8. Immuno

Question 1

To which lymph nodes do the sigmoid colon and the rectum drain?

Answer 1

sigmoid colon: inf mesenteric

upper rectum: inf mesenteric

lower (to pectinate line): int iliac

lower (below pec line): sup inguinal

Question 2

In what parts of the lymph nodes would B cells and T cells be located?

Answer 2

B cells: follicles (of the cortex)

T cells: paracortex

Question 3

Where would you find Peyer’s patches?

Answer 3

ileum (in lamina propria + submucosa)

Question 4

What molecules are expressed on the surface of antigen-presenting dendritic cells?

Answer 4

• MHC class 1, 2
• B7 protein
• CD40

Question 5

What 3 cell types are known for presenting antigens to CD4+ T cells?

Answer 5

• dendritic cells
• macrophages
• B cells

Question 6

What characteristic finding would you see on electron microscopy of a dendritic cell in a pt with Langerhans cell histiocytosis?

Answer 6

Birbeck granules (tennis racket)

Question 7

Which cytokines are produced by Th1 cells? by Th2 cells?

Answer 7

Th1 = IL-2, IFN-gamma 
Th2= IL-4, IL-5, IL-10

Question 8

Which cytokines inhibit Th1 cells? Which inhibit Th2 cells?

Answer 8

Th1 –> IL-10

Th2 –> IFN-gamma

Question 9

How do cytotoxic T cells kill virus-infected cells and neoplastic cells?

Answer 9

1. granzyme B + perforin

2. Fas-ligand on T-cell binds to Fas-receptor on target cell –> induce apoptosis

Question 10

Which surface markers are found on B-cells?

Answer 10

CD19, 20, 21 
IgM, IgD 
MHC class I, 2 
B7 protein 
CD40

Question 11

What immunoglobulin is associated with allergies b/c it is bound by mast cells and basophils and causes them to degranulate and release their histamine?

Answer 11

IgE

Question 12

What immunoglobulin comprises 70-75% of the total immunoglobulin pool?

Answer 12

IgG

Question 13

What immunoglobulin is present in large quantities on the surface of many B cells?

Answer 13

IgD, IgM

Question 14

What immunoglobulin crosses the placenta and additionally confers immunity to neonates in the first few months of life?

Answer 14

IgG

Question 15

What immunoglobulin can occur as a dimer?

Answer 15

IgA (secretory)

Question 16

What immunoglobulin is largely confined to the intravascular pool and is the predominant early antibody frequently seen in the immune response to infectious organisms with complex antigens?

Answer 16

IgM

Question 17

What immunoglobulin is distributed evenly b/w the intravascular and extravascular pools?

Answer 17

IgG

Question 18

What immunoglobulin is the predominant immunoglobulin in mucoserous secretions such as saliva, colostrum, milk, tracheobronchial secretions, and GU secretions?

Answer 18

IgA

Question 19

What immunoglobulin can be a pentamer?

Answer 19

IgM

Question 20

What initiates recombination of V(D)J sequences?

Answer 20

RAG-1, RAG-2

–> recombination activating genes

Question 21

Which viral vaccines are potentially dangerous to pts with an egg allergy? (2)

Answer 21

• influenza

- yellow fever

Question 22

What autoimmune disease is associated with anti-dsDNA antibodies?

Answer 22

SLE

Question 23

What stain is used to identify amyloid microscopically, and how is its appearance described?

Answer 23

congo red stain

- apple green birefringence under polarized light

Question 24

Which type of hypersensitivity is responsible for post-strep GN?

Answer 24

3

Question 25

Which type of hypersensitivity is responsible for asthma?

Answer 25

1

Question 26

Which type of hypersensitivity is responsible for rheumatic fever?

Answer 26

2

Question 27

Which type of hypersensitivity is responsible for tuberculosis skin test (PPD)?

Answer 27

4

Question 28

Which type of hypersensitivity is responsible for allergies, anaphylaxis, and hay fever?

Answer 28

1

Question 29

Which type of hypersensitivity is responsible for polyarteritis nodosa (PAN)?

Answer 29

3

Question 30

Which type of hypersensitivity is responsible for serum sickness?

Answer 30

3

Question 31

Which type of hypersensitivity is responsible for ABO blood type incompatibility?

