1.1 Basic concepts in immunology

Question 1

Immune system function:

Answer 1

Protect the host from infection
- detection and destruction of infectious organisms​
- remember what they look like, in case they come back (memory)

Question 2

Immune system structure types:

Answer 2

• white blood cells
• lymphoid tissues

Question 3

2 types of host immune response:

Answer 3

1. innate immunity
2. adaptive​ immunity

Question 4

Innate immunity:

Answer 4

• tries to keep foreign organisms out
• can recognize that infection is present and respond quickly

Question 5

adaptive​ immunity:

Answer 5

• much more efficient, slower to react
• helps innate immunity work better

Question 6

Innate immunity detection strategy​:

Answer 6

Uses pathogen-associated molecular patterns (PAMPs) to recognize molecules that are intrinsically foreign

• Neutrophils + tissue macrophage target bacteria
• eosinophils + tissue mast cells target parasites

Question 7

Have broadly reactive receptors that arent very specific?

Answer 7

innate immunity

Question 8

neutrophils + tissue macrophage target?

Answer 8

bacteria

Question 9

eosinphils ​+ tissue mast cells target?

Answer 9

parasites

Question 10

PAMPs: LPS =

Answer 10

LPS = gram -VE bacteria

Question 11

PAMPs: Peptidoglycan =

Answer 11

Peptidoglycan = gram -VE bacteria

Question 12

issue with innate immunity?

Answer 12

innate immunity and PAMPs:
- viruses have a ​simple structure, less obvious PAMPs
- some bacteria produce capsule to hide PAMPs

Question 13

Addaptive immunity is expressed by ?

Answer 13

Lymphocytes

Question 14

Lymphocytes:

Answer 14

• recognizes foreign antigen
• Highly specific detection system

Question 15

antigenic epitope:

Answer 15

small region of foreign antigen

Question 16

Antigen:

Answer 16

structural protein of pathogen

Question 17

Primary role of Lymphocytes?

Answer 17

• Have T cells and B cells
• primary role = dealing with viruses

**assist innate immunity bacterial and parasite infections

Question 18

B cell receptor:

Answer 18

bind WHOLE antigen on surface of pathagen in ECF

Question 19

B cell response to infection:

Answer 19

Question 20

T cell receptor:

Answer 20

recognizes DIGESTED antigen (peptides) displaced on surface

Question 21

role of immunolgical ​synapse:

Answer 21

gets info about infection from 1 cell to another cell

Question 22

Where does the lymphocyte develop?

Answer 22

Bone marrow
- develops unique antigen receptor

Question 23

When the receptor binds to an antigen it recognizes?

Answer 23

the lymphocyte is activated
- only lymphocyte activated is the one that recognizes that specific antigen
- this means only a few will react out of thousands

**think of blind men and elephant

Question 24

Which clonal type recognizes infection?

Answer 24

2

Question 25

Jobs once activated: B cells

Answer 25

produce antibodies —> stick to pathogen

Question 26

Jobs once activated: CD4 T helper cells

Answer 26

produce cytokines —> these activate other cells

Question 27

Jobs once activated: CD8 killer T cells

Answer 27

seek out and destroy​ virus-infected​ cells

Question 28

Antibody:

Answer 28

antigen binding protein
- targets the external surface of the pathogen like a molecular heat seeking​ missle

Question 29

What happens once an antibody is bound to a pathogen?

Answer 29

• inactivates/neutralizes it
• attracts phagocytic cells to eat it
• triggers​ innate killing response (complement cascade)

Question 30

Cytokines are used to:

Answer 30

• activate macrophage
• assist B cells in making antibodies

Question 31

Lymphocyte clones =

Answer 31

lymphocyte memory
- in case the pathogen returns
- allows the ​immune system to respond much more quickly than previously
- Host develops immunity / immunological memory