Innate Immunity

Question 1

What is innate immunity

Answer 1

First line of defence

Question 2

What are some innate immune mechanisms in the oral cavity

Answer 2

• barrier functions
• saliva
• initiation of innate immunity
• recognition of threats
• signalling pathways
• cytokines and chemokines

Question 3

Is innate immunity specific or non specific

Answer 3

Non specific

Question 4

How does the immune system initially respond to a threat

Answer 4

Tissue Homestasis, a balance of healthy and unhealthy bacteria

Question 5

What are commensal organisms

Answer 5

They inhabit everyone’s oral cavity, the immune system needs to respond to these to have a low immune response to prevent infection

Question 6

After what period of time would an innate immune response occur

Answer 6

After about 4 days

Question 7

What is the innate immune system

Answer 7

The first line of defence

Question 8

What does the epithelium of the innate immune response produce

Answer 8

Produces Antimicrobial peptides
Produces cytokines/chemokines

Question 9

What are non professional immune cells

Answer 9

Epithelial/endothelial cells + fibroblasts

Question 10

What are the innate cell subsets and complement

Answer 10

• phagocytic cells (macrophages, neutrophils)
• antigen-presenting cells (dendritic cells)

Main role is phagocytosis

Question 11

What is the function of a chemokines

Answer 11

Cell recruitment

Question 12

What is the function of cytokines

Answer 12

Cell activation/proliferation

Question 13

What is the role of the epithelium in the oral cavity

Answer 13

Physical barrier, produces different compounds such as Antimicrobial peptides, Immunoglobins, Lactoferrin, lysozyme and cystatins

Epithelium provides structural/mechanical support

Question 14

What are Antimicrobial peptides

Answer 14

Small (<50 amino acids)
They are host defence peptides and they are effective in low concentrations

Question 15

What are some examples of Antimicrobial peptides

Answer 15

• beta defensins
• human neutrophil peptides
• cathelicidins
• psoriasin proteins

Question 16

What is the role of Antimicrobial peptides

Answer 16

• directly kill microbes (bacterial lysis)
• modulates host immunity (recruits immunocytes ect)

Question 17

What is secretory immunoglobulin A

Answer 17

Secretory piece will absorb to the saliva forming a protective layer

Question 18

What is the main role of secretory immunoglobulin A

Answer 18

Attaches to and neutralises microbes

Question 19

What is lactoferrin

Answer 19

Transport iron ions but has an Antimicrobial activity, present in saliva and produced by neutrophils

Question 20

What is lyzosome

Answer 20

Present in saliva amd produced by macrophages/neutrophils, target cell walls of bacteria

Question 21

What are cystatins

Answer 21

Anti protease activity and supports remineralisation of the teeth

Question 22

What are antigens

Answer 22

Cells involved in immune responses that have receptors for components of micro organisms

Question 23

What is a toll like receptor

Answer 23

They can be present on the plasma membrane of the cell and there are different types on the surface and inside the cell, they recognise bacterial and fungal components on the plasma membrane and internalised toll like receptors recognise internalised viruses and internalised bacteria

Question 24

What are the two main toll like receptor

Answer 24

TLR 2 and TLR 4 they recognise a lot of bacteria and fungi

Question 25

What do dectin and glucan receptors recognise

Answer 25

Fungal recognition

Question 26

What do NOD like receptors recognise

Answer 26

Bacterial recognition

Question 27

What do protease activated receptors (PARs) recognise

Answer 27

Microbial and allergen recognition

Question 28

What are the main roles of PRM receptors

Answer 28

Promote phagocytosis of microbes and promote activation of immune cells

Question 29

What is the importance of cytokines

Answer 29

They instruct a target cell what to do, they are important in T cell differentiation

Question 30

What are cytokines

Answer 30

Small proteins (<80kDa in size) Signalling molecules that coordinate an immune response

Question 31

What is an autocrine function of a cytokine

Answer 31

Alter behaviour of the cell from which they were secreted

Question 32

What is a paracrine function of cytokines

Answer 32

Alter behaviour of neighbouring cells

Question 33

What does the endocrine function of cytokines do

Answer 33

Enter circulation and alter behaviour of distant cells

Question 34

What does PRR stand for

Answer 34

Pattern Recognition Receptors (recognise antigens)

Question 35

What do cytokines and chemokines do in terms of receptor signalling

Answer 35

Shapes the type of the immune response

Question 36

What are chemokines

Answer 36

Small signalling molecules important in signalling and predominantly involved in cell recruitment

Question 37

What is the difference between cytokines and chemokines

Answer 37

Cytokines tell the immune cells what to do, chemokines tell the immune cells where to go

Question 38

What are the 4 classes of chemokines

Answer 38

- C chemokines (2 members) - CC chemokines (31 members) - CXC chemokines (18 members) - CX3C chemokines (1 member)

Question 39

What is the role of bradykinin

Answer 39

Important role in regulating blood pressure