What Is Immunity?

Front 1

are antibodies soluble?

Back 1

yes

Front 2

What is the type of disease when the immune response destructs self-tissue?

Back 2

autoimmune disease

Front 3

what is an antigen?

Back 3

any substance capable of triggering an immune response.

Front 4

Why are some transplanted tissues rejected as foreign?

Back 4

they acts as antigens.

Front 5

what level of immunity is confined to vertebrates?

Back 5

acquired immunity (adaptive immunity)

Front 6

what do T cells produce?

Back 6

cytokines

Front 7

what do B cells produce?

Back 7

antibodies

Front 8

where do the cells of the immune system come from?

Back 8

bone marrow

Front 9

Why can chicken pox kill you if you get it when you are older rather than when you are younger?

Back 9

cytokine storm - over-exxageration of immune response

Front 10

Why are smokers more prone to respiratory infections?

Back 10

thinning of mucus and reduction of ciliary hairs.

Front 11

name 2 physical barriers

Back 11

skin and mucous

Front 12

name 4 physiological factors

Back 12

acidity of stomach, normal gut flora, pH, temperature

Front 13

why is normal gut flora good?

Back 13

it prevents adhesion of other organisms

Front 14

how does the innate immunse system detect microbial components which are intrinsically foreign?

Back 14

pattern recognition recpetors

pathogen associated molecular patterns

Front 15

what cells express toll-like receptors?

Back 15

macrophages

Front 16

what is opsonisation?

Back 16

process of coating micro-organisms with plasma proteins to increase their adherence to phagocytic cells in preparation for phagocytosis.

Front 17

what is phagocytosis?

Back 17

ingestion and destruction by individual cells

Front 18

what does TLR2 recognise?

Back 18

peptidoglycan

Front 19

what does TLR4 recognise?

Back 19

lipopolysaccharide

Front 20

what does TLR5 recognise?

Back 20

flagellin

Front 21

What does TLR9 recognise?

Back 21

CpG, DNA

Front 22

what does activation of TLRs trigger?

Back 22

production of pro-inflammatory cytokines/chemokines which can also lead to the initiation of the adaptive immune response

Front 23

why is there often heat and redness?

Back 23

vasodilation - increased blood flow to tissues

Front 24

why is there often swelling?

Back 24

increased capillary permeability - increased fluid leakage into tissues

Front 25

what causes vasodilation?

Back 25

cytokines released by macrophages

Front 26

name 2 phagocytic cells

Back 26

macrophages, polymorphonuclear leucocytes (PMN)

Front 27

what is the acute phase response?

Back 27

innate body defence during acute illnesses - increased production of acute phase proteins by cytokines

Front 28

what produces the acute phase proteins?

Back 28

liver

Front 29

where are complement proteins found?

Back 29

in the blood

Front 30

what is the complement system?

Back 30

pro-enzyme to enzyme reactions forming an amplification cascade. small amount of amplification is required to generate a large response

Front 31

what is the membrane attack complex?

Back 31

punches holes in the bacterial cell wall.

complement activated, releases proteins, bacterium swells through uptake of fluid, bursts and is therefore killed

Front 32

what do nucleated cells produce in response to viral infection?

Back 32

type 1 interferons

Front 33

how are viruses detected? what recognises it?

Back 33

double stranded RNA not present in mammalian cells
TLR3

Front 34

what can recognise and destroy virally infected cells?

Back 34

natural killer cells

Front 35

what recognises antigens?

Back 35

lymphocytes

Front 36

what are the 2 types of lymphocytes that use a specific receptor to recognise an antigen?

Back 36

B cells and T cells

Front 37

where are antibodies found?

Back 37

blood and secretory fluids such as mucus

Front 38

what are antibodies collectively known as?

Back 38

immunoglobin (Ig)

Front 39

what are the 2 regions of an antibody?

What is the function of each?

Back 39

variable region - bind to antigen

constant region - opsonisation, activate complement, FcR mediated activity

Front 40

what are the 2 chains that antibodies are made of?

Back 40

light and heavy

Front 41

what are the 2 types of light chain?

Back 41

kappa, lambda.

one Ig molecules has either of these, NOT both

Front 42

what are the 5 different isotypes of heavy chain?

how are they distinguished?

Back 42

IgG, IgM, IgA, IgD, IgE

structure of the constant regions

Front 43

what is the effector function of IgG?

Back 43

neutralise toxins like tetanus, snake and scorpion venom by blocking their active site

binds with antigenic determinants on the virus coat including the region used by the virus for attachment to the target cell

Front 44

why is IgE important?

Back 44

large parasites like worms cannot be ingested by phagocytosis but when coated with IgE, Eosinophils can attack using IgE Fc receptors

Front 45

why is IgM a good agglutinator?

Back 45

due to its pentameric form.

Front 46

What is IgM good at?

What is it not so good at?

Back 46

complement fixing or complement activating

neutralising viruses or toxins

Front 47

why are immunoglobins and T cells considered to be structurally related?

Back 47

both have variable region that differ in amino acid sequence and both have a constant region

Front 48

what is another name for effector B cells?

Back 48

plasma cells

Front 49

what has to happen to the protein antigen before it is recognised by the t-cells?

Back 49

be processed into peptide and then be bound to MHC molecules

Front 50

what happens to T cells that recognise self-antigens?

Back 50

die by apoptosis

Front 51

what happens to T cells that recognise self-MHC molecules?

Back 51

continue to mature

Front 52

what is major histocompatability complex?

Back 52

cluster of genes on short arm of human chromosome 6

Front 53

what do proteins of the CD3 complex do?

Back 53

transmit signals into the T cell when the T cell receptor binds antigen

Front 54

whats the difference between MHC class 1 molecules and MHC class 2 molecules?

Back 54

Class 1 present peptide antigens derived from pathogens that replicate inside the cell like bacteria and viruses

class 2 present peptide antigens from pathogens that are present outside the cell taken by endocytotic vesicles

Front 55

where are MHC class1 expressed?

Back 55

on nucleated cells

Front 56

where are MHC class 2 expressed?

Back 56

antigen presenting cells like B cells, macrophages and dendritic cells

Front 57

what is the structure of MHC class 1?

Back 57

heavy chain or alpha chain. heavy chain has 3 extracellular domains - alpha 1 alpha 2 and alpha 3. binding site is formed by the folding of 1 and 2.

Front 58

what is the structure of MHC class 2?

Back 58

2 transmembrane chains - alpha and beta each contributes 1 domain to the binding site and 1 immunoglobin like supporting domain

Front 59

what are CD8 T-cells?

Back 59

recognise antigen in association with MHC class 1

Front 60

what are CD4 T cells?

Back 60

recognise antigen in association with MHC class 2

Front 61

why do MHC class I molecules present peptides only to CD8 T cells?

Back 61

The CD8 co-receptor binds the alpha3 domain of the MHC class heavy chain

Front 62

why do peptides bound to
MHC class II only stimulate CD4 T cells

Back 62

CD4 co-receptor binds to the beta 2 domain of the MHC class II molecules