Foreign activators

Question 1

what are foreign activators

Answer 1

non-self molecules (which originate outside the body), recognised by the immune system

Question 2

example of FAs

Answer 2

microbes, allergens, foreign tissue

Question 3

foreign activators are not

Answer 3

small like other chemical

- molecules with a size less than several thousand daltons are poorly recognised

Question 4

which type of FAs are recognised well

Answer 4

proteins and polysaccharides

Question 5

how does the immune system recognise FAs

Answer 5

receptors

Question 6

example of FA and receptor interactionn

Answer 6

APC initially comes into contact with FA- presenting it on its surface to a T ell, which produces cytokines

Question 7

cytokines work by

Answer 7

switching on other immune cels

making other cells more effective

signals to other parts of the immune system to signal in certain ways

Question 8

when the immune system fails

Answer 8

consequence of immune system not recognising FAs

Question 9

what if the immune system over responds to self or non self antigens

Answer 9

e.g. autoimmune diseases or sepsis

Question 10

when the immune system fails to respond

Answer 10

e.g. AIDs

Question 11

two arms of Immune system

Answer 11

innate

adaptive

Question 12

innate immunity

Answer 12

• epithelial barriers

- phagocytes, dendritic cells, complement, NK cells

Question 13

adaptive immuntity

Answer 13

• B cells- antibodies

- T cells - effector T cells

Question 14

I and A systems are

Answer 14

constantly talking to eachother

Question 15

in both arms of the immune system FAs are recognised by

Answer 15

receptors

Question 16

innate immune response occurs within

Answer 16

a few hours or days after exposure to FA

Question 17

examples of innate receptors

Answer 17

soluble receptors
- secreted from cells found in the blood, plasma, lymph, mucosal section
cell surface receptors
- found on macrophages neutrophils, lymphocytes ad other somatic cells

Question 18

innate receptors are

Answer 18

encoded in germline- limited diversity

- a finite list of antigens can be recognised

Question 19

innate receptors typically only

Answer 19

recognise structures common to different molecules e.g. LPS in gram neg bacteria

Question 20

Adaptive receptors are much

Answer 20

more powerful, focused and targeted

Question 21

Cell surface receptors of adaptive system

Answer 21

• T and B cells

-

Question 22

soluble receptors of adaptive

Answer 22

blood, plasma, lymph, mucosal secretions

Question 23

adaptive receptors typically

Answer 23

recognise structures unique to different molecules

Question 24

Innate receptors recognise

Answer 24

PAMPs- recognised to PRR

Question 25

although the innate system can only react to a certain number of common FAs

Answer 25

this enables it to act quickly

Question 26

examples of FAs which the innate can respond to

Answer 26

- cell wall components= peptidoglycan, lipopolysaccharide, phospholipomannans - nucleic acids e.g. viruses - flagellin - conserved stress proteins - -> NOT FOUND IN HUMANS

Question 27

examples innate soluble receptors

Answer 27

- natural antibodies - comlement - pentraxins - collectins - ficolins

Question 28

examples of innate cell receptors

Answer 28

TLR Nod-Like receptors Rig like receptors C Type lectin like receptors

Question 29

How is self recognition avoided

Answer 29

-innate system tends to recognised molecules which are never found in mammals e.g. lipopolysaccharide, phospholipomannans, peptidoglycan etc

Question 30

Toll like receptors structure

Answer 30

extracellular domain (ligand recognition) and intracellular domain (signalling)

Question 31

process of TLR activation

Answer 31

1) recognition of bacterial molecule by TLR (by horseshoe part) 2) dimerisation of the TLR 3) signalling and inflammatory response e.g. NF-kB

Question 32

if too many TLRs become activated

Answer 32

sepsis- one balancing act

Question 33

receptors are also involved in signalling betwen

Answer 33

cells of the immune system

Question 34

cytokines

Answer 34

chemical signals that reg the immune system

Question 35

sepsis

Answer 35

consequence of infection by microorganism, systemic overwhelming infection, causes coalition of blood- over production of signals) - positive feedback loop

Question 36

why was the Spanish flu so devastating and mainly affected 20/30 yr olds

Answer 36

due to their bodies having the strongest immune system- over reactive immune system and cytokines causing mortality

Question 37

example of experimental drug which was intended to activate T cells

Answer 37

TGN1412- an antibody ro CD28 on T cells. - when it reached human trials many people became unwell even at 500 the concentration - had been tolerated well by the weaker immune system of animals

Question 38

an adaptive receptors recognise..

Answer 38

antigens that are unique to an individuals pathogen | - takes time to develop and mature but can provide a vy powerful protective response

Question 39

antibodies

Answer 39

soluble receptors of adaptive immune system

Question 40

most common types of proteins recognised by adaptive immune system

Answer 40

proteins and polysaccharides

Question 41

the adaptive immune system has ...... than the innate

Answer 41

less of a requirement for a panel of diff receptors

Question 42

types of adaptive soluble receptors

Answer 42

natural antibodies, compliment, pentraxins, collecting, folicins

Question 43

where does the myriad of antibodies each specific for a diff epitope come from?

Answer 43

- b- cell possesses gene for one antibody type that recognises one epitope

Question 44

diff antibodies recognise

Answer 44

diff epitopes

Question 45

different antibodies are produced via

Answer 45

random recombination of germ cells

Question 46

antibodies are the most important

Answer 46

soluble receptorefector

Question 47

how is self-recognition avodided

Answer 47

-clonal deletion eliminates self-recognition by the adaptive response

Question 48

where do B cells mature

Answer 48

bone marrow

Question 49

how does clonal deletion ensure self-recognition is avoided

Answer 49

bone marrows mature in the bone marrow, where self antigens are present - B cells which produce antibodies against these antigens (epitopes) are deleted

Question 50

adaptive system receptors have potentially

Answer 50

infinite adaptability to recognise discrete features