Final tidbits

Question 1

By how much are cells outnumbered by bacteria?

Answer 1

10:1

Question 2

2 types of surface defence enzymes?

Answer 2

• lysozyme (saliva, sweat, tears)
• pepsin (gut)

Question 3

What are the type 1 + 3 interferons?

Answer 3

alpha, beta, lambda

Question 4

What are 4 actions of type 1 and 3 interferons?

Answer 4

1. activates NK cells
2. upregulates MHC, Mx proteins
3. activates RNase L, PKR
4. induces anti-viral state

Question 5

What is the key type 2 interferon?

Answer 5

IFN-gamma

Question 6

What are 3 actions of IFN-gamma?

Answer 6

1. proinflammatory
2. Th1 cytokine
3. immune interferon

Question 7

Which cells are an important early source of cytokines?

Answer 7

NK cells

Question 8

Which cells are an important early source of cytokines?

Answer 8

NK cells

Question 9

What are 4 key roles of antibodies?

Answer 9

1. neutralisation
2. opsonisation
3. complement activation
4. may trigger cell-mediated cytotoxicity (ADCC)

Question 10

What are 4 strategies of viruses to evade the immune response?

Answer 10

1. block IFN induction
2. decoy IFN receptors
3. perturbation of IFN signalling
4. downregulate ISGs - IFN-stimulated genes

Question 11

What is the key chemokine that attracts neutrophils?

Answer 11

IL-8

Question 12

Which chemokines do eosinophils respond to?

Answer 12

eotaxin, RANTES

Question 13

What is a key role of IFN-gamma?

Answer 13

released by T cells to enhance activation of macrophages

Question 14

What may be the effects of TNF-alpha?

Answer 14

fever and weight loss, systemic effects associated with infection

Question 15

What stops NK cells from becoming active?

Answer 15

MHC I complexes

Question 16

What is meant by neutralisation of a pathogen e.g. as performed by antibodies?

Answer 16

block surface receptors, prevent it from attaching to or infecting host cells

Question 17

What is the form of antigen which is recognised by T cells?

Answer 17

sequences of peptide from digested antigens presented by APCs (NOT molecule surface/shape/charge)

Question 18

Which T cells recognise peptide presented by MHC II?

Answer 18

CD4 i.e. T helper cells

Question 19

Which cytokines are released by Th1?

Answer 19

IFN-gamma, TNF

Question 20

Which cytokines are released by Th2?

Answer 20

IL-5, IL-4, IL-9 and IL-13

Question 21

Which cytokine is released by Th17?

Answer 21

IL-17

Question 22

What are acute phase proteins defences against, bacteria or viruses?

Answer 22

bacteria - opsonins, bind in nons-specific way to bacteria