Trypanosomes - Disease Protists

Question 1

What do contemporary protists form?

Answer 1

Paraphyletic group

Question 2

Why do contemporary protists form paraphyletic group?

Answer 2

Doesn’t form a neat branch of closely related organisms

Question 3

What do Apicocomplexa cause?

Answer 3

Malaria, crypto, toxoplasmosis

Question 4

What do Entomoeba infection cause?

Answer 4

Amoebiasis

Question 5

What are excavates?

Answer 5

Ancient group diverged just after emergence of eukaryotes

Question 6

What are examples of excavates?

Answer 6

Parabasilids

Diplomonads

Question 7

What are kinetoplastids?

Answer 7

Mitochondria contains kinetoplast

Single flagellum attached to membrane

Question 8

What are kinetoplast?

Answer 8

A network of circular DNA inside a large mitochondrion that contains many copies of mitochondrial genomes

Question 9

Where do Trypanosomes live in?

Answer 9

Vertebrate blood

Question 10

What is the structure of Trypanosomes?

Answer 10

Mitochondria contains kinetoplast

Single flagellum attached to membrane

Question 11

What is Trypanosomes?

Answer 11

Vector-borne parasites

Question 12

What are the hosts of Trypanosomes?

Answer 12

All vertebrates clases

Question 13

What are the vectors of Trypanosomes?

Answer 13

Arthropod and leech vectors

Question 14

What are different types of pathogenic kinoplastids?

Answer 14

Leishmania
Trypanosoma bruci
Trypanosoma cruzi

Question 15

What disease does Trypanosoma cruzi cause?

Answer 15

Chagas Disease

Question 16

How many people are infected with Chagas disease?

Answer 16

8 million people

Question 17

How many people are infected with Chagas disease in USA?

Answer 17

300,000

Question 18

What are the vector for Trypanosoma cruzi?

Answer 18

Triatomine bugs

Question 19

What is the distribution of Chagas Disease?

Answer 19

• Different species of vector locally important cross distribution
• Basic form has common form of lifecycle
• Different stains are associated with particular forms of pathogenicity

Question 20

What are different forms of pathogenicity of different strains of Trypanosoma cruzi?

Answer 20

Actue form

Chronic form

Question 21

What subspecies of Trypanosomes infect humans in South and Central America?

Answer 21

Trypanosoma cruzi cruzi

Question 22

What are the subspecies of Trypanosomes that are morphologically identical to another form infecting bats and other bats?

Answer 22

Trypanosoma cruzi marinkellei

Trypanosome dionisii

Question 23

What are key life stages of Trypanosoma cruzi?

Answer 23

Trypomastigot
Amastigote
Epimastigote

Question 24

What is trypomastigote found?

Answer 24

Found in bloodstream of infected vertebrates

Question 25

What is amastigote found?

Answer 25

Intracellular dividing form in the cytoplasm of vertebrate cells

Question 26

Where is epimastigote found?

Answer 26

Found in insect vector

Question 27

What is life cycle of Trypanosoma cruzi?

Answer 27

1. Triatomia bug takes blood meal 2. Pass metacyclic trypomastigotes in faeces 3. Trypomastigote enters bite wound or mucosal membrane 4. Metacyclic trypomastigote penetrate various cells at bit wound site 5. Inside cell transform to amastigotes 6. Amastigote multiply by binary fission 7. Intracellular amastigote transform into trypomastigote then burst out of cell into bloodstream 8. Trypomastigote can infect other cells and repeat by cycle 9. Triatomine bug takes a blood meal 10. Epimastigote in midgut 11. Multiply in midgut 12. Metacyclic trypomastigotes in hindgut

Question 28

How does Trypanosome cruzi invade host?

Answer 28

Via feeding wound or mucosa

Question 29

What do Trypanosome cruzi infect?

Answer 29

Muscle, nerves and macrophages

Question 30

Where does the host localise in Trypanosome cruzi?

Answer 30

Cardiac muscle Smooth muscle Autonomic nerves Macrophages

Question 31

What is the immune evasion of Trypanosome cruzi?

Answer 31

- Intracellular multiplication (T cells) | - Can grow within macrophages

Question 32

How can Trypanosome cruzi grow within macrophages?

Answer 32

- Enter cell via the phagocytic vacuole - Quickly escape the vacuole and move into the cytoplasm - Safe from destructive enzymic activity

Question 33

What is the pathology I of chagas disease?

