Case 9 Flashcards
(199 cards)
1
Q
What is a standard deviation and what does it mean if it is particularly large or small ?
A
Variation around the mean.
Small = data is closely grouped
Large = data is sparsely grouped
2
Q
If the data peak was on the left of the data, with a long tail to the right, what type of skew would it be called ?
A
Positive skew. Most values are greater than the value at the peak.
3
Q
What does a z score show and how is it calculated (might help realise what it shows)
A
How many SDs a value is above (or below) the mean. Shows the rarity or particular value.
z = (value - mean) / SD
4
Q
What would a birth weight on the 10th centile mean in terms of relation to other children ?
A
Lighter than 90% of comparative children
5
Q
What is the formula for BMI calculations ?
A
BMI = weight/height^2
6
Q
What is another way of referring to +ve sense single stranded RNA ?
A
mRNA
7
Q
A virion containing what type of nucleic acid would be least likely to have enzymes to make mRNA ?
A
+ve sense single stranded RNA, same base sequence as mRNA so wouldn’t need to replicate
8
Q
What does the +ve/-ve sense of a nucleic acid refer to?
A
The 5’ or 3’ direction at which replication occurs.
9
Q
What is a major property of an enveloped virus ?
A
Can utilise membranes of host cells and cause syncytia formation.
10
Q
What is the envelope made of in enveloped viruses and what can it resist ?
A
Lipids (Fusogenic glycoproteins) so fragile and disintegrates quickly. Can still resist GI tract pH.
11
Q
Why might visions not be able to be viewed using a regular light microscope ?
A
They are smaller than the wavelength of visible light
12
Q
Why do DNA viruses mutate less frequently than RNA viruses ?
A
DNA polymerase gives a proof reading function whereas RNA doesn’t so more likely to mutate.
13
Q
What drugs are likely to be involved in the treatment of Hep C ?
A
Sofosbuvir, Ledipasvir and Ribavirin
14
Q
What are the general actions of Sofosbuvir, Ledipasvir and Ribavirin ?
A
Sofosbuvir, nucleotide analogue that inhibits RNA polymerase
Ledipasvir, inhibits viral replication
Ribavirin, Blocks RNA synthesis
15
Q
What are the classic symptoms of Measles and what will develop within 2-5 days ?
A
4 day fever and cough. Red pharynx with white spots
Rash will develop in 2-5 days.
16
Q
Why is a secondary bacterial infection common after an initial viral one ?
A
Immune system is temporarily exhausted/compromised
17
Q
How would bacterial pneumonia present in a px ?
A
Almost like a secondary infection because bacterial one is delayed. Affected alveoli on X-ray.
18
Q
What viral infection may lead to bronchiolitis and what would be seen on X-ray ?
A
RSV (respiratory syncytial virus) . Peribronchial thickening on X-ray.
19
Q
What is the difference between antigenic shift and antigenic drift ?
A
Antigenic shift = pandemic by reassortment (worldwide, like the game)
Antigenic drift = epidemic
20
Q
What prophylatic treatment is taken to prevent pandemics from occurring ?
A
Vaccination
21
Q
What is the typical presentation of glandular fever (4) and what is a common viral cause ?
A
Sore throat, difficulty swallowing, enlarged cervical lymph nodes with splenomegaly.
Epstien-Barr virus.
22
Q
What types of HPV can cause ; common warts, cervical cancers ?
A
Warts = 6 and 11 Cancers = 16 and 18
23
Q
Which of the hepatitis viruses can be spread by contaminated food and water ?
A
Hep A and E
24
Q
What type of infection does HPV cause ?
A
Local infection of specific host tissues
25
What does the Coxsackie A virus cause ?
Herpangia, hand foot and mouth disease
26
Which of the hepatitis viruses can you not be directly infected by ?
Hep D, must have had Hep B first
27
Which of the heps can you vaccinate against ?
Hep A and B
28
Which hep can exacerbate another type of Hep?
Hep A worsens Hep B
29
Which hep are hepatocarcinomas most likely to arise from?
Hep C
30
What is HIV made of and how does it replicate ?
Made of two copies of +ssRNA
| Has to integrate into chromosome of cell in order to be reproduced
31
How might you monitor a px with Hep B ?
