system
- immunity that an organism develops during lifetime (long-term protection)
- develops after exposure to antigens
acquired immunity
41
Which type of immunity is non-specific?
innate immunity
42
Which type of immunity is specific?
acquired immunity
43
What process and components of this process is being described?
the two systems work together to eliminate a foreign invader
phagocytic cells: crucial to non-specific immunity, are intimately involved in activating specific immunity
soluble factors: produced by specific immunity can increase the activity of these phagocytic cells
collaboration between innate and acquired immunity
44
What are the 4 characteristics of the acquired immune system?
1. discrimination between self and non-self
2. specificity
3. memory
4. diversity
45
Which characteristic of acquired immunity is being described?
- usually responds selectively to non-self, producing specific responses against the stimulus
discrimination between self and non-self
46
Which characteristic of acquired immunity is being described?
- can be directed against one specific pathogen or foreign substance among trillions
specificity
47
Which characteristic of acquired immunity is being described?
- response to a second exposure to a pathogen is so fast that there is no noticeable pathogenesis
memory
48
Which characteristic of acquired immunity is being described?
- generates enormous diversity of molecules
- T lymphocytes and B lymphocytes
- antigen-presenting cells (APC)
diversity
49
What are the 2 types of acquired immunity?
- antibody mediated immunity (AMI)
| - cell mediated immunity (CMI)
50
Which type of acquired immunity is being described?
- humoral immunity
- B lymphocytes/cells
antibody mediated immunity
51
Which type of acquired immunity is being described?
- cellular immunity
- T lymphocytes/cells
cell mediated immunity
52
Where in the body are B and T cells found?
blood, lymph, lymphoid tissues (eg. spleen, lymph nodes)
53
Which type of acquired immunity is being described?
the process of adaptive immunity manifested by the production of antibodies by B lymphocytes. It develops in bone marrow. B cells may be triggered to proliferate into plasma cells. Plasma cells produce antibodies.
humoral immunity (antibody mediated immunity)
54
Which type of acquired immunity is being described?
a protective immune process that involves the activation of phagocytes, antigen-sensitized cytotoxic T cells and the release of cytokines and chemokines in response to antigen.
cellular immunity (cell mediated immunity)
55
Which types of lymphocytes are being described?
- leave the bone marrow and continue to mature in the thymus
- mature T cells express antigen binding T-cell receptor (TCR)
T cells
56
Which types of lymphocytes are being described?
- mature in the bone marrow
- mature B cells express a unique antigen-binding B cell receptor (BCR)
B cells
57
Which types of lymphocytes are being described?
- substance that is capable of stimulating an immune response
- foreign antigens (pathogens, chemicals, toxins and pollens etc)
- self antigens (normal cellular proteins, autoimmune disease)
antigens
58
What are the 4 types of T cells involved in the cell-mediated immune response?
- helper T cells
- cytotoxic T cells
- memory T cells
- regulatory T cells
59
Which type of T cell associated with the cell-mediated immune response is being described?
- express CD4 - help with the activation, B cells and other immune cells
- binds to MHCII
helper T cells
60
Which type of T cell associated with the cell-mediated immune response is being described?
- express CD8 - responsible for killing infected host cells and cancer cells
- binds to MHCI
cytotoxic T cells
61
Which type of T cell associated with the cell-mediated immune response is being described?
- are antigen specific and remain long term after an infection is eliminated, allow rapid response upon re-exposure to infection
memory T cells
62
Which type of T cell associated with the cell-mediated immune response is being described?
- help distinguish between self and non self antigens, reducing risk of autoimmune diseases
- express CD4 and CD25
regulatory T cells
63
Which type of MHC complex is being described?
| - expressed by nearly all nucleated cells
MHCI
64
Which type of MHC complex is being described?
- expressed on certain immune cells, antigen presenting cells
- dendritic cells, macrophages, B cells
MHCII
65
What are the names of the 2 types of antigen?
exogenous and endogenous
66
Which type of antigen processing and presentation process is being described?
- eg. bacteria
- enters the endocytic processing pathway, within an acidic environment
- the antigen is degraded into small peptides
- peptides are presented with class II MHC molecules on the membrane of the antigen presenting cell
exogenous antigen
67
Which type of antigen processing and presentation process is being described?
- eg. virus infected cell, protein of cancerous cell
- which is produced within the cell itself is degraded within the cytoplasm into peptides
- which move into the endoplasmic reticulum, where they bind to class I MHC molecules
- the peptide - class I MHC complexes then move through the golgi complex to the cell surface
endogenous antigen
68
Basic antibody structure has 4 polypeptide chains, what are these?
- 2 identical light chains
| - 2 identical heavy chains
69
What are the 5 classes of immunoglobulins? (GAMED)
```
IgM
IgG
IgA
IgD
IgE
```
70
Which class of immunoglobulins is being described?
- first response to antigen
- can't cross placenta
- can be attached to B cells or free in blood plasma
- largest antibody
IgM
71
Which class of immunoglobulins is being described?
- always attached to B cell
- activates B cells
- can't cross placenta
IgD
72
Which class of immunoglobulins is being described?
- most common form
- crosses placenta (passive immunity to fetus)
- 75-85% of all antibodies in blood
- most abundant in blood plasma, can cross placental barrier so IgG is passive immunity to fetis
IgG
73
Which class of immunoglobulins is being described?
