The Immune Response

Question 1

Following pathogen enrty, what does tissue resident cells bind to?

Answer 1

Pathogens

Question 2

What happens after tissue resident cells bind to pathogens?

Answer 2

Cell signalling and the release of proinflammatory mediatord and chemokines

Question 3

How do tissue resident macrophage recognise a pathogen?

Answer 3

Pattern recognition receptors (PRR) and macrophages bind to pathogen associated molecular patterns (PAMPs) on pathogens

Question 4

Where are pattern recognition receptors found?

Answer 4

On other innate immune cells

Question 5

What are the different cellular compartments are pattern recognition receptors found?

Answer 5

Cell surface for extracellular pathogens
Cytoplasmic for pathogens that have entered cells
Endosomal vesicles following cell entry

Question 6

What is the result of the binding pathogens to pattern recognition receptors?

Answer 6

Signalling and immune cell activation

Question 7

What does the binding of Toll-like receptors result in?

Answer 7

Gene transcription and the release of pro-inflammatory signalling molecules

Question 8

What is the earliest stage of inflammation?

Answer 8

Recognition of a pthogen by macrophages and dentric cells in tissues

Question 9

What gets afftected when soluble signalling molecules are released?

Answer 9

Local blood vessels

Question 10

What happend to the blood vessels when inflammation occurs?

Answer 10

The blood vessels dialate and express adhesion molecules which bind cells in the blood

Question 11

When tissue resident macrophages and dentric cells express new molecules, what is the role of the new molecules?

Answer 11

To start the adaptive response

Question 12

What is the result of cytokines released by tissue resident macrophage?

Answer 12

Changes to blood flow and permeability of vessel

Question 13

What increases movement of plasms proteins and leucocytes out of circulation?

Answer 13

Cytokines released by tissue resident macrophage

Question 14

What causes leucocyte influx into tissues?

Answer 14

Changes in blood flow and vascular permeability

Question 15

What are phagocytic cells?

Answer 15

Neutrophils and macrophages

Question 16

Movement into tissue cells is a multistep process helped by what?

Answer 16

cytokines, chemokines and adhesion molecules

Question 17

What are the two major families of adhesion molecules?

Answer 17

Integrins and selectins

Question 18

Where to leucocytes move once they have ‘stopped’?

Answer 18

Through the vessel wall through postcapillary venules

Question 19

What stimulates when chemokines act on the adhered leucocytes?

Answer 19

Their migration

Question 20

What and where do extravasated leucocytes follow?

Answer 20

Chemokine gradients to the site of infection

Question 21

What are endogenous?

Answer 21

Chemokines, complement fragments

Question 22

What are exogenous?

Answer 22

Bacterial products

Question 23

What happens in the first 6-24hrs of inflammation?

Answer 23

Accute inflammation, neutrophils predominate

Question 24

What replaces neutrophils after 24-48hrs?

Answer 24

Monocytes

Question 25

Why are neutrophils first?

Answer 25

They are most abundant leucocyte in blood
Rapidly respond to chemokines
Bind to adhesion molecules more tightly

Question 26

What is the lifespan of neutrophils?

Answer 26

24-48hrs

Question 27

Do monocytes live longer then neutrophiles?

Answer 27

Yes

Question 28

Do monocytes divide and dominate in prolonged inflammation?

Answer 28

Yes

Question 29

Why do we recriut cells to the dite of infection?

Answer 29

Pathogens at the dite of infection are recognised by phagotic cells recruited from the circulation
The recognition induces phagocytosis and intracellular killing
PRR’s on phagocytes bind to pathogen associated molecule patterns on bacteria

Question 30

What does phagocytosi require?

Answer 30

Recognition and binding
Engulfment
Killing

Question 31

What are the three steps of adaptive immunity?

Answer 31

1. Specialised peripheral lymphoid tissues concentrate antigens from portals of entry
2. Naive lymphocytes migrating through peripheral lymphoid tissues recognise antigens and intitate the adaptive response
3. Effector and memory lymphocytes circulating in the blood and home to peripheral sites

Question 32

What is the funtion of lymphocytes?

Answer 32

Can specifically recognise and ditinguish different antigenic determinants?

Question 33

What do lymphocytes consist of?

Answer 33

Distinctive subsets with different functions although they look the same

Question 34

What do B-lymphocytes produce?

Answer 34

Antibodies

Question 35

What to T-lymphocytes produce?

Answer 35

CD8+ or CD4+

Question 36

Do B and T cells have antigen receptors?

Answer 36

Yes BCR and TCR

Question 37

What are B and T cell antigen receptors generated by?

Answer 37

DNA recombination

Question 38

How are lymphocytes developed?

Answer 38

After birth, all blood cells, including lymphocytes are generated from stem cells in the bone marrow

Question 39

What happens when naive lymphocytes enter secondary lymphoid tissues and encounter entigen?

Answer 39

They become activated

Question 40

Is there a large or small population of naive lymphocyted that recognise a specific antigen?

Answer 40

A small population

Question 41

What does it mean for a naive lymphocytes to recognise a specific antigen?

Answer 41

Clonal selection

Question 42

what does activation of naive lymphocytes result in?

Answer 42

The proliferation and differentiation into armed effecot and memory cells

Question 43

Where do armed effectors migrate to?

Answer 43

The site of infection