3 Innate Immune System

Question 1

What is the immune system?

Answer 1

Cells and organs that contribute to immune
defences against infectious and non-infectious
conditions (self vs non-self)

Question 2

When is a pathogen infectious?

Answer 2

When it succeeds in evading the immune system or overwhelming the host’s immune defences

Question 3

What are the roles of the immune system?

Answer 3

Pathogen recognition
Containing and eliminating the infection
Regulating itself
Remembering pathogens

Question 4

List some aspects of innate immunity?

Answer 4

Fast
No specificity
Lack of memory
No change in intensity

Question 5

What are the different barriers?

Answer 5

Physical barriers
Physiological barriers
Chemical barriers
Biological barriers

Question 6

What are different physical barriers?

Answer 6

Skin
Mucous membranes
Bronchial cillia

Question 7

What are the physiological barriers?

Answer 7

Diarrhoea
Vomiting
Coughing
Sneezing

Question 8

What are the chemical barriers?

Answer 8

Low Ph

Antimicrobial molecules

Question 9

Name some antimicrobial molecules

Answer 9

IgA
Lysozyme 
Mucus 
Beta defensins 
Gastric acid

Question 10

What areas of the body are kept at low pH?

Answer 10

Skin
Stomach
Vag

Question 11

What is the role of the normal flora in innate immunity?

Answer 11

Competes for attachment sites and resources and produces antimicrobial chemicals

Question 12

What molecules do we get from the flora?

Answer 12

Vitamin K
B12
B vitamins

Question 13

What are some ways that the skin is breached?

Answer 13

Skin loss
Surgery
Injection
IV lines

Question 14

What sort of person is predisposed to flora overgrowth?

Answer 14

Immuno-compromised

Question 15

What are the main phagocytes?

Answer 15

Macrophages
Monocytes
Neutrophils

Question 16

What happens to neutrophil number during infection?

Answer 16

Increases

Question 17

What cells defends agaisnt multi cellular parasites?

Answer 17

Eosinophils

Question 18

What cells are early actors in inflammation?

Answer 18

Basophils and mast cells

Question 19

What PAMP detects LPS?

Answer 19

TLR4

Question 20

What PAMP detects peptidoglycan?

Answer 20

TLR2

Question 21

What PAMP detects flagellin?

Answer 21

TLR5

Question 22

What is oponisation?

Answer 22

Sugar coating, enhances attachment of phagocytes and clearance of microbes

Question 23

List some opsonins?

Answer 23

C3b
C4b
IgM
IgG
CRP
MBL

Question 24

State the phagocytosis pathway

Answer 24

…

Question 25

What happens in the oxygen dependent pathway?

Answer 25

Toxic O2 products for the pathogens - ROS species

Question 26

What are the oxygen independent pathways?

Answer 26

Lysozyme
Lactoferrin or transferrin
Cationic proteins
lytic and hydrolytic enzymes

Question 27

How is the complement pathway activated?

Answer 27

Antibodies

Alternative - cell surface constituents

MBL pathway -

Question 28

What complement proteins recruit phagocytes?

Answer 28

C3a and C5a

Question 29

What complement proteins causes opsonisation of pathogens?

Answer 29

C3b and C4b

Question 30

What complement proteins form the membrane attack complex?

Answer 30

C5 - C9

Question 31

What chemokines are released by macrophages?

Answer 31

Il-1
IL-6
TNF-a

Question 32

What the actions of the macrophages derived chemokines?

Answer 32

Increases acute phase proteins
- CRP and MBL

Tell the bone marrow to mobilize neutrophils

Cause inflammatory actions

Tell the hypothalmus to increase the body temperature