- secretions such as saliva, tears, intestinal juice, milk
- secretory because bathes body surfaces/important first defence
- secreted from mucous membranes
- in colostrum
IgA
74
Which class of immunoglobulins is being described?
- mucosal lining of respiratory and GI tracts/tonsils
- troublemaker antibodies involved in allergies
- histamine reactions and allergies (mast cells, basophils)
IgE
75
What are the 5 roles of antibodies? (NAOCE)
1. neutralisation
2. agglutination
3. opsonisation
4. complement activation
5. enhanced NK cell activity
76
Which role of antibodies is being described?
| - antibodies block the activity of a pathogen
neutralisation
77
Which role of antibodies is being described?
| - multiple pathogens are aggregated by antibody molecules
agglutination
78
Which role of antibodies is being described?
| - pathogens bound by antibodies are more efficiently engulfed by phagocytes
opsonisation
79
Which role of antibodies is being described?
| - antibodies bound to pathogens activate the complement cascade, resulting in lysis of the cell
complement activation
80
Which role of antibodies is being described?
| - abnormal body cells that are bound by antibodies are recognised by NK cells and are subsequently lysed
enhanced NK cell activity
81
What are the names of the 2 types of immunity?
active immunity and passive immunity
82
Which type of acquired immunity is being described?
- the form of immunity that is induced by exposure to a foreign antigen because the immunised individual plays an active role in responding to the antigen
active immunity
83
Which type of acquired immunity is being described?
- immunity can also be conferred on an individual by transferring antibodies from an immunised individual into an individual who has not encountered the antigen
- the recipient becomes immune to the particular antigen without ever having been exposed to or having responded to that antigen.
passive immunity
84
Which type of immunity is being described?
- antigens are introduced through natural exposure
- eg. infection, fighting off a cold
natural active immunity
85
Which type of immunity is being described?
- antigens are deliberately introduced in a vaccine
- eg. immunisation, polio vaccine
artificial active immunity
86
Which type of immunity is being described?
| - antibodies from the mother are transferred to her child across the placenta or in breastmilk
natural passive immunity
87
Which type of immunity is being described?
- antibodies produced by another person or an animal are injected
- eg. antibody transfer, rabies immunoglobin
artificial passive immunity
88
What are the primary lymphoid tissues?
bone marrow and thymus
89
What is the term used for secondary lymphoid tissues?
MALT (mucosa-associated lymphoid tissue)
90
What are 4 examples of secondary lymphoid tissues?
1. GALT (gut-associated lymphoid tissue) eg. Peyers patches, mesenteric lymph nodes, appendix, solitary lymph nodes
2. NALT (nasopharyngeal-associated lymphoid tissue) eg. salivary glands, tonsils
3. BALT (bronchus-associated lymphoid tissue)
4. Urogenital mucosa
91
The mucosal immune system consists of 2 functionally distinct types of tissue, these are?
- inductive sites
| - effector sites
92
Which type of tissue site in the mucosal immune system is being described?
- where naive B and T cells are clonal selected and expanded upon antigen contact
inductive sites
93
Which type of tissue site in the mucosal immune system is being described?
- where activated B and T cells relocate after antigen-priming inductive sites to express their effector functions
effector sites
94
What are the 2 components of mucosal immunity?
innate and adaptive
95
Which component of mucosal immunity is being described?
- mucosal barriers
- proteolytic enzymes
- antimicrobial molecules
- intestinal commensals
- immune cells
innate immune response
96
Which component of mucosal immunity is being described?
- unique epithelium for antigen uptake
- unique lymphocyte repertoire
- IgA dominated humoral response
- a need to minimise injury to the mucosal tissue whilst providing protection
adaptive immune response
97
What is being described associated with the innate immune response of mucosal immunity?
- goblet cells produce mucous to create a thick barrier that covers the GI epithelium and prevents easy access
- pathogens become trapped in the mucous and are expelled via peristalsis
- mucous also acts as a reservoir for secretory IgA
glycocalyx
98
What is being described associated with the innate immune response of mucosal immunity?
- prevent the passages of macromolecules
epithelial cell tight junctions
99
Which component of the innate immune response of mucosal immunity is being described?
- in the stomach (pepsin) and small bowel (trypsin, chymotrypsin, pancreatic proteases)
- break down large polypeptides into dipeptides and tripeptides
- peptides < 8-10 aa are poor immunogens
- enzymes cytotoxic to pathogens
proteolytic enzymes
100
What are the 3 antimicrobial molecules associated with the innate immune response of mucosal immunity?
lactoferrin
lysozyme
defensins
101
Which antimicrobial molecule associated with innate immune response of mucosal immunity is being described?
- binds iron and inhibits bacterial growth
lactoferrin
102
Which antimicrobial molecule associated with innate immune response of mucosal immunity is being described?
- cleaves cell wall of gram positive bacteria
lysozyme
103
Which antimicrobial molecule associated with innate immune response of mucosal immunity is being described?
- 30-40 aa peptides that disrupts the cell membranes of bacteria and fungi causing lysis
defensins
104
What component of the innate immune response associated with mucosal immunity is being described?
