Innate Immunity II

Question 1

What do macrophages and DCs do?

Answer 1

Uptake and degragate

Question 2

How does uptake and degradation occur?

Answer 2

Macrophages and DCs

Question 3

Phagocytosis step by step

Answer 3

Actin is part of cells exoskeleton
Psuedopodia surround particle
Vacoule forms
Matures into phagosome
pH drops allowing enzymes to work

Question 4

Killing mechanism of macrophages and DCs

Answer 4

Proteolytic/hydrolytic enzyme.
Reaction O/N species
Antimicrobial peptides
Nutrient deprivation (passive)

Question 5

Examples of reaction oxygen species

Answer 5

NAPH-oxidase generates superoxides and hydrogen peroxide.

Question 6

Example of reaction N species

Answer 6

Nitric oxide synthases produces NO + others.

Question 7

Examples of antmicrobial peptides

Answer 7

Cathelicidins
Bacteridial increasing protein

Question 8

What does BPI do?

Answer 8

Bactericidal increasing protein forms pores in bacterial membranes

Question 9

What are the four outcomes of phagocytosis by macrophages and dendritic cells. KPRP

Answer 9

Killing
Presentation - activating T cells
Removing apoptopic cells
Producing cytokines and inflammatory molecules

Question 10

What are the two phages of innate immune response to infection

Answer 10

Steady state
Inflammatory phase

Question 11

Define inflammation

Answer 11

General term for accumulation of fluid, plasma proteins and leukocuytes initiated by physical trauma, infection or local immune response.

Question 12

Medical: Less than 6 weeks

Answer 12

Acute

Question 13

Medical: More than 6 weeks

Answer 13

Chronic

Question 14

What are the clinical signs of inflammation

Answer 14

Swelling
Heat
Pain
Redness
Loss of function

Question 15

What are the 3 stages of inflammation? IRR

Answer 15

Initiation
Recruitment of effector cells (mainly neutrophils)
Resolution (switching off/removing cells)

Question 16

Edema definition

Answer 16

Swelling

Question 17

Neutrophil time line during swelling

Answer 17

Neutrophils are recruited, then die and are ingested by monocytes/macrophages to remove them.

Question 18

Neuropenia definition

Answer 18

Low number of neutrophils

Question 19

What does severe congenital neutropenia lead to?

Answer 19

Death in infancy due to severe infections

Question 20

What can chemotherapy induced neutropenia lead to?

Answer 20

Infection and or feath

Question 21

AML

Answer 21

Acute myeloid leukamiea

Question 22

Why does AML cause neutrophilia?

Answer 22

Immunocompromisation due to immature myeloid cells.

Question 23

Neutrophilia

Answer 23

Too many neutrophils

Question 24

Why is neutrophilia bad?

Answer 24

Immature cells are non-functional

Question 25

Initiation of inflammation:

Answer 25

Bacterial uptake by macrophages and mast cell degranulation. Increased vessel permeability, increase in soluble components from blood, abs and complement. Chemokines and bacterial products faciliate chemotaxis.

Question 26

What do inflammatory cytokines regulate>

Answer 26

Adhesion molecules on the endothelium and neutrophils allowing recruitment of cells from blood.

Question 27

Main stages of leukocyte recruitment.

Answer 27

Rolling Activation by cytokines Firm adhesion Extravasation (Diapedesis)

Question 28

Diapedesis

Answer 28

Is where the WBC squeezes through the endothelial cell reaching the basement membrane

Question 29

Example of proinflammatory cytokine

Answer 29

TNF-alpha

Question 30

Where and how are neutrophils kileld>

Answer 30

At site of inflammation, the neutrophils are activated by PAMPs to unload their weapons.

Question 31

Neutrophils deliver many anti-microbial molecules

Answer 31

Oxdative burst (NADPH), NO synthase and myeloperoxidase

Question 32

What does myeloperoxidase form?

Answer 32

Hypochlorous acid

Question 33

What does host tissue damage by neutrophils lead to>

Answer 33

Liquefication and pus formation

Question 34

Final suicide of neutrophil requires

Answer 34

IL-8

Question 35

How is inflammation resolved?

Answer 35

Active apoptosis of neutrophils.

Question 36

What cell type is a specialised granular lymphocyte?

Answer 36

NK

Question 37

What triggers NK's antibody-dependent cellular toxicity (ADCC)

Answer 37

Recognition of Ab coated cells triggers killing

Question 38

How to NK cells kill

Answer 38

Perforin and granzyme B