Immunity Against Infection I

Question 1

Give an example of a bacteria which is ec and depends on epithelial cell binding

Answer 1

Streptococcus

Question 2

Which epithelial surface bacteria causes gonorrhoea and meningitis

Answer 2

Neisseria

Question 3

Which fungi causes oral candidiasis

Answer 3

Candida albicans (oral thrush)

Question 4

Name a few parasites

Answer 4

Trypanosoma

Worms

Protozoa

Question 5

What does different effector response depend on

Answer 5

Localisation of pathogen (EC or ic)

Stage of infection

Question 6

Which 2 areas can viruses be seen

Answer 6

EC in fluid like blood - at early stage of infection

Or

Cytoplasmic intracellular

Question 7

Give 2 examples of intracellular pathogens that live vesicular eg in macrophages

Answer 7

Leishmania and mycobacterium

Question 8

Can Protozoa be ic and EC

Answer 8

Yes

Question 9

Which responses are important for extracellular pathogens like candida,streptococcus, viruses in early stages

Answer 9

Antibodies , complement, phagocytosis, epithelial adhesion block by iga, amps

Question 10

Where are amps made for extracellular protection

Answer 10

Epithelial cells

Question 11

What responses are for ic cytoplasmic pathogens (viruses or Protozoa)

Answer 11

CD8 cells, NK cells

Question 12

Which responses needed for vesicular intracellular pathogens like leishmania and mycobacterium

Answer 12

T cell/NK cell macrophage activation

Question 13

are NK cells part of innate along with barriers , amps and complement

Answer 13

Yes

Question 14

What type of pathogen needs th1 response and why

Answer 14

Vesicular pathogens - for macrophage activation

Cytoplasmic - for NK and CD8 activation

Question 15

What type of pathogen is th2 for

Answer 15

Extracellular, stimulates eosinophils granule release, mast cells histamine, antibody igE switching

Question 16

Why are th17 for extracellular pathogens/fungi like candida

Answer 16

Il17 causes chemotaxis of important cells like neutrophils and other inflammatory cells

Question 17

Which types of bacteria have thick peptidoglycan wall

Answer 17

Gram positive like streptococcus and staphylococcus

Question 18

How many types of TLR are there which stimulate innate response

Answer 18

10

Question 19

Which prr are intracellular

Answer 19

Nod like receptors

Question 20

Where are tlr located

Answer 20

On vesicles inside cells (for ic killing) or on cell surface (EC killing)

Question 21

What do Tlr do

Answer 21

Induce inflammation
Mature dendrites via danger signal (upregulate B7 and MHC)
Induce differentiation of T cells by determining cytokine release of apc

B cell ti 1 activation

Question 22

Can bacteria be ic and EC

Answer 22

Yes.

Mycobacterium are vesicular ic

Strep and neisseria on cell surface

Question 23

What protects bacteria from phagocytosis

Answer 23

Capsule

Question 24

What does streptococcus EC bacteria cause

Answer 24

Pneumonia and meningitis

Question 25

What does vaccine for strep include

Answer 25

23 diff polysaccharides strep has to produce diff antibodies specific for them

Question 26

Which vaccine for strep helps a TD response by B cells

Answer 26

Conjugate vaccines (for children under 2 don’t recognise the ti2 ag on strep)

Question 27

Which bacteria are killed by Mac in complement which is activated by antibodies igm and igG

Answer 27

Gram -ve like neisseria

Question 28

What is importance of antibodies in EC bacteria protection eg strep or neisseria

Answer 28

Opsonisation via fc receptors Activation of complement and c3b opsonisation Neutralise toxins eg tetanus Prevent epithelial adhesion via iga

Question 29

What are you susceptible to without complement / if you have genetic defect in eg c3b or Mac

Answer 29

Neisseria gonorrhoea (EC cell surface, killed by Mac because gram -ve)

Question 30

When are bacteria most vulnerable to complement lysis

Answer 30

When dividing

Question 31

How do mycobacterium tb survive phagocytosis

Answer 31

Survive in macrophages (ic bacteria) Prevent phagosome fusion with lysosome

Question 32

Although th1 are mostly important in ic pathogens. How are they important for EC too

Answer 32

Activate macrophages via ifny and cd40L signal | Better at antigen presenting eg to stimulate th2 response and also release cytokines

Question 33

What does mycobacterium leprae cause (IC)

Answer 33

Tuberculoid leprosy and lepromatous leprosy

Question 34

Why is tuberculoid leprosy slower in progression and low infect ivory

Answer 34

Th1 response Allows activation of macrophages, NK and CD8 cells to kill mycobacterium intracellular

Question 35

why is lepromatous leprosy not effective in response

Answer 35

Th2 response. More ab and not effective for ic pathogens like mycobacterium Low T cell responses

Question 36

What forms when th1 macrophages aren’t killing mycobacterium fast enough and they aggregate

Answer 36

Granulomas - necrotic area where infection isn’t cleared fast enough

Question 37

Do mycobacterium leprae stay alive in macrophages in lepromatous leprocy

Answer 37

Yes. They are not being killed by antibodies because they aren’t effective for ic pathogens