- provide enzymatic breakdown of food
- competes with pathogenic bacteria for space and nutrients
- prevents colonisation of the gut by more pathogenic species
- antibiotics disrupt homeostasis
intestinal commensals
105
What are 4 beneficial effects of indigenous GI microflora?
- increased IgA production by intestinal B cells
- bacterial antagonism
- convert dietary pre-carcinogens and carcinogens to non carcinogens
- synthesis of vitamin K and vitamin B complexes
106
What is being described associated with the adaptive immune response of mucosal immunity?
- M-cells microfilm cells
- M cells lack microvilli
- no glycocalyx coating
- designed to interact directly with antigens in the gut - portal of entry into GALT
- some pathogens gain entry via M cells (salmonella, shigella)
- M cells have irregular and ruffled apical (luminal) surface compared to neighbouring enterocytes
- M cells continuously sample antigens in the gut lumen
unique epithelium for antigen uptake
107
What process of acquired immunity is being described?
- M cells take up antigen by endocytosis and phagocytosis
- antigen is transported across the M cells in vesicles and released at the basal surface
- antigen is bound by dendritic cells, which activate T cells
uptake of antigens by M cells
108
What is being described associated with the adaptive immune response of mucosal immunity?
- an array of different immune cell types in lamina propria
unique lymphocyte repertoire
109
What is being described associated with the adaptive immune response of mucosal immunity?
intra-epithelial lymphocytes;
strategically located to respond to antigenic stimulation
- most T cells are CD8+
- limited repertoire of TCR - marked difference compared to peripheral T cells
- recognise a limited number of antigens
- prevents indiscriminate inflammation
- recognition of self stress antigens (MIC-A, MIC-B)
- T cells induce apoptosis of injured epithelial cells
unique lymphocyte repertoire
110
What is being described associated with the adaptive immune response of mucosal immunity?
lamina propria lymphocytes;
- T cells are predominantly CD4+
- limited capacity to proliferate
- weak proliferative responses to mitogens or specific antigens
- still act as helpers for B cells
unique lymphocyte repertoire
111
What is being described associated with the adaptive immune response of mucosal immunity?
lamina propria dendritic cells;
- found in cryptopatches, isolated lymph follicles, Peyers patches, and mesenteric lymph nodes
- subsets - seem to depend on chemokine signalling
- can protect colonic epithelial integrity by secreting interleukin-22
unique lymphocyte repertoire
112
What is being described associated with the adaptive immune response of mucosal immunity?
features of mucosal B lymphocytes;
- during their resting stages B cells can traffic through mucosal lymphoid follicles
- as plasmablasts they can migrate to the lamina propria
- they tend to become committed to IgA production
- however IgM and IgG are also produced
- there is some evidence that mucosal epithelial cells can condition mucosal DCs to present ag directly to mucosal B cells to produce immunogloblins
IgA dominated humoral response
113
What is being described associated with the adaptive immune response of mucosal immunity?
- IgA has multiple properties that are adapted for host defence in the GI tract
- IgA relatively resistant to proteolysis
- poor activator of complement
- inhibits; bacterial adhesion, macromolecule absorption, inflammatory effects of other immunoglobulins
- neutralises viruses, toxins
- enhances nonspecific defence mechanisms
- mediates antibody dependent cytotoxicity
IgA dominated humoral response
114
What is being described associated with the adaptive immune response of mucosal immunity?
gut anti-inflammatory mechanisms; secretory IgA
- IgA is unable to activate complement by classical or alternative pathways
- S-IgA can inhibit phagocytosis and chemotaxis of neutrophils and macrophages
- can down regulate synthesis of TNF-a (alpha) and interleukin-6
a need to minimise injury to the mucosal tissue while providing protection
115
What is the following the definition of?
- disease involving the breakdown of mechanisms responsible for self tolerance and induction of specific adaptive immune response against components of self
autoimmunity
116
What is the following the definition of?
| - any antigen that stimulates autoantibodies in the organism that produced it
autoantigen
117
What is the following the definition of?
| - antibody formed in response to an agent produced by the organism itself
autoantibody
118
What are the 2 types of self tolerance in autoimmunity?
central tolerance
and
peripheral tolerance
119
Which type of self tolerance of autoimmunity is being described?
- discriminate self from non self
- deletion of auto reactive lymphocytes during maturation in thymus & bone marrow
- induction of apoptosis
- weakly auto reactive B cells do not respond to receptor stimulation
- weakly self-recognising T cells differentiate into natural regulatory T cells (nTreg cells)
central tolerance
120
Which type of self tolerance in autoimmunity is being described?
- prevent over-reactivity
- develops after mature lymphocytes enter the peripheral tissues & lymph nodes
- Treg cells suppress circulating lymphocytes that react to self
- apoptosis following activation
- anergy (cellular inactivation due to weak activation with no co-stimulus)
peripheral tolerance
121
What 4 factors can make someone more vulnerable to developing an autoimmune disease?
- genetic predisposition
- environmental factors
- hormonal factors
- changes in immune system
122
What are the seven theories of mechanisms of developing an autoimmune disease?