Answer 33

Acute phase

Question 34

What is the acute phase of chagas disease?

Answer 34

- Trypanosomes first infect mucous membranes then enter bloodstream - Symptoms: fever, fatigue, body aches, headache and rash - Serious in children and immunocompromised adults

Question 35

How long does acute phase last?

Answer 35

8-12 weeks

Question 36

What is the pathology II of chagas disease?

Answer 36

Chronic phase

Question 37

What is the chronic phase of chagas disease?

Answer 37

-Very low levels in blood -No symptoms for 10 years -Survive in cytoplasm of macrophages and muscle cells epithelial cells and neurones Intestinal lesions

Question 38

What is intestinal lesions?

Answer 38

Mega-syndrome of severe intestinal dilation

Question 39

What causes African sleeping sickness?

Answer 39

Trypanosoma brucei

Question 40

How many people were reported with African sleeping sickness in 2015?

Answer 40

2804 cases

Question 41

What are the vector of Trypanosoma brucei?

Answer 41

Tsetse flies

Question 42

What is the distribution of sleeping sickness?

Answer 42

- Eastern Africa = Trypanosoma brucei rhodesiense | - Western Africa = Trypanosoma brucei gambiense

Question 43

What are the two different forms of sleeping sickness?

Answer 43

- Trypanosoma brucei rhodesiense | - Trypanosoma brucei gambiense

Question 44

What are different between the two forms of sleeping sickness?

Answer 44

- Ecology | - Epidemiology

Question 45

What does the Trypanosoma brucei rhodesiense invade?

Answer 45

Widespread organ damage, acute

Question 46

What does the Trypanosoma brucei gambiense invade?

Answer 46

Central nervous system, chronic

Question 47

What is the life-cycle of sleeping sickness?

Answer 47

1. Tsetse fly takes blood meal 2. Inject metacyclic trypomastigotes 3. Injected metacyclic trypomastigotes transforms into bloodstream 4. Trypomastigotes multiple by binary fission in various body fluids 5. Trypomastigotes in blood 6. Tsetse fly takes blood meal 7. Bloodstream trypomastigotes ingested 8. Bloodstream trypomastigote transform into procyclic trypomastigote in tsetse fly's midgut and multiply by binary fission 9. Procyclic trypomastigote leave midgut and transform into epimastigotes 10. Epimastigotes multiply in salivary gland 11. Transform into metacyclic trypomastigote

Question 48

Do Trypanosoma brucei have a natural reservoir?

Answer 48

Yes

Question 49

Where does the host localise in Trypanosome brucei?

Answer 49

Blood, lymph, cerebrospinal fluid, brain

Question 50

What is the Trypanosome brucei parasite covered in?

Answer 50

Coat made up of variable surface glycoproteins

Question 51

How many identical glycoprotein molecules cover parasite surface?

Answer 51

>10 million

Question 52

What are variable surface glycoproteins?

Answer 52

Tightly packed, prevents immune recognition/antibodies and protects against lytic compounds in host serum

Question 53

What do variable surface glycoproteins do throughout course of infections?

Answer 53

Change

Question 54

What does the variable surface glycoproteins changing throughout course of infection allow?

Answer 54

Avoiding host immune system

Question 55

What do tsetse fly gut trypanosomes express on surface?

Answer 55

A single antigen called procyclin

Question 56

How many variable surface glycoprotein does mammalian host express?

Answer 56

+100 different ones

Question 57

How many variable surface glycoprotein are expressed at the same time?

Answer 57

Only one

Question 58

How many expression sites do Trypanosomes brucei have?

Answer 58

About 20

Question 59

What are the two main methods that lead to antigenic variation?

Answer 59

- Use of different variable surface glycoprotein expression site - DNA recombination changes variable surface glycoprotein present in active expression site

Question 60

What are the different pathology of sleeping sickness?

Answer 60

Stage 1: Skin lesion may form at bite site. Parasite enters the blood Stage 2: Parasite enters the nervous system Death

Question 61

True or false: | T. brucei contains kinetoplast

Answer 61

True

Question 62

True or false: | T. cruzi contains kinetoplast

Answer 62

True

Question 63

True or false: | T. brucei invade the CNS

Answer 63

True

Question 64

True or false: | T. cruzi invade the CNS

Answer 64

False

Question 65

True or false: | T. brucei infective forms in insect faeces

Answer 65

False, saliva

Question 66

True or false: | T. cruzi infective forms in insect faeces

Answer 66

True