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Flashcards in Immunology Deck (181)
1

Primary lymphoid organs (2):

Thymus
Bone marrow

2

Site of B cell localization in a lymph node:

Follicle

3

Where the T cells in a lymph node are located:

Paracortex
(This is right next to the follicle)

4

Portion of a lymph node that becomes hugely enlarged in a robust cellular immune response:

Paracortex

5

Why do lymph nodes not enlarge in patients with DiGeorge?

They have no T cells. The paracortex, or T cell region, is what enlarges when a lymph node swells.

6

Where are the high endothelial venules of lymph nodes located?

Paracortex
T and B cells enter here

7

The primary lymph node drainage site for the upper limb and lateral breast:

Axillary

8

The primary lymph node drainage site for the stomach:

Celiac nodes

9

The primary lymph node drainage site for the duodenum and jejunum:

Superior mesenteric nodes

10

The primary lymph node drainage site for the sigmoid colon:

Colic nodes, which drain to inferior mesenteric nodes

11

The primary lymph node drainage site for the rectum above the pectinate line:

Internal iliac nodes

12

The primary lymph node drainage site for the anal canal below the pectinate line:

Superficial inguinal nodes

13

The primary lymph node drainage site for the testes:

Superficial and deep para-aortic plexes

14

The primary lymph node drainage site for the scrotum:

Superficial inguinal nodes

15

What does the right lymphatic duct drain? What happens if you obstruct this duct or it gets damaged?

The right arm, chest, and right half of the head.
Damage -> non-pitting edema of RUE.

16

Where does the thoracic duct empty?

Jx of L subclavian and IJ

17

Three ways you can become asplenic:

Sickle cell
Trauma
Surgery (eg for spherocytosis)

18

Where are T cells in the spleen?

They live in the peri-arteriolar lymphatic sheath (PALS).
Remember, P for Paracortex (LN) and PALS (spleen).

19

Where are B cells found in the spleen?

In the follicles in the white pulp.

20

T/F: T cells are found in the red pulp of the spleen.

F. PALS is where they live, this is in the white pulp.

21

Post-splenectomy, 3 buzzwords:

Howell-Jolly bodies
Target cells
Thrombocytosis

22

Asplenia renders someone vulnerable to what organisms? Which do we have vaccines for?

Encapsulated ones. Even Some Killers Have Pretty Nice Capsules:
E. coli
Strep pneumo *
Klebsiella
H. influenzae *
Pseudomonas
Neisseria (mening. and gonococcal *)
Cryptococcus

23

From what embryonic structure does the thymus come? What other structure develops from this origin?

The 3rd branchial pouch. Inferior parathyroids develop with the thymus.

24

In the thymus, where do mature T cells live? What kind of selection are they undergoing here?

Mature T cells live in the Medulla of the thymus, here they are undergoing (-) selection (learning not to kill the host cells).

25

In the thymus, where do immature T cells live? What kind of selection are they going through here?

Immature T cells live in the cortex.
Mature live in the Medulla.
They are undergoing (+) selection and learning to talk MHC.

26

The HLA subtypes associated with MHC I:

HLA-A
HLA-B
HLA-C

27

To what co-receptor does MHC I bind? MHC II?

CD8
CD4

28

Which cells express MHC I?
Which cells express MHC II?

MHC I is on the surface of all nucleated cells.
MHC II is only on APCs (macs, B cells, dendritic cells).

29

Which HLA subtypes are associated with MHC II?

Dr. is going to DQ to get a DrPepper.
HLA-DR
HLA-DQ
HLA-DP

30

Which MHC molecule needs to travel with b2 microglobulin to be displayed?

MHC I

31

HLA associated with hemochromatosis:

HLA-A3

32

HLA associated with the seronegative arthropathies:
Can you name 4 of these illnesses?

HLA-B27
Ank. spondylitis, Reiters / reactive arthritis, IBD, psoriatic arthritis

33

HLA subtypes associated with celiac disease:

HLA-DQ2 / DQ8

34

HLA subtypes associated with MS, hay fever, SLE, and Goodpasture's

HLA-DR2

35

HLA associated with type 1 diabetes (2):

HLA-DR3 / DR4

36

HLA associated with pernicious anemia:

HLA-DR5

37

Two surface markers for NK cells:

CD-16
CD-56

38

T/F: NK cells require T cell help to induce apoptosis of infected / cancerous cells:

F. They use perforin and granzymes on their own, respond to coded antigen and absence of MHC I.

39

Cytokines that enhance NK cell activity:

IL-2
IL-12
IFN-b
IFN-a

40

NK cells secrete this cytokine to activate macrophages:

IFN-g

41

What does CD-16 do and what cell types carry it?

Killers have it (macs, neut, monos, NK).
It binds the constant region of Ab and targets the Ab bearing cell for destruction.

42

Cell type that mediates hyperacute organ rejection:

B cells

43

TH1 cells secrete two main stimulatory cytokines. What do they do?