1. forbidden clone
2. altered antigen
3. sequestered antigen
4. immunologic deficiency
5. genetic influence
6. molecular mimicry
7. hygiene hypothesis
123
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- lymphocytes mutate during maturation producing 'forbidden patterns'
- forbidden patterns mount immune response to host cells
forbidden clone theory
124
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- environmental factors (chemical, biological, physical) alter host cells to render them non-recognisable as self and therefore mount antibody response
altered antigen theory
125
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- some areas of the body are immune privileged (eyes, testicles, foetus)
- trauma to one eye results in the release of sequestered intraocular protein antigens, released intraocular antigen is carried to lymph nodes and activates T cells, effector T cells return via bloodstream and encounter antigen in both eyes
- no contact with lymphocytes during development
- damage causes exposure in later life
- host cells recognised as foreign
sequestered antigen theory
126
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- mutation or loss of immunological regulatory functions (either general or specific) so that self behaves as foreign antigen eg. defects in regulatory T cell activity are associated with multiple sclerosis
immunological deficiency
127
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- certain immune disorders predominate in females and families
- genetic links have occurred between diseases and inherited Human Leukocyte Antigen
* remember - HLA gene complex encode proteins that make up the Major Histocompatibility Complex and short arm of Chromosome 6*
- predisposition to autoimmune disease mostly due to combined effects from multiple genes coding for:
- cytokines
- inhibitory T cell surface molecule
- complement
- toll-like receptor
- apoptosis
genetic factors
128
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- structural similarity between viral T cell epitopes and self-peptides lead to the induction of an auto aggressive T cell response
molecular mimicry theory
129
Fas (death receptor)
| Failure of apoptotic death of self reactive B & T cells, can lead to a condition called?
autoimmune lymphoproliferative syndrome
130
AIRE (autoimmune regulator)
| When absent, decreased expression of self antigens in thymus, can lead to a condition called?
autoimmune polyendocrinopathy
131
Which theory of the mechanisms of developing an autoimmune disease is this a brief description of?
- lack of exposure to pathogens in early childhood leads to defective development of self tolerance
- increased susceptibility to allergy
- increased asthma rates
hygiene hypothesis
132
Which hormone can trigger an autoimmune disease which is evidenced by; largest difference between gender is between menarche and menopause and disorders being exacerbated during pregnancy
- the theory is that circulating hormones alter immune response by influencing gene expression
oestrogen
133
What are the 2 sub categories of autoimmune diseases?
organ specific
and
non organ specific
134
Which type of autoimmune disease is being described?
- antibodies block/destroy nicotinic acetylcholine receptors at the neuromuscular junction in skeletal muscle
- aetiology: certain genotypes (HLA complex) and thymic follicular hyperplasia (express AChR and may possibly trigger autoantibody synthesis)
myasthenia gravis
135
The following signs and symptoms are of what autoimmune disease?
- muscle weakness that increases with exercise and improves on rest
- dropping eyelids
- double vision
- oropharyngeal weakness
- myasthenic crisis 15-20% > invasive ventilation
- shortness of breath
myasthenia gravis
136
Which type of autoimmune disease is being described?
- risk factors: female, African/asian decent
- chronic multi-system disorder, most commonly affecting women during their reproductive years, characterised by presence of anti-nuclear antibodies (ANA). Immune complexes deposit in blood vessels around body
- aetiology: poorly understood, familial aggregation, drugs (eg. sulfasalazine, carbamazepine) Epstein-barr virus, hormonal (oestrogen)
systemic lupus erythematosus
137
The following signs and symptoms are of what autoimmune disease?
- malar 'butterfly' rash on the face
- photosensitive rash
- fatigue
- fever
- oral ulcers
- alopecia
- arthritis
- abdominal pain
- raynauds phenomenon
- cardiopulmonary
- nephrosis
- thrombosis
- avoid dental procedures in patient with an active form of this disease
systemic lupus erythematosus
138
Which type of autoimmune disease is being described?
- risk factors: female, >60yrs
- vitamin B12 is required for formation of red blood cells, B12 absorbed in terminal ileum (requires intrinsic factor)
- intrinsic factor secreted from parietal cells in stomach
- gastric anti-parietal cell antibodies causes atrophy
- body unable to absorb vit B12 resulting in macrocytic anaemia
pernicious anaemia
139
The following signs and symptoms are of what autoimmune disease?
- lethargy
- dyspnoea
- glossitis
- oral ulceration
- neuropsychiatric
- yellow/blue blindness
- peripheral neuropathy
pernicious anaemia
140
Which type of autoimmune disease is being described?
- disease of the developing world; autoimmune process following infection with group A streptococci
- Jones criteria: carditis, arthritis, chorea, erythema marginatum and subcutaneous nodules
- chronic destruction of cardiac valves and resultant cardiac failure
- dental management: can be more sensitive to further inflammation to cardiac tissue due to past destruction with an infection for example following an XLA
rheumatic fever
141
Which type of autoimmune disease is being described?
- risk factors: female, rheumatic disease, >40yrs
- lymphocytic infiltration of exocrine glands and subsequent destruction
- aetiology: genetic factors (HLA), environmental (EBV, Hep C and human T-cell leukaemia virus), hormonal (oestrogen)
- dental management: prevention and treatment of dental caries, oral candidiasis and allergic mucositis
sjorgen syndrome
142
The following signs and symptoms are of what autoimmune disease?
