2: Components of the Immune System

Question 1

What are cytokines?

Answer 1

Collection of small proteins and peptides

Question 2

What do cytokines do?

Answer 2

Modulate behaviour of cells - coordinate immune system

Question 3

Name two processes which cytokines are produced in response to.

Answer 3

Infection
Inflammation
Tissue damage

Question 4

What function do interferons have?

Answer 4

Anti-viral activity

Question 5

What does TNF(alpha) do?

Answer 5

Promotes inflammation

Question 6

What do chemokines do?

Answer 6

Control and direct cell migration

Question 7

What is an antigen?

Answer 7

Any substance which can stimulate an immune response

Question 8

What is an antibody?

Answer 8

A protein which is

1. produced in response to an antigen
   AND
2. binds specifically to that antigen

Question 9

What kind of cell produces antibodies?

Answer 9

B cells

Question 10

What do antibodies protect against?

Answer 10

Extracellular pathogens
Viruses
Toxins

Question 11

What are Natural Killer cells?

Answer 11

Large granular lymphocytes

Question 12

What are B cells?

Answer 12

Lymphocytes which produce antibodies to protect against EXTRACELLULAR pathogens

Question 13

What are T cells?

Answer 13

Lymphocytes which defend against INTRACELLULAR pathogens

Question 14

What do helper T cells do?

Answer 14

Regulate the immune system

Question 15

What do cytotoxic T cells do?

Answer 15

Kill virally infected cells

Question 16

Where do mature T and B cells circulate?

Answer 16

Blood, lymph and secondary lymphoid tissues

Question 17

T and B cells are ___ until they meet a pathogen/antigen.

Answer 17

inactive

Question 18

What are long-lived T and B cells called?

Answer 18

Memory cells

Question 19

Describe immunological memory.

Answer 19

Once the ADAPTIVE immune system recognised and responded to an antigen, it exhibits life-long immunity to that antigen (through memory T and memory B cells).

Question 20

Which cells protect mucosal surfaces?

Answer 20

Mast cells

Question 21

Where do mast cells reside?

Answer 21

In tissues

Question 22

Which cells are recruited to sites of infection by inflammatory signals?

Answer 22

Basophils and eosinophils

Question 23

Where do basophils and eosinophils reside?

Answer 23

They circulate in the blood

Question 24

Mast cells, basophils & eosinophils are highly ____ cells.

Answer 24

granular

Question 25

Mast cells, basophils and eosinophils release chemicals which contribute to acute inflammation - what are they called?

Answer 25

Histamine Heparin Other cytokines

Question 26

Mast cells, basophils and eosinophils help defend against large pathogens which cannot be phagocytosed, such as...?

Answer 26

Parasitic worms

Question 27

Mast cells, basophils and eosinophils have a key role in mediating which kind of response?

Answer 27

Allergic responses

Question 28

What is the complement system?

Answer 28

A family of approx. 30 different proteins which promote inflammation

Question 29

Where are complement proteins produced?

Answer 29

In the liver

Question 30

Complement proteins circulate in the blood as ____ ____.

Answer 30

inactive precursors

Question 31

Complement proteins activate when they enter ___/___ tissue.

Answer 31

infected/inflamed

Question 32

Complement proteins cleave and activate downstream complement proteins - what is this event called?

Answer 32

Complement cascade

Question 33

Name three examples of phagocytic cells.

Answer 33

Monocytes Macrophages Neutrophils

Question 34

By which process do phagocytic cells ingest and destroy pathogens?

Answer 34

Phagocytosis

Question 35

Which cells differentiate into macrophages after migrating into tissues?

Answer 35

Monocytes

Question 36

Describe three functions of macrophages OTHER than pathogen killing.

Answer 36

Limiting inflammation Wound healing/tissue repair Antigen presentation

Question 37

What are neutrophils also known as?

Answer 37

Polymorphs

Question 38

Why are neutrophils also known as polymorphs?

Answer 38

Their nuclei have three lobes

Question 39

Where are neutrophils found before their recruitment into infected or inflamed tissues?

Answer 39

The blood

Question 40

What is the main purpose of dendritic cells?

Answer 40

Antigen presentation to T cells

Question 41

What occurs in primary lymphoid tissues?

Answer 41

Development of leukocytes

Question 42

Give two examples of primary lymphoid tissue.

Answer 42

Bone marrow | Thymus

Question 43

What occurs in secondary lymphoid tissues?

Answer 43

Adaptive immune responses

Question 44

Which leukocytes may be found in secondary lymphoid tissues?

Answer 44

T cells B cells Dendritic cells

Question 45

Give two examples of secondary lymphoid tissues.

Answer 45

Lymph nodes Tonsils Spleen Peyer's patches

Question 46

What do lymphatic vessels do?

Answer 46

Drain lymph from body tissues

Question 47

Where are pathogens/antigens trapped?

Answer 47

Lymph nodes

Question 48

What is lymphoedema also known as?

Answer 48

Lymphatic obstruction

Question 49

What occurs in lymphoedema and why?

Answer 49

Fluid retention and swelling - due to compromised lymphatic system

Question 50

Lymphoedema sufferers are at high risk of ____.

Answer 50

infection