Blood plasma for quantitive PCR to determine viral load.
32
What further tests would be run on an HIV +ve px and why ?
Blood sample PCR and blood sample flow cytometry.
| Want to see viral load to see if the CD4+ cell count is decreasing.
33
What virus is associated with hemorrhagic fever?
Dengue virus
34
What does the Ebola virus cause and what is its animal reservoir ?
Hemorrhagic disease with high pathogenicity
| Fruit fly bats
35
What are the consequences of being infected once by dengue fever ?
Shouldn't return to places where it's present
36
What are the 9 protected characteristics as defined by the equality act ?
Age, Disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religious beliefs, sex, sexual orientation/attraction
37
When a bacteria enters through breach in perineal cavity what happens? (detection, activation, secretion)
Resident macrophages are activated through PRRs (pathogen recognition receptors). This leads to secretion of TNF-a, IL8 and IL-6
38
What are the general actions of TNF-a and IL-8 ?
TNF-a , makes the endothelium more permeable (leaky)
| IL-8, initiates direct recruitment of neutrophils
39
Plasma enters through the endothelium and activates what pathways ?
Lectin and alternative
40
What is the function of cDCs and what happens when they mature ?
Phagocytosis and pinocytosis (ingestion of liquid into a cell by budding of small vesicles from the cell membrane)
Migrates to draining lymph nodes.
41
How is clonal expansion triggered in a T cell ?
Antigen presentation MHC 2 by cDCs to circulating naive T cells in draining LNs. Appropriate T cell with correct TCR then replicated.
42
When CD4 Th17 cells traffic to the site of infection they release... which acts to .... ?
IL-17 , increases neutrophil recruitment and production
43
What immunoglobulin do B cells secrete once they're activated in draining LN ?
IgM
44
B cells initiate the endocytosis of surface antigens. They then do what with the fragments ?
Present to MHC 2 to cognate TFH cells. They then help more B cells to undergo somatic hypermutation and class switching
45
What occurs after a bacterial infection (e.g. E coli) has been cleared ?
Memory B and T cells are produced against E coli
46
Viral infections are presented to epithelium cells through what process ?
They adhere to the cells in the lungs by the mucous and cilia
47
What is the action of cilia against respiratory viruses ?
Sweep the virus to the upper respiratory tract for exhalation.
48
What is the action of a viral infection e.g. influenza A on respiratory cells ?
acute cell death of respiratory epithelium cells. Removes mucous secreting cells and blocks the function of mucociliary escalator
49
What do infected cells and plasma DCs produce that initiates an IFN response ?
Type 1 interferons (a and b). bind through auto and paracrine methods. Inhibits viral replication and protein synthesis.
50
IFN also induce proliferation/activation of NK cells which do what ?
Induce direct killing of viral cells
51
What is the function of IL-12 and what structures secrete it?
Activates NK cells to produce IFN-y which increases APCs antigen processing.
Produced by activated antigen presenting cells eg. macrophages and dendritic cells.
52
What class of MHC is presented to CD8 cells lymphocytes ?
MHC class 1 (always add up to 8)
53
What is the action of B cells on viral infections ? (action, where, presentation, action)
Endocytose virus in draining LN and present on MHC 2 to CD4+. CD4 then stimulate specific B cells to undergo somatic hypermutation and class switching.
54
What is a common virus that can be transmitted across the placenta ?
Rubella
55
What are the 3 methods of non contact transmission ?
Airborne (aerosol) , vechile Bourne (Food e.g. salmonella) and vector Bourne (mosquitos)
56
What is the definition of isolation ?
When an individual is known to have a given infection they are removed from general population to prevent further spread of infection.
57
What is the definition of quarantine ?
A group of people who don't have a given illness but may be incubating it from somebody else who had it. May show signs later and have been infecting others without knowing so kept away as a prevention incase.
58
What is an emerging infection ?
a new , re-emerging or drug resistant infection whose incidence in humans has increased in the last 20 years or is predicted to increase in the future.