Answer 31

2

Question 32

Which type of hypersensitivity is responsible for poison ivy?

Answer 32

4

Question 33

Which type of hypersensitivity is responsible for eczema?

Answer 33

1

Question 34

Which type of hypersensitivity is responsible for contact dermatitis?

Answer 34

4

Question 35

Which type of hypersensitivity is responsible for Goodpasture syndrome?

Answer 35

2

Question 36

A patient suffers from recurrent Neisseria infections. What complement proteins are deficient?

Answer 36

C5b - 9

Question 37

Which complement is responsible for neutrophil chemotaxis?

Answer 37

C5a

Question 38

What cytokines are produced by Th1 cells?

Answer 38

IL-2, IL-3, IFN-gamma

Question 39

What cytokines are produced by Th2 cells?

Answer 39

IL-2, IL-3, IL-4, IL-5, IL-10

Question 40

What cytokines promotes growth and differentiation of B cells?

Answer 40

IL-4, IL-5

Question 41

What cytokines promotes growth and activation of eosinophils?

Answer 41

IL-5

Question 42

What cytokines are pyrogens secreted by macrophages?

Answer 42

IL-1, IL-6

Question 43

What cytokines enhance synthesis of IgE and IgG

Answer 43

IL-4 (remember, BEG 4 it)

Question 44

What cytokines enhance synthesis of IgA

Answer 44

IL-5

Question 45

What cytokines mediate inflammation?

Answer 45

IL-1, IL-6, TNF-alpha

Question 46

What cytokines are secreted by Th1 cells and activate macrophages?

Answer 46

IFN-alpha

Question 47

What cytokines are secreted by Th2 cells and inhibits macrophage activation?

Answer 47

IL-10

Question 48

What cytokines inhibits production of Th1 cells?

Answer 48

IL-10

Question 49

What cytokines inhibits production of Th2 cells?

Answer 49

IFN-gamma

Question 50

What cytokines are released by virus-infected cells?

Answer 50

IFN-alpha, IFN-beta

Question 51

What cytokines supports growth and differentiation of bone marrow stem cells?

Answer 51

IL-3

Question 52

What cytokines supports T-cell proliferation, differentiation, and activation?

Answer 52

IL-2

Question 53

What is the function of macrophages in the spleen? (2)

Answer 53

1. remove encapsulated bacteria | 2. remove dysfunctional RBCs

Question 54

Which immunosuppressant is a precursor of 6-mercaptopurine?

Answer 54

azathioprine

Question 55

Which immunosuppressant inhibits IMP dehydrogenase?

Answer 55

mycophenolate

Question 56

Which immunosuppressant inhibits calcineurin resulting in the loss of IL-2 production and inhibition of T-cell differentiation and activation?

Answer 56

cyclosporin

Question 57

Which immunosuppressant binds FK-binding protein (FKBP) leading to loss of IL-2 production?

Answer 57

tacrolimus

Question 58

Which immunosuppressant binds FKBP12 leading to inhibition of mTOR and inhibition of T-cell proliferation?

Answer 58

sirolimus (rapamycin)

Question 59

Which immunosuppressant is used for lupus nephritis?

Answer 59

azathioprine | mycophenolate and cyclosporin used off-label

Question 60

Which immunosuppressant is metabolized by xanthine oxidase, therefore allopurinol increases its toxicity?

Answer 60

azathioprine

Question 61

What are the X-linked immunodeficiencies?

Answer 61

WACH - Wiskott-Aldrich syndrome - Agammaglobulinemia (Bruton) - Chronic granulomatous disease (CGD) - Hyper IgM syndrome

Question 62

What are the clinical features of Wiskott-Aldrich syndrome?

Answer 62

WAITER - Wiskott - Aldrich - Immunodeficiency - Thrombocytopenia + purpura - Eczema - Recurrent pyogenic infections - low IgM, high IgA

Question 63

What is the cause of chronic granulomatous disease (CGD)? To what infections are these individuals susceptible?

Answer 63

- absence of NADPH oxidase | - susceptible to catalase + pathogens (esp. S. aureus, aspergillus)

Question 64

A young child presents with tetany from hypocalcemia, and candidiasis resulting from immunosuppression. What cell type is deficient in this patient?

Answer 64

T-cell (DiGeorge; thymic aplasia)