- dry eyes
- dry mouth
- vaginal dryness
- dry skin
sjorgen syndrome
143
Which disease is caused by the following?
- antibodies against desmoglein, therefore epithelial layer breaks down
- superficial blistering in the oral cavity
- S at the end of its name can help to remember S for superficial
pemphigus vulgaris
144
Which disease is caused the following?
- anti-hemidesmosome antibodies
- epithelial layer lifts off
- D at the end of its name can help to remember D for deeper
pemphigoid
145
FILL IN THE BLANKS
| 1. ... is a chronic condition involving an abnormal reaction to an ordinarily harmless substance called an 2. ...
1. allergy
| 2. allergen
146
FILL IN THE BLANK
... is a small molecule that elicits an immune response only when attached to a large carrier molecule (usually a protein). The carrier molecule does not elicit a response by itself.
hapten
147
Which type of hypersensitivity reaction is the following?
- antigen presented to CD4+TH2 cells
- TH2 cell gets activated and releases cytokines including interleukin 4 and interleukin 5
- IL4 and IL5 recruit B cells and IgE formed
- IgE binds to mast cells and basophils sensitising them
- re-exposure leads to release of mediators (histamine, leukotrienes, PAF (platelet aggregation factor), prostaglandin) from granular cells 'degranulation'
leading to;
- vasodilation, increased blood flow
- smooth muscle spasm, bronchoconstriction (difficulty breathing)
- increased vascular permeability, increased fluid entering tissue space causing oedema
type 1 'anaphylactic'
148
What timeframe can a type 1 hypersensitivity reaction have a late response?
2-4 hours
149
What are the two types of type 2 (cytotoxic) hypersensitivity reactions?
1. complement-dependent reactions
| 2. antibody-dependent cell-mediated cytotoxicity
150
Which sub type of type 2 (cytotoxic) hypersensitivity reaction is the following?
- antibody is directed against antigen on host cells (such as circulating red blood cells) or extracellular materials (basement membrane)
- resulting Ag-Ab complexes activate complement
- cell lysis/extracellular tissue damage
complement-dependent reactions
151
Which sub type of type 2 (cytotoxic) hypersensitivity reaction is the following?
- low concentrations of IgG, IgM or IgE coat target cells
- inflammatory cells such as NK cells, monocytes and granulocytes then bind to the antibody Fc receptors
- cell lysis/extracellular damage
antibody-dependent cell-mediated cytotoxicity
152
What are 4 examples of a type 1 hypersensitivity reaction?
- asthma
- hay fever
- food allergy
- penicillin allergy
153
What are 4 examples of a complement-dependent type 2 hypersensitivity reaction?
- transfusion reactions
- autoimmune haemolytic anaemia
- erythroblastosis fetalis
- goodpastures syndrome
154
What are 3 examples of a antibody-dependent cell mediated cytoxicity type 2 hypersensitivity reaction?
- transplant rejection
- immune reactions against neoplasms
- immune reactions against parasites
155
Which blood group is known as the universal donor group?
group O blood type
156
Which blood group is known as the universal recipient?
group AB blood type
157
Which example of a complement-dependent type 2 hypersensitivity reaction is the following?
- type of anaemia in which the red blood cells (erythrocytes) of a fetus are destroyed in a maternal immune reaction resulting from a blood group incompatibility between the foetus and its mother.
erythroblastosis fetalis
158
Which type of hypersensitivity reaction is the following?
- immune complexes are formed by the combining of antigens and antibodies
- Ab-Ag complexes deposit throughout the body, including in blood vessels
- inflammation
- complement binding
- platelet aggregation
type 3 'immune complex'
159
What are 4 examples of a type 3 (immune complex) hypersensitivity reaction?
- systemic lupus erythematous
- rheumatoid arthritis
- acute glomerulonephritis
- farmers lung
160
Which example of a type 3 hypersensitivity reaction is the following?
- commonly occurs after streptococcus infection
- Ag-Ab complexes aggregate in small vessels of kidneys
- inflammatory reaction
- symptoms; haematuria (blood in urine), oedema, hypertension, fever
acute glomerulonephritis
161
Which example of a type 3 hypersensitivity reaction is the following?
- inhalation of biological material (hay, mould, grass etc)
- antibody formation
- Ab-Ag complexes deposit in alveolar walls
- inflammation in alveolar walls
- prolonged exposure leads to collagen deposition and decreased lung compliance
farmers lung
162
Which type of hypersensitivity reaction is the following?
- cell-mediated response (T lymphocytes)
- MHC II - antigen complex elicits macrophage response
- CD4+ T helper cells get activated and start to proliferate and initiate immune response
- reaction takes several days to develop
- proliferation of T cells
- inflammatory reaction
type 4 'delayed'
163
What are 3 examples of type 4 hypersensitivity reaction?
- allergic contact dermatitis
- autoimmune myocarditis
- Mantoux test
164
Which type of hypersensitivity reaction is the following?
- encompasses autoimmune disease > antibodies bind to specific cell target receptors
- not classically used as part of Gell and Coombs classification
type 5 'autoimmune'
165
What are 2 examples of type 5 'autoimmune' hypersensitivity reaction?
- myasthenia gravis
| - graves disease
166
Mnemonic to remember the 4 types of hypersensitivity reactions ACID?