59
List some causes of a new emerging infection ? (6)
change in environment, war, international traffic (traded goods) , new tech (food GM) , bioterrorism, eco changes (global warming)
60
What is a vital component of a pandemic virus ? (4)
Must be able to replicate in humans and cause serious illness that can spread effectively from person to person. Most of the population can't be immune
61
Name two common antiviral drugs
Oseltamivir and zanamivir
62
What is the average weight, height and OFC of a newborn ?
Weight = 3.5 Kg
Height = 50cm
OFC (occipital frontal circumference) = 35cm
63
How much weight does a newborn lose on average in the 3-5 days after birth? when should they regain the weight by ?
5-10%
| 10th day
64
What are the 4 modalities of developmental milestones ?
Gross motor function, fine motor function, hearing/vision, communication/social
65
What is the formal assessment of growth ?
SOGS, schedule of growth skills. Refer to paediatrician if concerns arise.
66
What are the 4 common reflexes assessed in a newborn ?
```
Tonic neck (looking in each direction)
Grasp reflex (grip fingers)
Step reflex (walking)
Crawl reflex
```
67
What are the key developments after 3 months ?
turns head side to side. opens hands momentarily. brief hold gaze, particularly in mum. crying. recognise mum with a social smile
68
What are the key developments after 6 months ?
rolls prone to supine. holds objects briefly. follows moving objects across midline. holds bottle firmly. spontaneous smile. Gurgling
69
What are the key developments after 9 months ?
crawling. finger feeding. Tracks movements. pointing. recognises and responds to own name. waves and clasps objects
70
What are they key developments in a 1 year old ?
walk briefly, crawls up stairs. pinsor grip. eats with spoon. protective of toys, enjoys pictures and blocks
71
What are the key developments in a 2 year old ?
Run, start, stop, kicks. Hand preference starts to show. Recognises faces. Starts to self dress. Drinks from cup. 50 word vocal 2 word phrases.
72
What is the need for vaccination of mothers against the whooping cough ?
Can pass to infants and adolescents where the risk/prevalence is high. IgG from mum's immunity goes to baby, gives protection for 2 months until they get vaccine.
73
What is the function of Th1 in bacterial infections ?
help macrophages kill intracellular bacteria and Ig class switch (want IgA)
74
What is the function of Al salts in the whooping cough whole cell vaccine ?
Acts as an adjuvant. holds antigen in place at the site of vaccination to give time for DC to come and sample the antigens
75
When do you give a pregnant women the whooping cough vaccination ?
28-32 weeks, enough time for immune response and transferal of IgG to take place
76
If the mother has had a previous child or been vaccinated against whooping cough in the past does she still need the vaccine ?
Yes, the immunity decreases over time so boosters are necessary.
77
What is the general function of adjuvants ?
Make the vaccine stronger. Modifies effects of other parts of the vaccine
78
What response do the adjuvants favour ?
Th2 > Th1
79
Th1; what cytokine does it release, what immune reactions does it trigger, what host defence does it control ?
IFN-y
Macrophage and B cell activation
Intracellular microbes
80
Th2; what cytokine does it release, what immune reactions does it trigger, what host defence does it control ?
```
IL-4, 5 and 13
Mast cell (eosinophil activation) IgE production
Helminthic parasites
```
81
Th17; what cytokine does it release, what immune reactions does it trigger, what host defence does it control ?
IL-17, 22
Neutrophil/monocyte activation for inflammation
Extracellular bacteria and fungi
82
What is the difference between MHC 1 and 2 relative to antigen presentation ?
MHC 1 = presenting peptides from inside the cell
| MHC 2 = presenting antigens from outside the cell
83
Why do organ transplants have to be properly tested ?
Host T cells reject foreign MHC due to different structures so organ would fail and potentially damage other structures
84
What is the critical vaccine coverage and what is its given formula ?
Proportion of immune individuals needed in a population to decrease the frequency of a disease.
1-(1/Ro) where Ro is number of 2ndry infections from first individual
85
Would a highly infectious disease have a low or a high Ro?
Very high, for example measles.
86
Bacteremia can be described as an opportunistic infection, what does this mean ?
Only becomes infectious if it enters the blood or the CSF
87
What specific structures do T and B cells exclusively recognise ?
T cells = only proteins
| B cells = only polysaccharides
88
What is a conjugate ?
