Lecture 1

Question 1

Examples of anatomic barriers in innate immunity

Answer 1

Skin, oral mucosa, respiratory epithelium, intestine

Question 2

Examples of sensor cells

Answer 2

Macrophages, neutrophils, DCs

Question 3

Examples of inflammatory inducers

Answer 3

LPS, ATP, urate crystals

Question 4

Bacteria trigger macrophages to release…

Answer 4

cytokines and chemokines

Question 5

What causes redness, heat and swelling at infection site?

Answer 5

Vasodilation and increased vascular permeability, leading to migration of inflammatory cells into the tissue

Question 6

Pluripotent hematopoietic stem cell gives rise to…

Answer 6

Common lymphoid progenitor cell or common myeloid progenitor cell

Question 7

Macrophage effector functions

Answer 7

• Phagocytosis/intracellular signalling
• Cytokine production
• Ag presentation

Question 8

Dendritic cell effector functions

Answer 8

• Ag processing and presentation to T cells
• Cytokine production/T cell polarisation

Question 9

What did Elie Metchnikoff discover?

Answer 9

Phagocytes (i.e. macrophages) and phagocytosis (innate)

Question 10

What contribution did Paul Ehrlich make to adaptive immunity?

Answer 10

That antibodies ‘see’ antigens specific to individual pathogen types

Question 11

What did Ralph Steinman discover?

Answer 11

The existence of DCs and their role in linking innate and adaptive immunity (DCs can phagocytose antigens AND cross-present to T cells)

Question 12

What 3 properties determine the immune response?

Answer 12

Tissue site, cellular location, type of pathogenic infection

Question 13

What innate immune cell is the first to respond to an infection?

Answer 13

Neutrophil

Question 14

Neutrophil effector functions

Answer 14

• Phagocytosis
• Degranulation/extracellular killing
• NET formation
• Cytokine production

Question 15

What innate immune cells are important for attacking parasites?

Answer 15

Eosinophils and basophils

Question 16

Neutrophils produce __ via activation of NOX2.

Answer 16

superoxide

Question 17

Neutrophil activity increases substantially in what inflammatory disease?

Answer 17

Ulcerative colitis

Question 18

What gives macrophages specificity in their ability to recognise and respond appropriately to pathogens?

Answer 18

The expression of different families of PRRs on their surface

Question 19

Role of TNF

Answer 19

• Activation of local endothelium
• Initiation of cytokine production
• Upregulation of adhesion molecules

Question 20

Role of IL-6

Answer 20

• Triggers production of acute phase proteins from liver
• Enhances B cell Ab production
• Induces T cell polarisation

Question 21

Role of IL-8

Answer 21

• Triggers neutrophil chemotaxis
• Promotes angiogenesis

Question 22

Role of IL-12

Answer 22

• Activation of NK cells
• Polarisation of T cells to T helper cells

Question 23

Phagocytosis process

Answer 23

Chemotaxis, adherence via PAMP recognition, cell activation via PRR, initiation of phagocytosis, phagosome formation, phagolysosome formation, bacterial killing & digestion, release of degradation products

Question 24

2 major mechanisms by which NK cells kill target cells

Answer 24

1. Release of lytic granules
2. Death receptor
   (in both cases, target cells dies via apoptosis following release of caspases)

Question 25

Examples of DAMPs

Answer 25

IL-33, IL-1α, HMGB1

Question 26

Necrotic cells release __ , whereas apoptotic cells do not

Answer 26

DAMPs

Question 27

What can be released into the cell cytoplasm if the cell is perturbed/stressed, and what is the result of this?

Answer 27

Mitochondrial and nuclear dsDNA - act as danger signals and are sensed by cytoplasmic PRRs

Question 28

What type of receptors on phagocytes link microbe recognition with efficient intracellular killing?

Answer 28

G-protein coupled receptors

Question 29

TLR4 recognises LPS in association with which host accessory proteins?

Answer 29

MD-2 and CD14

Question 30

What transcription factors do TLRs activate to induce expression of inflammatory cytokines and type 1 IFNs?

Answer 30

NF-κβ, AP-1 and IRF

Question 31

Are NOD-like receptors intracellular or extracellular sensors?

Answer 31

intracellular

Question 32

What happens when RIG-I-like receptors detect cytoplasmic viral RNAs?

Answer 32

They activate MAVS to induce pro-inflammatory cytokine & type 1 IFN production

Question 33

Cytosolic DNA sensors signal through __ to induce type 1 IFN production

Answer 33

STING

Question 34

What activates the STING pathway?

Answer 34

cGAS

Question 35

Phagocytic receptors on macrophages that bind microbes and their components

Answer 35

Mannose receptor, complement receptor, lipid receptor (e.g. CD36), scavenger receptor (e.g. MARCO), Dectin-1 (β-glucan receptor), Fc receptor

Question 36

What GTPase do bacterial peptides activate to stimulate uptake of bacteria into phagosomes?

Answer 36

Rac2

Question 37

Rac2 induces assembly of a functional __ in the phagolysosome membrane to generate __

Answer 37

NADPH oxidase to generate superoxide