A - anaphylaxis (type 1)
C - cytotoxic (type 2)
I - immune complex (type 3)
D - delayed (type 4)
167
Mnemonic to remember types of hypersensitivity reactions cell mediations EGGT?
E - IgE (type 1)
G - IgG (type 2)
G - IgG (type 3)
T - T cell (type 4)
168
What are the following signs and symptoms of?
- increased vascular permeability (hypotension, swelling)
- vasodilation (hypotension, redness)
- myocardial dysfunction (hypotension, cardiovascular collapse)
- altered smooth muscle tone (bronchospasm)
- activation of the autonomic nervous system (tachycardia, anxiety)
- increased platelet aggregation (recruitment of immune cells, SIRS (systemic inflammatory reaction syndrome)
anaphylaxis
169
What are the 6 skin symptoms of anaphylaxis?
1. urticaria (rash)
2. puritis (itching)
3. flushing (redness)
4. swelling of tongue/throat
5. chemosis (inflammation of the eyes)
6. rhinorrhoea (excess secretions from nose)
170
What are the 3 respiratory symptoms of anaphylaxis?
1. shortness of breath
2. wheeze
3. stridor (high pitched sound when breathing)
171
What are the 5 cardiovascular symptoms of anaphylaxis?
1. hypotension (reduction in blood pressure due to vasodilation)
2. tachycardia
3. dysrhythmia
4. coronary artery spasm
5. cardiac arrest
172
What are the following miscellaneous symptoms of?
- abdominal pain
- uterine cramping
- headaches
- vomiting/diarrhoea
- anxiety
- confusion
anaphylaxis
173
What is this the definition of?
| - the ability of an organism to cause disease
pathogenicity
174
What is this the definition of?
| - the extent of pathology (harm) caused by the organism
virulence
175
What are the 4 stages of bacterial pathogenicity?
1. ENTRY
portals of entry include mucous membranes, skin and parenteral
2. ADHERE
biochemical reaction between host and pathogen that allows pathogen to remain within the host
3. PENETRATE
escaping defence mechanisms of host
4. DAMAGE
final effect of pathogen which manifests as signs and symptoms of disease
176
What are the 2 microbial adhesion factors made from proteins or polysaccharides?
fimbrial - pilli protrude as hair-like structures from the bacterial surface (proteins)
afimbrial - proteins that make more intimate contact with the host cell
177
What is being described?
- coat of polysaccharides (sugar) ''slime''
- external to cell membrane
- protection against desiccation
- enhances ability of bacteria to adhere to host
- protection from phagocytosis
* does not allow opsonisation by antibodies
* 'frustrated phagocytosis' leads to enhanced inflammatory response
bacterial capsule
178
What are the two major groups of bacteria based on cell wall structure?
gram positive
and
gram negative
179
FILL IN THE BLANKS
... release toxins into circulation on cell death/lysis that can lead to septic shock (via activation of cytokines, complement and coagulation cascade)
cell wall components
180
Is gram positive or gram negative bacteria being described?
- cell wall component is lipopolysaccharide (LPS/endotoxin)
- primary receptor for endotoxin is CD14 on macrophages
- common microbes: E.coli, P aeruginosa and meningococci, P gingivalis
gram negative
181
Is gram positive or gram negative bacteria being described?
- peptidoglycan fragments and teichoic acid
- common microbes: staphylcoccus aureus, staphylcoccus epidermidis and streptococci, streptococcus mutans
gram positive
182
Toxins on the cell wall of bacteria are known as?
endotoxins
183
Toxins secreted by the bacteria are known as?
exotoxins
184
What are the 4 types of exotoxins?
1. A-B toxins
2. proteolytic toxins
3. pore forming toxins
4. other toxins
185
Which type of exotoxin is the following?
| - a subunit enzymatic activity; B subunit binding and delivery of the toxin into the host cell
A-B toxins
186
Which type of exotoxin is the following?
- break down specific host proteins which to lead to clinical manifestations of disease eg. Botulinum in Clostridium botulinum attack proteins responsible for neurotransmitter release > leads to paralysis
proteolytic toxins
187
Which type of exotoxin is the following?
| - pore-formation leads to cell lysis
pore forming toxins
188
Which type of exotoxin is the following?
| - disruption of host cell signalling pathways and structural integrity to establish and maintain infection
other toxins
189
Proteinaceous toxins (exotoxins) are enzymes delivered to eukaryotic cells via two different methods: ??
1. secretion into the surrounding extra cellular matrix
| 2. direct injection into the host cell cytoplasm
190
What condition can develop due to toxins produced by clostridium botulinum bacteria?
botulism
191
Is extracellular or intracellular invasion being described?
- microbe breaks down the barriers of a tissue to disseminate in the host while remaining outside of host cells
- enzymes degrade host cell molecules: hyaluronidase (cleaves proteoglycans in connective tissue), streptokinase and staphylokinase (breaks down fibrin clots), lipase (degrades accumulated host oils), and nuclease (digests released RNA and DNA)
eg. group A B-haemolytic streptococcus and S aureus
extracellular invasion
192
Is extracellular or intracellular invasion being described?