A protein has been added to a structure eg. a polysaccharide
89
How would a polysaccharide conjugate be broken down and displayed ?
B cell endocytose the protein along with the pathogen and displayed to T cell to initiate a response to conjugate vaccine
90
Where are T (fh) cells found and what is their function?
Subset of CD4 cells found in draining LNs. Activate induced cytokine deaminase. This allows B cell to undergo isotope class switching and somatic hypermutation
91
What area of the immunoglobulin changes during somatic hypermutation ?
Changes in fingertip (variable regions) from random mutations
92
What immunoglobulin will be produced in response to a polysaccharide vaccine ?
Just IgM as no class switching will occur. This is because T cells haven't been stimulated because they only see proteins.
93
What region changes during class switching ?
Constant region.
94
What type of progenitor gives rise to NK, T, B and plasma cells ?
Common lymphoid progenitor
95
What is the bacterial capsule made of ?
Layer of polysaccharide and glycoproteins outside the plasma membrane
96
What is the function of the bacterial capsule ?
Prevents recognition of surface molecules, forces immune system to produce capsule specific antibody to allow phagocytosis of bacteria
97
What are pili and what is their function ?
glycoprotein projections used for attachment to epithelia.
| Promotes bacterial entry
98
What is present in GRAM +ve bacteria which colour them to stain what colour ?
Peptidoglycan walls, stain purple Because it retains the crystal violet.
99
What do the following shapes mean about the different bacteria ; cocci, bacilli, spirochaete, vibrio
```
cocci = spheres
Bacili = rods
Spirochaete = spirals
Vibrio = comma / curve shaped
```
100
What is the alternative pathway and what type of reaction occurs ?
most used in absence of a specific antibody. C3b and C3 convertase at microbial surface activates CR1 on phagocyte granules -> opsonisation -> phagocytosis
101
In the manose binding lectin pathway what two structures bind together to form manose ?
C2 and C4
102
What is the action of C5a ?
Increases vessel permeability and is a chemotactic factor for neutrophils (increase in neutrophil number)
103
What forms the membrane attack complex and how what is it's action ?
C5b + C6-C9 .
| Inserts into the bacterial membrane causing lysis
104
What is anaphylaxis ?
Wide spread mast cell degranulation and basophil activation in response to allergens and IgE response.
105
How are macrophages activated ?
PRRs (TLR is major group) binding to PAMPs
106
What are the 4 major cytokines that macrophages release and what are their general actions ?
IL-1, acts on hypothalamus for fever
IL-6, goes to liver to form acute phase proteins
IL-8, endothelium to cause neutrophil chemotaxis
TNF-a, goes to endothelium to increase permeability and adhesion of certain molecules
107
How are dead cells removed during apoptosis ?
Phagocytosed by macrophages using ATP in a non inflammatory response.
108
How are dead cells removed during necrosis ?
Inflammatory response. production exceeds macrophage capacity. Pus and abscess form.
109
What is chronic lymphocyte leukaemia ?
Uncontrolled proliferation of differentiated B cells. Overcrowds the bone marrow and invades other organs
Leads to hepato spleno megaly. Slow progress px may not realise they're affected/won't need treatment for years.
110
What is the action of CD4 Th1 (what response, what does it activate, using which receptor, what does it secrete)
intracellular bacteria responses (macrophage activation using MHC 2).
Secretes IFN-y and TNF-a
111
What is the action of CD4 Th2? (what response, what does it clear, what does it secrete)
Antibody (B cell) response, clearance of extracellular bacteria.
Secretes IL-4, 5, 13
IL-5 , responsbile for antibody formation.
112
How does the cytokine environment affect the type of T cell that is formed ?
IL-12 = Th1
| IL-2 and 4 = Th2
113
Where is the MHC2 receptor synthesised and what is it's pathway from there ?
Synthesised in the ER before it goes to the Golgi apparatus and binds to fragments
114
How is the spleen divided ? (pulp)
Islands of white pulp (lymphatic component) interspersed through red pulp (chords of billroth)
115
How does the antibodies in px show the type of infection present ?
