Adaptive Immunity

Question 1

What are the two kinds of immunity?

Answer 1

Innate and adaptive

Question 2

What is the kind of cell that sees the pathogens first?

Answer 2

Dendritic cells and macrophages

Question 3

If a a bacterial infection is present then which cells are the first ones to appear?

Answer 3

Neutrophils

Question 4

In what case are natural killer cells and lymphocytes the first ones to appear?

Answer 4

Viral infections

Question 5

What are the cellular components of adaptive immunity?

Answer 5

T-cells and B-cells

Question 6

What kind of immunity do T-cells provide?

Answer 6

Cell-mediated immunity

Question 7

Which kind of cells provide humoral immunity?

Answer 7

B-cells

Question 8

What receptors do B-cells have?

Answer 8

B-cell receptors which activate immunity

Question 9

What receptors do T-cells have?

Answer 9

T-cell receptors to detect antigens

Question 10

Where are T-cells and B-cells developed?

Answer 10

T-cells; thymus
B-cells; bone marrow

Question 11

What kind of receptors do monocytes have?

Answer 11

CD44

Question 12

What happens when CD44 receptors get engaged?

Answer 12

They get engaged when they come in contact with the antigen, causes receptors to enlarge and change the structure and function of the monocyte developing it to a macrophage.

Question 13

Where are B-cells and T-cells most commonly found?

Answer 13

The lymph-nodes

Question 14

Where are the receptors of a phagosome?

Answer 14

Intracellularly

Question 15

Why is the swelling response of inflammation beneficial?

Answer 15

Leakage fluid accumulates in the lymph nodes through the lymphatic system, that also allows dendritic cells to move towards the lymph-nodes too.

Question 16

Why is it important that an infection does not escape from the lymph-nodes to the circulatory system?

Answer 16

If it is in the blood-stream it will have access to all tissues and organs.

Question 17

What are antigens?

Answer 17

Any substance that can trigger the immune system of the body

Question 18

What are examples of pathogenic-antigens?

Answer 18

Proteins, nucleic acids, carbohydrates and lipids.

Question 19

What are self-antigens?

Answer 19

The individual’s own proteins, nucleic acids, carbohydrates or lipids that can act as antigens in other people

Question 20

What happens if an antigen is too small, what is considered too small?

Answer 20

A molecular weight less than 10000 Da
It will not trigger a response unless attached to a carrier

Question 21

What are small antigens known as?

Answer 21

Haptens

Question 22

What are examples of haptens?

Answer 22

Cosmetics, hair dyes, animal dander, chemicals

Question 23

What is immunogenicity?

Answer 23

The ability to generate an immune response

Question 24

What is antigenicity?

Answer 24

The ability to attach to an antigen, may or may not cause an immune response

Question 25

Which immunogens are antigenic?

Answer 25

All immunogens are antigenic but not all antigenic substances cause an immune response

Question 26

What are mature T-lymphocytes and where are they found?

Answer 26

They are T-cells that have undergone the process of maturation, they are not in cells, they are either in the circulation or the lymph nodes.

Question 27

After how many days would there be an increase in lymphocytes if an infection is present?

Answer 27

7 days

Question 28

What are mature-naive lymphocytes?

Answer 28

They are B and T cells that have gone through the whole maturation process but they are yet to be exposed to the pathogen.

Question 29

Where do the lymphocytes destined to become T-cells go?

Answer 29

They migrate through the blood to the thymus and develop immunocompetence there

Question 30

Where do B-cells develop immunocompetence?

Answer 30

In the red bone marrow

Question 31

Which kind of lymphocytes leave the thymus and bone marrow?

Answer 31

Immunocompetent but still naive lymphocytes

Question 32

Where do lymphocytes encounter their antigen and become activated?

Answer 32

The lymph nodes, spleen and other lymphoid tissues

Question 33

When do lymphocytes mature?

Answer 33

When they come in contact with their antigen

Question 34

What do mature immunocompetent lymphocytes do?

Answer 34

They circulate continuously in the bloodstream and lymph and through-out the lymphoid organs of the body.

Question 35

What are the factors influencing antigen strength?

Answer 35

Molecular type Deviation from self Size Heterogeneity Capacity to be broken down

Question 37

What is the molecular type order from the most antigenic to the least?

Answer 37

Proteins, CHO, Lipids, DNA/RNA

Question 37

How does deviation from self affect antigenicity?

Question 38

How does size affect antigenicity?

Answer 38

The greater the weight, the greater the chance it activates an immune response

Question 39

What are antigen epitopes or determinants?

Answer 39

Small regions that allow for specific recognition of antigen, where antigens attach

Question 39

What are the two categories under heterogeneity that can affect antigenicity?

