Immunology 4 - Immune modulation 1

Question 1

Relationship between T helper cells and CD8+ T cells

Answer 1

Provide help to CD8+ T cells by secreting IL-2 (growth factor)

Question 2

APCs

Answer 2

Dendritic cells, macrophages, B cells

Question 3

Why is T cell memory response so gr8 compared to the primary immune response?

Answer 3

• Memory T cells continue to proliferate even in absence of Ag, longevity
• Memory T cells express different cell surface receptors which allow them to migrate to non lymphoid tissue where microbes enter
• Rapid robust response to subsequent antigen exposure (lower threshold of activation than Naive cells)

Question 4

Antibody class in re-exposure to antigen

Answer 4

pre formed IgG

Question 5

With the influenza vaccine, how is protection acquired? Which cell controls the viral load?

Answer 5

CD8 + T cells control the viral load (antibody provides protective response)

Antibodies targeted against Haemaggluttinin (HA) on influenza virus

Question 6

How can the antibodies in influenza be detected?

Answer 6

HA inhibition assay

Question 7

When do you get protection from virus and for how long after flu vaccine?

Answer 7

After 7 days, generally lasts for 6 months

Question 8

BCG type of vaccine

Answer 8

Live attenuated

Question 9

Which cell mediates the immune response to TB?

Answer 9

T-cell mediated

Question 10

What does BCG maiNLY provide protection against?

Answer 10

Some protection against primary infection but mainly to prevent progresstion to active TB

Question 11

mantoux test

Answer 11

 Inject a small amount of liquid tuberculin (AKA purified protein derivative / PPD) intradermally

• Re-examine site 48-72 hrs later
• +ve if >10mm (anyone)

Question 12

Examples of live attenuated vaccine

Answer 12

MMR BVOY
MMR
BCG
VZV
Oral - polio (Sabin)
Yellow fever

Question 13

Of the live attenuated vaccines, which are HIV safe and which aren’t?

Answer 13

MMR = HIV safe

BCG + Yellow fever = NOT SAFE

Question 14

Examples of inactivated vaccines

Answer 14

Influenza, cholera, polio (SalK), HAV, pertussis, rabies

Question 15

Examples of component/subunit vaccines

Answer 15

HbS antigen, HPV, Influenza (neuraminidase, HA)

Question 16

Examples of toxoid vaccine

Answer 16

Diphtheria, pertussis, tetanus

Question 17

Disadvantages of live attenuated

Answer 17

Disease conversion, storage issues, spread to contacts

Question 18

Advantages of inactivated/component/toxoid

Answer 18

Easier storage, lower cost, used in immunodeficient pts

Question 19

Conjugate vaccines = ?

Answer 19

Polysaccharide antigen target + protein target

Question 20

Examples of conjugate vaccines adn which bacteria do they provide immunity to?

Answer 20

Pneumococcus, Hib, meningococcus

Encapsulated bacteria

Question 21

Role of adjuvants

Answer 21

Increase the immune response without altering its specificity

Mimic the action of PAMPs on TLR and other PRRs

Question 22

Which adjuvant is most commonly used in vaccination of humans? How does it work?

Answer 22

Alum (hepA, hepB and HIb)
Antigens slowly released over time
Increased IL-4 secreiton which prime naive B cells

Question 23

CpG - what is it?

Answer 23

Adjuvant, cytosine bound to guanine with phosphate in the middle

CpG motivs bind PRR (TLR9) and induce immune response

Question 24

What kind of antigen is associated with better immunogenicity

Answer 24

Protein antigen, polysaccharide antigens are poorly immunogenic

Question 25

DNA/mRNA vaccine MOA

Answer 25

Injecting plasmid containing chosen genes into muscle cells -> protein exp on surface​ Mimic viral infection + stimulate T cell response

Question 26

aDVANTAGES AND disadvantages of DNA/mRNA vaccines

Answer 26

Faster to produce Disadvantages: DNA: plasmid can integrate in to host DNA --> AUTOIMMUNITY mRNA: hard to store as unstable

Question 27

Dendritic cell vaccines MOA and examples

Answer 27

MOA: take patients dendritic cells, load them with tumour antigen then reintroduce them in to the patient e.g. Sipuleucel T/provenge (Prostate cancer)

Question 28

indications for HSCT

Answer 28

SCID, leukocyte adhesion deficiency, haematological malignancy

Question 29

Indications for antibody replacement (IVIG)

Answer 29

``` GIVEN IV/SC, every 3-4 weeks Primary antibody deficinecy: Bruton's Hyper IgM CVID ```

Question 30

2 types of immunoglobulin based therapies used to boost the immune system?

Answer 30

Human normal IgG | Specific Ig

Question 31

Examples of specific Ig

Answer 31

VZIG, Rabies ig, HBV Ig, tetanus Ig

Question 32

3 examples of recombinant cytokines used to boost the immune response (cytokine therapy)

Answer 32

IFNa IFNb IFNg IL-2

Question 33

IFNa uses

Answer 33

CML, Hairy cell leukaemia, MM

Question 34

IFNb uses

Answer 34

Behcets, relapsing MS

Question 35

IFNg

Answer 35

Chronic granulomatous disease

Question 36

il-2 as a cytokine therapy, use?

Answer 36

RCC

Question 37

Which CART therapy is most commonly used and which malignancies is it successful against?

Answer 37

CD19-CART cell, successful against CD19 B cell malignancies

Question 38

Antibody specific for CTLA4

Answer 38

Ipilimumab (checkpoint blockade thus increased T cella ctivity)

Question 39

Antigens bound to CD28

Answer 39

CD80/86 (B7) (stimulatory)

Question 40

ctla-4 ANTIGENS

Answer 40

CD80/86 (B7) (inhibitory)

Question 41

Which cells is PD-1 found on?

Answer 41

Tregs

Question 42

Which cells are PD-L1 and PD-L2 found?

Answer 42

APC and some tumours i.e. can activate PD-1 which is inhibitory --> inactivates the T cells

Question 43

Drugs targeting PD-1

Answer 43

Pembrolizumab and nivolumab

Question 44

Which malignancies are CTLA-4 and PD-1 monoclonals successful against?

Answer 44

Melanoma

Question 45

SE of chekcpoint inhibitors

Answer 45

Autoimmunity