2 - foreign activators Flashcards

1
Q

‘non-self’

A

substance that originates from outside the body at birth

generally bug e..g polymer (>3000 daltons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

examples of non-self molecules

A

microbes
allergens
foreign tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

tyes of immune failure

A

non-responsiveness

over-responsiveness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

examples of non-responsiveness of immune system

A

HIV

tumours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

examples of over-responsiveness of immune system

A

sepsis

auto-immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

features of innate immune system

A

fast
general
hours after exposure to infectious agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

features of adaptive immune system

A

specific
powerful
delayed - days after exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

soluble receptors secreted from

A

cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

soluble receptors found in

A

blood
plasma
lymph
mucosal secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

cell surface receptos found on

A

macrophages, neutrophils, lymphocytes and other somatic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

properties of innate receptors

A

encoded in germline
pre-coded to recognise foreign activators
finite number - limited diversity
recognise structures common to different microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

properties of adaptive receptors

A

take time to evolve
generated by gene recombination
massive diversity
recognise structures unique to different microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

specific examples of immune system failure

A

spanish flu - 1918

TGN1412 - withdrawn 2006

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

spanish flu

A

1918-1920
most lethal flu outbreak ever recorded
20-40 million killed
20-30 year old heavily targeted (good immune systems)
over-activation of immune system led to increased production of cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

TGN1412

A

drug
a mono-clonal antibody to CD28 on T cells
passed animal testing
clinical trials - intended to only mildy activate immune system
caused cytokine storms and organ failure in humans
withdrawn from development in 2006

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

types of PAMPs

A

cell wall components
nucleic acid
conserved surface proteins
conserved stress proteins

17
Q

examples of cell wall components - PAMPs

A

bacteria:

  • peptidoglycan
  • LPS

fungi:
- phospholipomannans

18
Q

examples of nucleic acid -PAMPs

A

bacteria:
- CpG motif DNA

viruses:

  • ssRNA
  • Ds RNA
19
Q

example of conserved surface proteins - PAMPs

A

bacteria:

- flagellin

20
Q

examples of conserved stress proteins

A

bacteria:

- heat shock proteins

21
Q

PPRs

soluble receptor examples

A
natural antibodies
complement
pentraxins
collectins
ficolins
22
Q

PRRs

cell receptors examples

A
TLRs
NOD-like receptors
RIG-like receptors
C-type lectin-like receptors
scavenger receptors
N-formyl met-leu-phe receptors
23
Q

Toll-like receptors - structure

A

extracelllular domain - horseshoe structure, important for recognition

intracellular domain - dimerisation of 2 domains essential for signallign

24
Q

examples of homodimer TLRs

A

TLR9 - recognises CpG DNA

TLR5 - recognises flagellin

25
Q

example of heterodimer TLR

what does it recognise

A

TLR7/8 - recognises ssRNA

26
Q

what happens if there are too many TLRs

A

increased cytokine production
increased production of TRanscription factors
inflammatory cascde

27
Q

describe TLR4 binding and signalling

A

TLR4 allows macrophage to recognise LPS
LPS binding protein transports LPS to CD14
CD14 transports LPS to the TLR
LPS detected by MD-2
TLR dimerisation
signalling pathway initiated eg. NF-kappaB

28
Q

LPS binding protein

A

accessory protein

transports LPS to CD14 receptor

29
Q

CD14

A

cluster of differentiation gene receptor

either soluble
OR
binds to cell-surface via glycosylphatidylinositol anchor

transports LPS to TLR

30
Q

MD-2

A

recognises LPS

forms complex with TLR4

31
Q

what do antibodies recognise

A

recognise discrete epitopes on a protein antigen

32
Q

antibdy recognition sites

A

at tips
can evolve and change to recognise different molecules
CDR

33
Q

CDR

A

complementarity determining region
part of variable chain of an antibody
hyper-variable
determine specific binding of the antibody

34
Q

epsilon toxin

A

important in disease in lambs and livestock

- all now vaccinated against

35
Q

antibodies and gene recombinaton

A

lots of antibodies produced by different genes

each has different specificty

36
Q

where does b cell production occur

A

progenitor cells in bone marrow

37
Q

clonal deletion

A

the process by which self-recognising b cells are eliminated in the bone marrow

38
Q

Product of clonal deletion

A

only B cells that recognise foreign antigens are allowed to mature and produce antibodies