IgM, IgM and IgG, IgG
IgM, acute infection
IgM and IgG, chronic active infection
IgG, previous exposure/immunisation
116
What cytokine produced by macrophages helps to maintain the T cell ?
IL-12
117
Which of the Hep viruses are acute, chronic or both ?
Hep a, e = acute
Hep b = both
Hep c = chronic
Hep d = only with hep B
118
What is the direct action of IFN-y ?
Causes direct recruitment of inflammatory cells
119
What are the actions of the enzymes perforin and granzyme ?
Perforin, causes pore formation in cell membrane
Granzyme, enters target cell and activates apoptosis
Releases IFN-y and IFN-a/b
120
What is Epstein Barr virus ? (what does It cause, how does it present acute and chronically)
Herpes virus that causes latent infection (never cleared)
Acute = infection mononucleosis (common=glandular fever)
Chronic = increased risk of head and neck cancers
121
What does normocytic anaemia indicate ?
normal RBC size. Can be a chronic disease that is characterised by bone marrow and renal failure. Can cause acute blood loss for example in pregnancy.
122
What does microcytic anaemia indicate ?
iron deficiency due to small RBC for example in sickle cell anaemia.
123
What does macrocytic anaemia indicate?
Large RBC, folate and B12 decrease. Haemolysis, hypothyroidism and liver disease are related.
124
What is the cause of thalassemia? what does it result in?
Error in production of B chains in the bone marrow.
| Chronic haemolytic due to unstable membranes
125
What are the minor and major types of thalassemia ?
```
Minor = 1 B chain allele affected so asymptomatic
Major = both chains affected , transfusion dependant
```
126
How do ferritin levels indicate IDA and inflammatory responses ?
Shows total body iron stores
Low = IDA (Iron def anaemia)
High = acute inflammatory response
127
What is transferrin and what do high levels indicate ?
Iron transport protein, shows the total iron binding capacity.
High in IDA
128
What does the transferrin saturation level show ?
% of transferrin that is bound to iron. Decreased in IDA
129
When are the two MMR injections recommended ?
Within month of first bday
| Booster between 3 and 5 years old.
130
Why can some infections never be eliminated e.g. tetanus?
Always have non human sources eg. animal host, environmental reservoir.
131
What is the problem with an attenuated vaccine ?
It is still live even through in a mild form so may cause the disease, especially in an immunocomprimsed px eg. MMR.
132
What is the correlation between vaccine similarity to the disease and triggered immune response ?
The similar a vaccine is to the disease, the greater the immune response.
133
How and when is the flu vaccine issued ?
Single IM dose of the new vaccine given each year between Sept-Dec.
134
RSV and PIV are both common resp viral pathogens. Which part of the resp tract do they infect and what is their structure ?
Both single stranded -ve sense RNA.
RSV, paramoxivirus. severe lower resp tract eg. bronchitis. Mostly in kids >3 y/o
PIV, upper resp tract with fever, cough, rhinitis. Mostly in kids under 3 y/o
135
The flu virus has segmented RNA packaged in nuclear protein which means that ....
RNA has multiple pieces spread across the genome
136
The flu virus has a lipid envelope with two surface proteins. What are the names of these proteins ?
Hemagglutinin and neuraminidase
137
What is genetic reassortment and what does it lead to ?
Shapes a gene segment so previous response is now useless. Leads to antigenic shift, pandemic is possible
138
Why might birds being the major carrier of the flu virus lead to an increased chance of genetic reassortment ?
Birds spread the virus to other animals e.g. pigs. 2+ viruses reassort and produce a new virus that passes on to humans and causes infection.
139
What is the action of neuraminidase during flu treatment?
Enables virus to be released from cell surface. viruses can't escape cell so replicate and inhibit neuraminidase. Keeps virus away from lower resp tract and decreases aerosol load
140
What is the action of aminitidine in flu treatment ?
Blocks M2 pore ion channel located with viral envelope, preventing replication.
141
What is the proper name given to the red rash with white spots that is typical in measles infections ?
Enanthema with Koplik spots
142
What is the chronic, incurable disease that arises if measles is not properly treated ?
Subacute sclerosis pan encephalitis
| Delayed CNS disease, measles projects into brain tissue. CSF contains increased measles virus antibody.
