Cell mediated immunity

Question 1

give an example of an intracellular pathogen ?

Answer 1

viruses and bacteria

Question 2

give examples of extracellular pathogens ?

Answer 2

ectoparasites such as lice and some bacteria

Question 3

what type of pathogen size wise is a virus ?

Answer 3

a microscopic one

Question 4

is a protozoan parasite a unicellular or multicellular ?

Answer 4

unicellular

Question 5

is a tapeworm multicellular or unicellular ?

Answer 5

multicellular

Question 6

what does it depend on in a pathogen on what immune response is given ?

Answer 6

the size of the pathogen

Question 7

what cannot be done if the pathogen is too large ?

Answer 7

it cannot be phagocytosed whole

Question 8

what is a cell mediated response ?

Answer 8

an immune response that involves cells

Question 9

what do the resident cells at the site of entry do ?

Answer 9

they recruit innate cells to the site

Question 10

what type of cells are involved in a cell mediated response ?

Answer 10

innate and specific cells

Question 11

what are the effector responses ?

Answer 11

this is when a response to do something occurs such as for phagocytosis to occur

Question 12

an effector response is the antibody based agglutination , what does this mean ?

Answer 12

it is the clumping of particles

Question 13

describe the antibody mediated cytotoxicity ?

Answer 13

mechanism of cell-mediated immune defense whereby an effector cell of the immune system actively lyses a target cell, whose membrane-surface antigens have been bound by specific antibodies.

Question 14

list the innate cells involved in cell mediated immunity ?

Answer 14

Nk cells
basophils
granuloytes
mast cells

Question 15

what are the specific cells involved in cell mediated immunity ?

Answer 15

the direct effect cytotoxic T cells

antibodies

Question 16

how does recognition occur in innate cells ?

Answer 16

the pathogen associated molecular pathways (PAMP’s) bind with the pattern recognition receptors (PRR’s)

Question 17

how does the specific B and T cells go through recognition ?

Answer 17

the specific amino acid sequence of proteins results in antigen - antibody binding and T cell receptor binding.

Question 18

if the site of an extracellular infection is in the interstitial spaces , blood or lymph how is protection achieved from a pathogen ?

Answer 18

by complement
phagocytosis
antibodies

Question 19

if the site of an extracellular infection is the epithelial surface how is protection against the pathogen achieved from say gnorrhoeae?

Answer 19

antimicrobial peptides

antibodies especially IgA

Question 20

if there is an intracellular infection in the cytoplasmic cells of say a virus how is the protective response ?

Answer 20

NK cells

cytotoxic T cells

Question 21

if the intracellular infection is in the vesicular cells of say leishmania then how is this fought ?

Answer 21

by using T cells and NK cells

macrophage activation

Question 22

how does blood clotting help in fighting a pathogen ?

Answer 22

it limits the spread

Question 23

in terms of time what is the difference between specific cells and non specific cells ?

Answer 23

specific cells take time to be produced while the non specific cells can respond first to try and control the infection

Question 24

an effector cell is Th1 for intracellular immunity , what do these do ?

Answer 24

they eliminate intracellular pathogens by activating macrophages through secreting IFN gamma.

Question 25

An effector cell is the Th2 for extracellular immunity to a pathogen , what do these do ?

Answer 25

they recruit eosinophils and basophils to eliminate and try to eradicate the pathogen

Question 26

whats the cells 3 cells that carry out phagocytosis ?

Answer 26

macrophages and neutrophils and dendritic

Question 27

what is produced when respiratory burst occurs ?

Answer 27

superoxide

Question 28

1st stage of phagocytosis ?

Answer 28

the cells has arms called pseudopod that surround the pathogen

Question 29

2nd stage ?

Answer 29

the lysosome then fuses with the phagosome to form a phagolysosome and the enzymes from the lysosome digest the pathogen.

Question 30

what are the toxic products called that can be produced ?

Answer 30

nitric oxide | hydrogen peroxide

Question 31

how can the rate of phagocytosis be increased ?

Answer 31

by the antibodies labelling the cell called opsonisation

Question 32

how is the waste excreted ?

Answer 32

by exocytosis

Question 33

what do our own cells contain ?

Answer 33

MHC

Question 34

list some granuolyctes ?

Answer 34

``` basophils neutrophils eosinophils NK mast cells ```

Question 35

what does a granulocyte contain ?

Answer 35

granules that contain toxic products

Question 36

what occurs when recognition occurs in the granulocytes by the receptors ?

Answer 36

the toxic products are released from the granules.

Question 37

what is the function of cytotoxic cells?

Answer 37

Cytotoxic cells are used to lyse body’s own cells – get rid of abnormal cells or pathogen infected cells

Question 38

does the pathogen contain MHC ?

Answer 38

nope only the bodies own cells

Question 39

how does the cytotoxic cells recognise the bodies own cells ?

Answer 39

by the MHC

Question 40

do the cytotoxic T cell lyse the pathogen directly ?

Answer 40

no

Question 41

is CD8+ a cytotoxic T cell ?

Answer 41

yes

Question 42

what is recognition in a cytotoxic T cell dependent on ?

Answer 42

the amount of MHC expressed

Question 43

what type of ligand does a cytotoxic T cell contain ?

Answer 43

a FAS ligand which has interaction with the target cell

Question 44

what is an immunological synapse ?

Answer 44

this is what allows the cells to be in close contact and granules pass through

Question 45

what does perforin and granzymes do ?

Answer 45

they induce apoptosis

Question 46

does inflammation occur when apoptosis happens and is this good or bad ?

Answer 46

no inflammation which is good as this means no healthy tissue is damaged

Question 47

perforin is found in granule of cytotoxic T cell , role ?

Answer 47

aids in delivering contents of granules into cytoplasm of target cell

Question 48

granzymes found in granules of cytotoxic , role ?

Answer 48

these are serine proteases that activate apoptosis once in the cytoplasm of target cell

Question 49

granulsin is found in granules of cytotoxc T cell , role ?

Answer 49

it has antimicrobial actions and can induce apoptosis

Question 50

what does the rapid delivery of granules result in ?

Answer 50

polarisation of the granules before exocytosis occurs

Question 51

when the death signal is released and this causes a cell to die , what occurs ?

Answer 51

a caspase cascade occurs

Question 52

are granules released before or after the target cell is stimulated or direct death signal ?

Answer 52

after

Question 53

do the T cells just kill one cell?

Answer 53

no they go on to kill the next target cell as they are serial killers

Question 54

do NK cells have one type of receptor or more?

Answer 54

they have 3 types

Question 55

what's the 2 responses of a NK cell ?

Answer 55

it can either activate killing by inducing apoptosis or it inhibits killing

Question 56

what does interferon gamma activate ?

Answer 56

macrophages

Question 57

helper T H2 cells explained ?

Answer 57

activated by IL4 IL-5 IL 10 and causes recruitement of eosinophils and basophils and cause antibody production as B cells activated.

Question 58

TH17 explained ?

Answer 58

activated by Il-17A and involved in antibody prodcution

Question 59

what is a granuloma and cyst ?

Answer 59

These are cells that can form organized structures – granulomas or tissue cysts . They seal off the pathogen and this starves it of nutrients and oxygen which can cause damage at the site of infection