Answer 39

Structure Composition

Question 39

What is the B-cell receptor made up of?

Answer 39

The antibody associated with lgβ and lgα chains

Question 39

What are the light chains linked with?

Answer 39

Disulphide bond

Question 39

Why do the chains at the end of the BCR require proteins?

Answer 39

To transport to the nucleus, cannot do it themselves because they are too small

Question 40

What are the different examples of antigens?

Answer 40

Microbes Non-microbes Lipids Hapten

Question 41

What are microbe antigens?

Answer 41

Capsules, Cell walls, Toxins, Viral capsids, Flagella

Question 42

What are non-microbe antigens?

Answer 42

Pollen Egg white Red blood cell surface molecules Serum proteins Surface molecules from transplanted tissue

Question 42

What are lipid antigens?

Answer 42

Lipids and nucleic acids are mainly antigenic when combined with proteins or polysaccharides

Question 43

What are hapten antigens?

Answer 43

Small foreign molecules that are NOT antigenic, must be coupled to a carrier molecule t be antigenic.

Question 44

When will the hapten be recognised?

Answer 44

Once antibodies are formed

Question 45

Why does immunogenicity increase based on the number of epitopes?

Answer 45

More epitopes, more antigens able to attach

Question 46

Which kind of epitope is recognised immediately because of its straights sequence?

Answer 46

Linear epitope

Question 47

What is a cryptic epitope?

Answer 47

It can only be reached once phagocytosis is done and the protein has denatured

Question 48

What do B-cells recognize? How?

Answer 48

Free soluble antigen in the blood or lymph by their receptors

Question 49

What are B-cell receptors?

Answer 49

Membrane-bound immunoglobulins

Question 50

What are the two possible processes after cell proliferation?

Answer 50

Clone of plasma cells Clone of memory cells

Question 51

Do small amounts of a virus elicit an immune response?

Answer 51

No, not a lot of antigens so no immune response

Question 52

What is the process of B-cells?

Answer 52

Each B-cell has different antigen receptors (one antigen per receptor) In the presence of cytokines, this B-cell is stimulated to divide (clonal expansion) It will divide into plasma cells or memory B-cells

Question 53

Where do the cytokines come from?

Answer 53

T-cells

Question 54

Why do plasma cells have no receptors?

Answer 54

Their main purpose is to identify the antibody then die off

Question 55

What is the main function of plasma cells?

Answer 55

To secrete antibodies

Question 56

How is adaptive immunity mediated?

Answer 56

Through antibodies or immunoglobulins

Question 57

What are the five major classes of antibodies?

Answer 57

IgM IgA IgG IgE IgD

Question 58

What is the function of the antibodies?

Answer 58

To recognise and bind corresponding antigen

Question 59

What is the structure of the antibody?

Answer 59

There are 2 N-termini and 1 C-termini There are 2 identical heavy and light chains in the N-termini The C-termini chains have two carbohydrates attached Everything is linked by disulphide bonds

Question 60

What are antibodies composed of?

Answer 60

Polypeptides with variable and constant regions

Question 61

What are the variable regions?

Answer 61

Involved in antigen recognition & binding

Question 62

What are the constant regions?

Answer 62

Interact with immune system components

Question 63

What protein is involved in the proteolytic cleavage of the IgG?

Answer 63

Papain, which forms three structures

Question 64

What does papain produce?

Answer 64

The two Fab and one Fc segments

Question 65

What happens after the protein-protein interaction (antigen-antibody)?

Answer 65

Changes the structure and conformation of the Fc fragment which exposes the binding site and allows Fc to bind to antibody

Question 66

What determines the Ab type?

Answer 66

H-chain constant region

Question 67

What are the heavy chain isotopes?

Answer 67

γ heavy chain μ heavy chain δ heavy chain α heavy chain ε heavy chain

Question 68

What are the subtypes of γ heavy chain?

Answer 68

IgG1 to IgG4

Question 69

What are the subtypes of the α heavy chain?

Answer 69

IgA1 and IgA2

Question 70

Where does the variable segment of the H chain lie in antibody synthesis?

Answer 70

Upstream of the constant region of the H chain

Question 71

When does transcription take place?

Answer 71

A point before the Cγ3

Question 72

What happens to the RNA during antibody synthesis?

Answer 72

Spliced in 2 ways m-RNA for μ heavy chain

Question 73

What happens to the m-RNA for μ heavy chain?

Answer 73

IgM or δ-heavy chain

Question 74

What does δ-heavy chain become?

Answer 74

IgD

Question 75

What does polyadenylation splicing produce?

Answer 75

IgM or IgD