143
What is the incubation time of Hep C ?
2-26 weeks
144
What is the function of the capsid ? what are the 3 types of capsid ?
Protects nucleic acid from virus, stops GM from drying out and degrading. Easy to dissemble therefore quickly active once inside the cell.
Helical (flu) , icosahedral (adenovirus) and complex (poxvirus)
145
What are the 3 methods in which visions move to other cells ?
Cell free release, direct cell cell transfer , syncyntia
146
What is syncsyntia ?
2 cells fuse with one large outer membrane allowing the virus to move across. New cells then fuse, virus moves further through enlarging multinucleate structure.
147
What is the difference between localised and systemic infections ?
Localised, replication limited to region adjacent entry site. local damage against local immunity eg. flu. If immune response doesn't occur it can develop into ...
Systemic, infection spreads to other systems via lymph nodes eg. blood (Viraemia) and rest of body. Long incubation period
148
What is the difference between horizontal and vertical spread ?
Horizontal, not related to infected. Passed through infected air, food, water etc
Vertical, related to infected. Passed through ovum, sperm, placenta or milk to next generation.
149
What is the name of the virus that causes chickenpox? what is its reactivation called ? how is it prevented ?
Varicellular zosto virus
Shingles , possible to catch chickenpox from shingles
Antivirals can't cure, live attenuated VZV vaccine used.
150
What does Kaposi's sarcoma virus cause and which px group does it most commonly effect?
Skin lesions
| occurs in immunosuppressed px and genetically susceptible.
151
Where does cytomegalovirus reside when latent ?
Bone marrow and circulating monocytes
152
Which antivirals can be used to treat CMV?
Ganciclovir , fascornet and cidofovir
153
What is the cause of 90% of anal cancers ?
Type 16 HPV
154
What virus is commonly transmitted by mosquitos ?
Dengue fever
155
What is the treatment for DHF ?
No effective antivirals or vaccine. Uses antibody enhancement (ADE)
156
What are the stages of ADE ?
1st infection with subtype 1, antibody binds to virus preventing it from infecting cells. macrophages recruited and destroy virus
2nd infection with subtype 1, same response with pre existing antibodies
2nd infection with subtype 2, no neutralisation. Macrophages recruited by also become infected.
157
How quickly is the immediate innate response initiated ?
0-4 hours
158
List 3 preformed soluble effector molecules that are involved in the immediate innate response ?
Defensins, lactoferrin and lysozyme
159
What does the cytolytic action of flu A cause ?
acute cell death of dilated resp cells. Removes mucous secreting cells, blocking the mucociliary escalator
160
What two things do NK cells release to kill virally infected cells ?
Perforins and granzymes
161
Where are immature dendritic cells and macrophages positioned ?
Areas vulnerable to microbes eg. skin and mucosal layers
| Nasal passages, throat, intestines and genitals
162
Name two endosomal location receptors and which structures they detect ?
TLR-7 , single stranded RNA
| TLR-9, recognises herpes virus
163
TLRs .... (4) are prototypic , involved in viral recognition and are primarily expressed on .... ?
3, 7, 8, 9
| Immune cell endosomes
164
What is the classical triad of triggering TLRs ?
Pyrexia, persistant parhyngitis and cervical lymphadenopathy
165
What symptoms do IL-1 and 6 cause ?
Fever
166
How is temperature changed to effect virus replication ?
Virus replication is temp sensitive, increasing temperature decreases replication
167
Which cells can produce IFN-a+b , what is their surface effect on infection ?
All types of cells
| Causes systemic symptoms associated with infection; malaise, myalgia etc.
168
What is the effect of IFN when they're bound to receptors ?
indices resistance to viral replication in all cells. ^ expression of ligands for receptors on NK cells. Activates NK cells to virally infected cells
169
What is the action of IRFs ?
Interferon response factors
| phosphorylated and enter nucleus to initiate interferon mRNA synthesis
170
What is the action of ISGs ?
IFN stimulated genes
| Suppress viral entry, viral replication and alter cellular metabolism
171
How do IFNs produce an 'antiviral state' ?
bind to receptors on mast cells, trigger JAK/STAT activation and transcription of ISGs.
