Block 2 Lecture 4 -- Parasites

Question 1

What are types of parasites?

Answer 1

1) protozoa
2) helminths
3) ectoparasites

Question 2

Why are parasites problematic?

Answer 2

• • evoke weak innate immune response

- - mechanisms of evasion

Question 3

How do parasites resist the innate response?

Answer 3

1) some too large for phagocytosis
2) replicate and resist degradation within phagocytes
3) penetrate through skin

Question 4

How many species of leishmaniasis?

Answer 4

20

Question 5

What are the types of leishmaniasis?

Answer 5

1) cutaneous
2) mucocutaneous
3) visceral

Question 6

Characterize cutaneous leishmaniasis

Answer 6

bad - scars

Question 7

Characterize mucocutaneous leishmaniasis?

Answer 7

2nd worst form - ulcers

Question 8

Characterize visceral leishmaniasis

Answer 8

worst form - death

Question 9

What is the tx for leishmaniasis?

Answer 9

amboB/amBisome

Question 10

Th1 overactivation =

Answer 10

pro-inflammatory diseases

– T2DM, GVHD, arteriosclerosis

Question 11

Th2 overactivation =

Answer 11

anti-inflammatory Ab-mediated diseases

– infection, allergy, autoimmunity

Question 12

What is the signature cytokine of the Th1 response?

Answer 12

IFN-gamma

Question 13

What is the signature cytokines of the Th2 response?

Answer 13

IL-4

Question 14

What is classical macrophage activation?

Answer 14

enhanced killing induced by IFN-gamma

Question 15

What is alternative macrophage activation?

Answer 15

tissue repair stimulated by IL-4 and IL-13

Question 16

What are the results of Th1 immune response?

Answer 16

1) classical macrphage activation
2) complement binding
3) IgG

Question 17

What are the results of Th2 immune response?

Answer 17

1) Ab production
2) mast cell degranulation
3) intestinal mucous secretion and peristalsis
4) eosinophil activation
5) alternative macrophage activation

Question 18

What causes opsonization in Th1?

Answer 18

IFN-gamma – IgG

Question 19

What causes complement activation in Th1?

Answer 19

IFN-gamma – IgG

Question 20

What causes classical macrophage activation in Th1?

Answer 20

IFN-gamma (from Th1 CD4, Treg and NK)

Question 21

What causes Th1 differentiation/proliferation?

Answer 21

IL-12 (from macrophages, DCs) stimulates T cell to make IFN-gamma to cause feedback

Question 22

What causes Th2 differentiation/proliferation?

Answer 22

IL-4 (from mast, eosinophils) stimulates T cell to make IL-4 to cause feedback

Question 23

What causes alternative macrophage activation?

Answer 23

IL-4 and IL-13

Question 24

What causes intestinal mucous secretion and peristalsis?

Answer 24

IL-4 and IL-13

Question 25

What causes activation of eosinophils?

Answer 25

IL-5

Question 26

What causes production of IgE?

Answer 26

IL-4 targeting B cells

Question 27

What causes mast cell degranulation?

Answer 27

recognition of epsilon receptor of IgE

Question 28

What cytokines do Th2 CD4's produce?

Answer 28

IL-4, IL-5, IL-13

Question 29

What cytokines do Th1 CD4's produce?

Answer 29

IFN-gamma

Question 30

What do Tfh cells in Th1 produce?

Answer 30

IFN-gamma

Question 31

What do Tfh cells in Th2 produce?

Answer 31

IL-4

Question 32

How are helminths that are too large to be phagocytosed eliminated?

Answer 32

1) IgE binds | 2) mast cell degranulates

Question 33

What component (Th1/Th2) has best ADCC?

Answer 33

Th2

Question 34

What other Abs are involved in Th2?

Answer 34

IgA and IgG | -- both bind helminth to activate eosinophil degranulation

Question 35

How is IgA production stimulated?

Answer 35

TGF-beta

Question 36

How is IgG production stimulated?

Answer 36

IFN-gamma

Question 37

What immune response is required to fight trypanosomiasis and why?

Answer 37

Th2...trypomastigotes injected in bloodstream are never phagocytosed

Question 38

What are the hosts in trypanosomiasis?

Answer 38

tsetse fly + human

Question 39

Common name for trypanosomiasis?

Answer 39

african sleeping sickness

Question 40

What are the hosts in leishmaniasis?

Answer 40

female sandfly + mammals

Question 41

What are the stages of infection in malaria?

Answer 41

1) sporogonic 2) exo-erythrocytic 3) erythrocytic

Question 42

What is the sporogonic cycle in malaria?

Answer 42

mosquito stages, plus when mosquito injects sporozoites into human

Question 43

What is the exo-erythrocytic cycle in malaria?

Answer 43

1) injected sporozoites infect hepatocyte 2) form intracellular schizont 3) schizont ruptures and invades blood

Question 44

What is the erythrocytic cycle in malaria?

Answer 44

1) schizont infects RBC 2) trophozoite matures and ruptures 2) trophozoite forms gametocytes to be ingested by mosquito

Question 45

What organism is involved in hookworm?

Answer 45

Filariform larvae

Question 46

What are the stages of infection of hookworm?

Answer 46

1) infective: enters through unbroken skin, migrates to intestine 2) diagnostic: eggs spread in feces

Question 47

Describe the infection stages in leishmaniasis.

Answer 47

1) promastigotes invade macrophages, granulocytes, or are phagocytosed 2) multiply into amastigoes 3) leave and infect other cells

Question 48

How does leishmaniasis evade the immune system?

Answer 48

1) alters complement system 2) avoid innate mechanisms 3) modulate cytokines 4) inhibit Ag-presentation and T activation 5) alter T-cell differentiation

Question 49

How does leishmaniasis alter the host complement system?

Answer 49

phosphorylates complement proteins | sheds MAC

Question 50

How does leishmaniasis avoid innate mechanisms?

Answer 50

- - inhibits formation of phagolysosome - - scavenges ROS - - inhibits enzymes

Question 51

How does leishmaniasis modulate cytokines?

Answer 51

- suppresses activating cytokines | - induces inhibitory cytokines

Question 52

How does leishmaniasis inhibit antigen presentation/T activation?

Answer 52

- - suppresses MHC class II expression - - inhibits p-MHC formation - - downregulates B7

Question 53

How does leishmaniasis alter T-cell differentiation?

Answer 53

induces Th2 response