IFN-g calls out to macrophages
IFN-g also inhibits other T cells from going down the TH2 path
IL-2 stimulates T cells, NK cells

44

This cytokine is secreted by TH2 cells to inhibit TH1 cell development:

IL-10

45

These two cytokines are secreted by TH2 cells and stimulate B cells:

IL-4
IL-5

46

This interleukin drives TH1 development, where this interleukin drives TH2 development:

IL-12 drives TH1
IL-4 drives TH2

47

Which cell is the only cell that can activate a naive T cell?

Dendritic cell

48

Three APCs:

Dendritic cell
Macrophage
B cell

49

A naive T cell requires MHC + antigen + appropriate co-stimulation. What are these costimulatory molecules? A B cell requires a different pair of costimulatory moleucles, what are they?

CD28 on the T cell
CD80 = CD86 = B7 on the dendritic cell

CD40 on the B cell
CD40 ligand on the T cell

50

The macrophage activating cytokine:

IFN-g

51

Two cytokines that inhibit TH1 cells:

IL-4
IL-10
(both from TH2 cells)

52

Cytokine TH1 cells secrete that inhibits TH2 cells:

IFN-g

53

Four buzz-words for cytotoxic T cell killing mechanisms:

Perforin (enters cell)
Granzyme (serine protease)
Granulysin
FAS ligand (+ FAS receptor on host cells)

54

Three things expressed on the surface of regulatory T cells?

CD3
CD4
CD25

55

Where does complement bind an Ab?

The Fc, CH2 region (just below the hinge).

56

Gene products responsible for VDJ recombination. What do these proteins recognize?

RAG1 & RAG2
Recognize recombination signal sequences = RSSs

57

There are two light chains in human Ab:
What is the normal ratio in humans?

kappa
lambda
2K:1L

58

Most abundant Ab:

IgG

59

Crosses the placenta:

IgG

60

Life expectancy of a maternal Ab in a baby:

~21d

61

Ab that is a dimer when secreted:

IgA

62

Ab that is found in colostrum:

IgA

63

Ab that mediates type I hypersensitivity:

IgE

64

Ab that fixes complement (2):

IgG, IgM

65

This Ab prevents attachment of bacteria to mucous membranes:
T/F: It fixes complement.

IgA
F. No.

66

Two antibodies involved in the classic pathway of complement activation:

IgG
IgM

67

Triggers for each of the following complement pathways:
1. Classic
2. Lectin
3. Alternative

1. Classic = Ab mediated (IgG, IgM)
2. Leptin = mannose binding protein made by the liver
3. Alternative = molecules on the microbe

68

Complement protein for neutrophil chemotaxis:
Two other neutrophil chemotactic proteins:

C5a
IL-8, leukotriene B4

69

Complement proteins (2) responsible for anaphylaxis:

C3a, C5a for *A*naphylaxis

70

Complement proteins involved in forming the membrane attack complex:

C5b-9

71

Two complement proteins that help prevent complement from activating on self cells:

Decay-accelarating factor (DAF)
C1 esterase inhibitor = C1 esterase = C1 inhibitor

72

What is C1 esterase?

An inhibitor of the complement cascade, prevents host cells from being attacked by complement.

73

What does C1 esterase deficiency cause?

Hereditary angioedema.

74

You do not give this medicine to patients with C1 esterase deficiency. Why?

ACEi
C1 esterase def -> increased bradykinin, ACEi can also increase bradykinin

75

What happens to people who have a C3 deficiency?

They cannot coat bacteria with C3. They end up with severe recurrent pyogenic sinus / resp tract infections.

76

C3 deficiency, in addition to being associated with infection, is also associated with a hypersensitivity reaction:

Type III (glomerulonephritis)

77

Deficiencies in C5-9 lead to susceptibility to infection with what kind of organisms?

Neisserii. We got both kinds.

78

What is the complement defeciency associated with paroxysmal nocturnal hemoglobinuria?

Deficiency in decay accelerating factor, an inhibitory protein.

79

DAF deficiency... what happens?

RBCs lyse (complement-mediated)
You get paroxysmal nocturnal hemoglobinuria.

80

These three acute phase reactants are secreted by macrophages:

IL-1
IL-6
TNF-a

81

This is the major chemotactic factor for neutrophils:

IL-8
(C5a, leukotriene B)

82

Two interleukins that act as pyrogens:

IL-1
IL-6

83

The cytokine of septic shock:

TNF-a

84

What does IL-3 do?
IL-4?

Hot T-Bone stEAk:
IL-3 stimulates Bone marrow stem cells
IL-4 drives IgE production

85

Major T cell growth interleukin (all kinds of T cells):

IL-2

86

What is the function of IFN-g?

Activates NK, TH1, macrophages.
Suppresses TH2.
Antiviral / anti-tumor.

87

What cell secretes these cytokines: IL-1, IL-6, IL-8, TNF-a:

Macrophages

88

What is the function of a and b interferons?
g interferons?

a- and b- inhibit viral protein synthesis.
IFN-g upregulates MHC I and II and antigen presentation.

89

Unique marker for T cells:

CD3

90

Unique marker for helper T cells:
Cytotoxic T cells:

CD4
CD8

91

Epsterin-Barr virus docks at this protein on the surface of B cells:

CD21
B at the Barr when you are 21.