- microbe penetrates the cells of a host tissue and survives within host cell
- both phagocytic and non-phagocytic cell types can serve as targets for invasion
- some pathogens have intracellular lifecycle which absolutely requires a mammalian cell for growth eg. Chlamydia spp, and Mycobacterium leprea
intracellular invasion
193
What are 4 intracellular pathogens that like to live within the host cella and are therefore resistant to intracellular killing and intraphagosomal replication can occur?
- salmonella enterica
- brucella suis
- mycobacterium tuberculosis
- burkholderia cenocepacia
194
What are 5 extracellular pathogens with an intramacrophage stage and therefore resistant to intracellular killing?
- Yersinia pestis
- pseudomonas aeruginosa
- klebsiella pneumoniae
- bacillus cereus
- streptococcus pneumoniae
195
What are 3 examples of facultative intracellular bacteria? (capable of living either inside or outside of host cells)
- listeria monocytogenes
- salmonella typhi
- legionella
196
What are 4 examples of obligatory intracellular bacteria? (can only survive inside host cells, reliant on intracellular host resources)
- chlamydia
- rickettsia
- coxiella
- mycobacterium tuberculosis
197
What are the two ways in which pathogenic bacteria can ensure that they are regulating expression of virulence factors?
- sigma factors
| - two component systems
198
Which regulatory control mechanism used by pathogenic bacteria to control the expression of virulence genes is the following?
- protein subunits of bacterial RNA polymerases control initiation of transcription
- regulate prokaryotic gene expression in response to microenvironment
sigma factors
199
Which regulatory control mechanism used by pathogenic bacteria to control the expression of virulence genes is the following?
- sensor protein embedded in the bacterial membrane 'senses' different physiological conditions of bacterial cell
- response regulator which binds to the promotor region of a gene to activate or repress transcription
two component systems
200
What is being described?
- the rapid and dramatic changes in genetic makeup of bacterial genome
- incorporation of genetic elements transferred from a donor organism to form genomic 'pathogenicity' islands usually large blocks of virulence determinants
- primary mechanism for antibiotic resistance (transformation, transduction, conjugation)
horizontal gene transfer
201
What are the 3 common types of antimicrobial resistance mechanisms in bacteria?
1. those that modify the target site
2. those that alter uptake of the antibiotic
3. those that inactivate the antibiotic
202
Acquisition of resistance occurs by two processes?
spontaneous mutations
and
horizontal gene transfer
203
What are 5 ways of combatting antibiotic resistance?
1. ensure hands, instruments and environment are clean
2. only prescribe & dispense antibiotics when they are needed, according to current guidelines
3. report antibiotic-resistant infections to surveillance teams
4. educate patients about how to take meds correctly, resistance & dangers of misuse
5. educate patients about preventing infections (hand washing, vaccines, covering mouth and nose)
204
What is the term used for the following?
| - direct uptake and incorporation of exogenous genetic material from one bacteria to another via the cell membrane
transformation
205
What is the term used for the following?
| - viral transfer of DNA from one bacterium to another
transduction
206
What is the term used for the following?
| - transfer of genetic material between bacterial cells by direct cell to cell contact (bacterial mating)
conjugation
207
What are the 4 processes in which viral pathogens infect host cells?
1. implantation (portals of entry include mucous membranes, skin, parenteral)
2. local replication and spread (replication within the initially infected host cell)
3. dissemination (via bloodstream or nerves)
4. multiplication at target organs (clinical manifestations present from disease to death)
208
What are the 2 mechanisms in which viruses can change in order to avoid the bodies immune system?
viral antigenic drift
and
viral antigenic shift
209
Which mechanism of how viruses can change to avoid the immune system is the following?
- evolutionary/variation mechanism by which viruses mutate the genetic code for antibody-binding site morphology
- creation of new virus, not effectively targeted by pre-existing antibodies
- influenza a, b and c glycoproteins differ between flu subtypes (eg. H1N1, H3N2, H5N1)
- seasonal variation of flu strains (and hence vaccination)
viral antigenic drift
210
Which mechanism of how viruses can change to avoid the immune system is the following?
- the combination of >2 viral strains to form new virus with combination of both surface antigens
- occurs only in influenza A
- results in major reorganisation of strains
- responsible for jumping between species and pandemics
- one species passes viral strain to intermediate host animal, a human also passes on separate strain to same animal. Genes from both strains combine to form new strain which can jump from intermediate host to humans
viral antigenic shift
211
What is the main difference between antigenic shift and antigenic drift?
Antigenic drift involves the accumulation of a series of minor genetic mutations
Antigenic shift involves “mixing” of genes from influenza viruses from different species
212
What are 5 other escape mutation mechanisms to escape host immune response?
- sequestrian (infection of host cells to store their genetic information without cytolytic consequence-virus remains in latent state until some event occurs (eg. HIV etc)
- blockade of antigen presentation (viruses may interfere with mechanisms leading to antigen presentation eg. block synthesis of MHC molecules etc)
- cytokine evasion (viruses may encode mimics or homologs of normal cytokines and their receptors, which bind to or replace the normal cell counterparts rendering them inactive or dysfunctional)
- evasion of NK cell immunity (virus can encode analog of MHC molecule - vetoes the killing process through spurious recognition of a phony molecule)
- inhibition of apoptosis by viral proteins (virus proteins may up-regulate proteins that inhibit apoptosis, blockade of apoptosis by altering cellular events)
213
What is the term used for congenital/genetic immunodeficiencies?
primary immunodeficiency
214
What is the term used for acquired immunodeficiencies (by disease, drugs or environmental exposure)?
secondary immunodeficiency
215
What are the 6 primary immunodeficiencies?
