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Flashcards in Response To Pathogens Deck (18)
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1
Q

What are the essential functions of the innate immune system?

A

Initial rapid response to microbes
Elimination of damaged cells and initiation of tissue repair
Stimulation of adaptive immune system

2
Q

What is used by the innate immune system to recognise non-self?

A

Pattern recognition receptors (PRRs) on host cells recognise Pathogen associated Molecular Patterns (PAMPs) on pathogen

3
Q

Why are PAMPs suited to being recognised by the innate immune system?

A

1) conserved among classes of micro organisms
2) products of micro organisms that differ from humans
3) essential roles in structure or function of the microbe

4
Q

What are the types of PAMPs?

A

Bacterial PAMPs often components of cell wall; lipopolysaccharides, peptidoglycan, lipoteichoic acids and cell
wall lipoproteins
β glucan for fungal
Viral nucleic acids

5
Q

What are the three main types of PRR?

A

Signalling : toll-like, nod-like and RIG-like
Secreted
Endocytic

6
Q

Where are Toll-like receptors found?

A

Location reflects their ligand:
TLR that recognises extracellular are on cell surface
TLR that recognises intracellular are in the endosome

7
Q

What is the effect of TLR signalling?

A

Inflammation

8
Q

What are some deficiencies of TLRs?

A

MyD88 deficiency
IRAK4 deficiency
NEMO deficiency
all are associated with severe infections

9
Q

Where are NOD like receptors found?

A

Intracellular soluble proteins

10
Q

What are the four families of NOD-like receptor?

What do they cause?

A

NRLA
NLRB
NLRC
NLRPs

Regulate activation of Caspase-1 and form part of the inflammasome

11
Q

What are RIG-like receptors?

A

Soluble intracellular receptors that recognise the dsRNA of viruses in the cytoplasm
RIG-1, MDA5 and LGP2

12
Q

What are the secreted PRRs?

A

Anti microbial peptides - α and β defensin
C reactive protein
Mannose binding lectin

13
Q

What are the endocytic PRRs?

A

Mannose receptors on macrophages and neutrophils

Scavenger receptors on macrophages

14
Q

What cells express PRRs?

A
Neutrophils
Monocytes
Macrophages and dendritic cells
B cells
Mast cells 
Some non-haematopoietic cells
15
Q

What are the vascular effects of pattern recognition?

Why do they happen?

A

Cytokines from dendritic cells and resident cells induce changes in endothelial cell vessel walls and allow infiltration of cells and plasma proteins to site of infection

Increased vascular diameter: heat and redness
Increased vascular permeability: swelling and pain

16
Q

What is chronic granulomatosus disease?

How is it diagnosed?

A

Characterised by repeat infections
Due to delayed neutrophil apoptosis and defective superoxide production. Mutations in components of superoxide complex

FBC showed neutropenia, CRP/ESR show inflammation and test oxidative function

17
Q

How is complement involved in an antibacterial response?

A

Classical pathway opsonises the pathogen for phagocytosis

Also forms membrane attach complex to make holes in the membrane

18
Q

How is synthesis of the acute phase proteins initiated?

A

Cytokines TNFα, IL-1β and IL-6 stimulate Hepatocytes to form them