All genes involved in viral life cycle so perform variety of function to block replication.
Can pass to neighbouring cells to create 'cellular firebreak' to infection.
172
Where are RLRs found and what can they induce ?
Found in mast cells
| Produce type 1 IFNs against virus that uncoats at plasma membrane
173
RLRs can detect abnormal RNA molecules and trigger a response. What RNAs would they consider 'unusual' ?
Double stranded RNA
| RNA that lacks 5' end cap of cellular mRNAs.
174
What is significant about pDC secretion relative to other cells ?
pDCs can secrete 1000 x more type 1 IFNS. Extensive rough ER.
175
Why couldn't the 3 MMR injections be given as single injections within a week of each other ?
IFN response to vaccine 1 would suppress vaccine 2 therefore immune response would be weakened and cover may not be given.
176
What is the minimum recommended time between live attenuated vaccines in order to avoid overlapping IFN responses ?
30 days
177
Why is the buttocks a poor location for vaccine administration
bad blood supply, poorly vascularised with a lower number of cDCs
178
How does the IM injection into the deltoid/quads affect the type of response ?
activation of cDCs in axillary and linguinal LNs respectively favours IgG. Less protection than IgA, only protects disease from developing.
179
What does TLR signalling do ?
Induces CCR7 and enhances processing of pathogen derived antigens.
180
What is the function of CCR7?
directs migration to lymphoid tissues and augments expression of costimulatory/MHC molecules.
181
What 'trial' do DCs follow in order to reach nearest draining LN?
Chemokine CCL21
182
What is the passage of lymph from all tissues through host structures and back into circulation ?
Lymph -> all tissues, R lymphatic duct (upper body) , thoracic duct (lower body) , R/L subclavian veins , circulation
183
Why is the spleen able to filter BBVs ?
Blood borne viruses
| No lymph drainage to spleen so lymphocytes required to directly enter spleen from blood.
184
If a vaccine is intended to activate T cells what must it contain ?
Proteins
185
What is cross presentation ?
CD8 response generated without the virus. endocytose material goes into cytoplasm and presented by MHC1 so cDCs don't need direct viral infection in oder to present viral antigens with MHC1.
186
Which TLRs are specifically directed to the endoscope following synthesis in ER ?
3,7,8,9
187
What do naive T cells require to become fully activated ?
Costimulation from B7 and CD28 along with signal through TCR to become fully activated by cDC
188
Which type of CD4 is specific to viruses ?
Th1 , leave LN traffic to infection site and assist/stimulate macrophages
189
What happens when B cells interact with CD4 T(fh) cells at border T+B cell areas of LN?
class switching, allows for somatic hypermutation in immunoglobulin gene.
190
.How does a B cell bind to a virus ?
Through a viral coat protein. Virus then internalised and degraded.
191
How do T and B cells interact in conjugate vaccines ?
CD40 (T) and CD40L (B). peptides from internal proteins of virus present to T cell, activates B cell produces antibody against viral coat protein.
192
Which two types of HPV cause genital warts and cervical cancer ?
Genital warts = 6 and 11
| Cervical cancer = 16 and 18
193
What is unique about the HPV vaccine ?
Normally strength of immune response is wild > live attenuated > inactivated > subunits. In HPV the vaccine is the strongest response.
194
What happens when a B cell receptor isn't cross linked ?
low affinity surface Ig.
| B cell receptor isn't cross linked and centrocyte cannot present antigen to T cell so enterocyte dies by apoptosis
195
What happens when a B cell is cross linked ?
High affinity surface Ig. B cell receptor cross linked antigen presented to T helper cell. Centroyte recipes help survives and divides
196
Why are booster vaccinations given ?
every time you vaccinate it increases the chance of generating an ^ affinity for antibody
197
What type of immunoglobulins are present in Anti A and B abs and anti Rh-d ?
Anti a and b = IgM
| anti Rh-d = IgG
198
What is the significance between ABO and Rhesus antigens ?
ABO antigens are carbs so no T cell response. Rhesus antigens are protein so T cell involved, B cells can undergo class switching
199
Why is the presence of B7 important in autoimmunity ?
Only present in infection so limits autoimmunity because naive CD8 require it to become fully activated