1. 'pure' T cell disorders
2. complement deficiencies
3. 'pure' B cell disorders
4. severe combined immunodeficiency
5. combined immunodeficiency
6. phagocyte deficiencies
216
Which type of primary immunodeficiency is the following?
- categorised into presence/absence of T cells and B cells
- may also have normal T cell count
- if associated with neurological findings may be life threatening
- SCID, Wiskott-Aldrich syndrome, DiGeorge syndrome, ataxia-telangiectasia and X-linked lymphoproliferative disease
combined immunodeficiency
217
Which type of primary immunodeficiency are the following clinical presentations of?
- < 12 months
- chronic diarrhoea
- failure to thrive
- severe, recurrent infections with opportunistic pathogens
- skin rashes
combined immunodeficiency
218
Which type of primary immunodeficiency is the following?
- 1 in 100,000 live births
- can be X-linked or autosomal recessive
- multiple variants of genetic mutations responsible
- early diagnosis imperative
- without treatment, fatal within first year
- treated with stem cell (BM) transplant, gene therapy, enzyme replacement therapy
- do not give live vaccines
severe combined immunodeficiency
219
Which type of primary immunodeficiency are the following clinical presentations of?
- recurrent infections
- failure to thrive
- chronic diarrhoea
- absence of lymphoid tissue
- poor weight gain
- diffuse erythematosus rash
- microcephaly
- skeletal abnormalities
severe combined immunodeficiencies
220
What are 3 risk factors for severe combined immunodeficiency?
- family history of infant death
- family history of SCID
- consanguinity
221
What is the name of the following condition associated with combined immunodeficiency diseases?
- X-linked condition characterised by thrombocytopenia
- small platelet size is consistent feature
- eczema, recurrent infections and easy bruising
- autoimmunity complicates up to 70% of cases
- increased risk of haematological malignancies
Wiskott-Aldrich syndrome
222
What is the name of the following condition associated with combined immunodeficiency diseases?
- deletion in chromosome 22
- neurological, immunological, endocrinological or cognitive deficits
- treatment modalities depend on clinical manifestations present in the individual patient
- management is symptomatic
DiGeorge syndrome
223
Which condition are the following clinical presentations of combined immunodeficiency?
- cyanosis
- heart failure
- bulbous nose tip and prominent ears
- cleft lip/palate
- learning disorder
- growth failure
- frequent infection
- classic triad of presentation: cardiac anomalies, hypo plastic thymus, hypocalcaemia
DiGeorge syndrome
224
Which type of primary immunodeficiency is the following?
- most common type of primary immunodeficiency
- heterogenous group of disorders characterised by increased susceptibility to respiratory tract infections with bacteria, particularly streptococcus pneumonia and haemophilus influenzae
- reduced/absent serum Ig levels or normal levels with impaired function
- eg. XLA (bruton syndrome, common variable immunodeficiency, selective IgA deficiency)
B cell immunodeficiency
225
Which type of primary immunodeficiency are the following clinical presentations of?
- > 6m of age with recurrent infections
- diarrhoea
- fatigue
- autoimmune manifestations
- sensorineural hearing loss
B cell immunodeficiency
226
What are the following conditions associated to which type of primary immunodeficiency?
- XLA (bruton syndrome) - inability to mature B cells
- common variable immunodeficiency - gene deletion for surface proteins and cytokine receptors, lack of IgG, IgM, IgA
- selective IgA deficiency - undetectable IgA, most common genetic primary immunodeficiency
B cell immunodeficiency
227
Which type of primary immunodeficiency are the following conditions associated with?
- chronic granulomatous disease
- hyper IgE syndrome
- leukocyte adhesion deficiency
phagocyte defects
228
Which condition associated with phagocyte defects is the following?
- severe infection
- abscess
- granuloma formation
chronic granulomatous disease
229
Which condition associated with phagocyte defects is the following?
- chronic dermatitis
- recurrent severe lung infection
- bone fragility
- failure to lose primary teeth
hyper IgE syndrome
230
Which condition associated with phagocyte defects is the following?
- recurrent severe bacterial infections
- poor wound healing
leukocyte adhesion deficiency
231
Which bodily fluids is HIV transmitted via?
- blood
- sexual fluids
- breast milk
232
What are the 4 HIV stages of presentation?
1. acute seroconversion
2. asymptomatic clinical latency
3. symptomatic period (milder immune dysfunction)
4. severe immunodeficiency and AIDS
233
What are 9 main symptoms of HIV seroconversion?
1. fever
2. malaise
3. athralgia
4. loss of appetite
5. rash
6. myalgia
7. pharyngitis
8. oral ulceration
9. loss of more than 2.5kg weight
234
What are 5 signs and symptoms of AIDs?
- encephalopathy
- candidiasis of oesophagus
- candidiasis of upper airways
- chronic herpes simplex
- HIV wasting syndrome
235
What are 4 methods of HIV management?
1. antiretrovirals
2. counselling for the patient
3. vaccinations
4. micronutrient supplementation
