Lecture 124/125

Question 1

What are the functions of antibodies?

Answer 1

1. Immobilize pathogens
2. Neutralize toxins/viruses
3. Opsonize pathogens to enhance phagocytosis

Question 2

What region is the constant region of an antibody; interacts with immune cells or complement

Answer 2

Fc region

Question 3

Which immunoglobulin is a pentamer when secreted?

Answer 3

IgM

Question 4

What is the first antibody produced in a primary response?

Answer 4

IgM

Question 5

Which antibody is great at agglutination?

Answer 5

IgM

Question 6

Which antibodies activate complement?

Answer 6

IgM and IgG

Question 7

Which antibody is found on B-cell surfaces as a BCR?

Answer 7

IgD

Question 8

Which antibody appears as a second wave in antibody response?

Answer 8

IgG

Question 8

Which antibody is most abundant in serum?

Answer 8

IgG

Question 9

What antibody is primarily responsible for opsonization?

Answer 9

IgG

Question 10

Which antibody is responsible for antibody-dependent cell-mediated cytotoxicity (ADCC)?

Answer 10

IgG

Question 11

Which antibody crosses the placenta?

Answer 11

IgG

Question 12

Which antibody is abundant in mucosal areas?

Answer 12

IgA

Question 13

Which antibody is passed through breast milk?

Answer 13

IgA

Question 14

Which antibody is centrally involved in Type I Hypersensitivity?

Answer 14

IgE

Question 15

What cells does IgE bind avidly to?

Answer 15

Mast cells and eosinophils

Question 16

What antigen-antibody reaction results in insoluble complexes?

Answer 16

Precipitin

Question 17

Which antibodies are particularly effective at neutralization?

Answer 17

IgG and IgA

Question 18

Mast cell degranulation results in:

Answer 18

Release of histamine and other mediators

Question 19

Which hypersensitivity type is an antibody-dependent cytotoxic reaction?

Answer 19

Type II

Question 20

What happens in a type II hypersensitivity reaction?

Answer 20

IgM/IgG react with cell-surface or extracellular matrix antigens

Question 21

Clinical condition:

Hemolytic anemia results from ____ and is a type ____ hypersensitivity reaction

Answer 21

Blood group mismatch, type II

Question 22

What is the pathophysiology of Grave’s disease?

Answer 22

Type II hypersensitivity, autoantibody stimulates TSH receptor

Question 23

What is the pathophysiology of Myasthenia Gravis?

Answer 23

Type II hypersensitivity reaction, autoantibody blocks ACh receptor

Question 24

Rheumatic fever involves what type of hypersensitivity reaction?

Answer 24

Type II hypersensitivity reaction

Question 25

Type III hypersensitivity reactions are a:

Answer 25

Immune complex-mediated reaction (IgG)

Question 26

What is the mechanism of type III hypersensitivity reactions?

Answer 26

Formation of circulating Ag-Ab complexes that deposit in tissues, leading to vasculitis and inflammation

Question 27

What is an Arthus reaction?

Answer 27

Necrotizing vasculitis in a specific site; type III hypersensitivity

Question 28

What is an example of an exogenous cause of serum sickness?

Answer 28

Penicillin, non-human Abs

Question 29

What condition is an example of an endogenous cause of serum sickness?

Answer 29

SLE (or other autoimmune diseases)

Question 30

Type IV hypersensitivity reactions are a:

Answer 30

Delayed-type reaction (T-cell mediated)

Question 31

What is the time frame for type IV hypersensitivity reactions?

Answer 31

48-72 hours after exposure

Question 32

MHC I is found on:

Answer 32

All nucleated cells

Question 33

MHC presents ____ antigens

Answer 33

Intracellular

Question 34

MHC I is key for ____ T-cell recognition

Answer 34

CD8+

Question 35

What human genes are associated with MHC I?

Answer 35

HLA-A, -B, -C

Question 36

MHC II is primarily expressed on:

Answer 36

Antigen-presenting cells (APCs)

Question 37

MHC II presents ____ antigens

Answer 37

Extracellular

Question 38

MHC II is required for ____ T-cell activation

Answer 38

CD4+

Question 39

What human genes are associated with MHC II?

Answer 39

HLA-DP, -DQ, -DR

Question 40

What CD is found on all T-cells?

Answer 40

CD3

Question 41

What CD is associated with T-cell receptors to initiate signal transduction?

Answer 41

CD3

Question 42

What costimulatory molecule on T-cells binds to B7 on APCs?

Answer 42

CD28

Question 43

What happens if there is no costimulatory signal between an APC-T-helped cell interface?

Answer 43

T-cell anergy or apoptosis

Question 44

Th1 is driven by what cytokines?

Answer 44

IFN-y, IL-12

Question 45

What is the role of Th1?

Answer 45

Activate macorphages, support cell-mediate immunity

Question 46

Th2 differentiation is driven by what cytokines?

Answer 46

IL-4, IL-10

Question 47

What is the role of Th2?

Answer 47

Helps B-cells, supports humoral immunity

Question 48

What cytokines drive Th17 differentiation?

Answer 48

IL-6, TGF-b

Question 49

What is the role of Th17?

Answer 49

Pro-inflammatory, recruits neutrophils

Question 50

CD8+ cells require ____ for full activation

Answer 50

IL-2

Question 51

Once activated, CD8+ T-cells differentiate into:

Answer 51

Cytotoxic T lymphocytes (CTLs)

Question 52

What are Ti-1 antigens?

Answer 52

Polyclonal activators (LPS)

Question 53

What are Ti-2 antigens?

Answer 53

Large multivalent polysaccharides (bacterial capsules)

Question 54

What CDs are specific to B-cells?

Answer 54

CD19, CD20, CD21

Question 55

Th-dependent B-cell activation requires what co-signal to stimulate isotype class switching?

Answer 55

CD40L-CD40

Question 56

Stimulation by IL-4 during class switching results in production of:

Answer 56

IgE and IgG

Question 57

Stimulation by IL-5 during class switching results in production of:

Answer 57

IgA

Question 58

Stimulation by IL-13 during class switching results in production of:

Answer 58

IgE

Question 59

What three cytokines stimukate neutrophil chemotaxis?

Answer 59

C5a, LTB4, IL8

Question 60

What components of the complement system stimulate histamine release?

Answer 60

C3a, C4a, C5a