92

Protein carried by all APCs:

CD40

93

What is special about CD56?

It is the unique marker for NK cells.

94

This molecule binds the Fc of IgG:

CD16

95

Four exposures you might want to consider passively immunizing someone for:

Tetanus
Botulism
HBV
Rabies

96

If you want to confer passive immunity to someone, how often would you need to dose them?

Roughly monthly. t1/2 =~3w.

97

These vaccines are live-attenuated:

MMR
Oral polio = sabin
Varicella
Yellow fever
Intranasal flu

98

These two vaccines are egg based, contraindicated in people with severe allergies:

Flu
Yellow fever
(MMR technically, though not a problem in administration)

99

Which of the polio vaccines is live?

Oral is live (Sabin)
Injectable is inactivated (Salk)

100

Live or killed? Cholera:

Killed

101

Live or killed? Yellow fever:

Live

102

Live or killed? Sabin polio:

= Oral
Live

103

Live or killed? Hep A vaccine:

Killed

104

Live or killed? Rabies vaccine:

Killed

105

Live or killed? MMR:

Killed

106

The three hypersensitivity reactions that are mediated by antibodies?
The one mediated by cells?

I-III are Ab mediated
IV is cell-mediated

107

Hypersensitivity associated with IgE:

Type I

108

Hypersensitivity associated with IgM / IgG vs. cells:

Type II

109

Hypersensitivity associated with delayed response:

Type IV

110

Hypersensitivity associated with immune complex formation and neutrophil activation:

Type III

111

What causes the Arthus reaction? What kind of hypersensitivity is this?

Antigen-Ab complexes in the skin get attacked by neutrophils. This is Type III hypersensitivity.

112

What is serum sickness?

Give someone foreign proteins.
Ab vs foreign proteins are made by host.
These Ab form complexes that deposit on membranes, inflammation causes damage.
This is Type III hypersensitivity.

113

The 3 things stuck together in type III hypersensitivity:

Antigen
Ab
Complement

114

PSGN is an example of this kind of hypersensitivity:

Type III (Ab vs. antigen depositing in tissues)

115

Rheumatic fever is an example of this kind of hypersensitivity:

Type II (Ab vs. self)

116

Allergic and atopic disorders fall into the category of this kind of hypersensitivity:

Type I

117

Multiple sclerosis is an example of this kind of hypersensitivity:

Type IV

118

The PPD test for TB is an example of this kind of hypersensitivity:

Type IV

119

Pernicious anemia is an example of this kind of hypersensitivity:

Type II (Ab vs host protein)

120

Goodpasture syndrome is an example of this kind of hypersensitivity:

Type II (anti-GBM Ab, NOT immune complex deposition)

121

SLE and RA are both an example of this kind of hypersensitivity:

Type III, oddly.

122

Acute hemolytic transfusion reaction... what type of hypersensitivity am I?

Type II.
Can be intravascular (ABO incompatible) or extravascular (host Ab vs. foreign antigen on donor cell).

123

What kinds of infections would someone who had no granulocytes be vulnerable to (4)?

Staph
Brukholderia cepacia
Serratia
Nocardia

124

Someone with no B cells would be particularly vulnerable to this viral infection:

Enteroviral encephalitis

125

Anti-dsDNA is most commonly seen in this autoimmune disorder:

SLE (more specific for renal involvement)

126

Anti-Smith Ab are seen in:

SLE

127

Anti-histone Ab are most commonly seen in this autoimmune disorder:

DIL

128

You measure a positive RF for someone you suspect has RA. What is your confirmatory test?

Anti-CCP Ab

129

Ab associated with sceroderma:

Anti-centromere (CREST)
Anti-Scl-70 (diffuse)

130

Antimitochondrial Ab are found in this disease:

Primary biliary cirrhosis

131

Anti-endomysial Ab:

Celiac disease

132

Ab for Goodpasture syndrome:

Anti-BM

133

Ab for Hashimoto (2):

Anti-thyroglobulin
Anti-microsomal

134

Anti-desmoglein Ab are most commonly seen in this autoimmune disorder:

Pemphigus vulgaris

135

You suspect Sjogren syndrome. Order these two Ab titers especially:

Anti-Ro (SSA)
Anti-La (SSB)

136

Anti-smooth muscle Ab are seen with this disease:

Autoimmune hepatitis

137

c-ANCA Ab are seen in this illness:

Granulomatosis with polyangiitis (Wegener's granulomatosis)

138

p-ANCA Ab are seen in these disorders (2):

Microscopic polyangiitis
Churg-Strauss syndrome

139

These two Ab may mark Type 1 DM:

Anti-islet cell Ab
Anti-glutamate decarboxylase Ab

140

You suspect autoimmune hepatitis. What Ab titer do you order?

Anti-smooth muscle Ab

141

A deficiency of this cell type would leave someone particularly prone to GI giardiasis. Why?

B cells
There is no IgA to guard the gut

142

The three main X-linked immunodeficiencies you deemed it prudent to study:

Wiskott-Aldrich
Bruton's agammaglobulinemia
CGD
Hyper-IgM

143

Immunodeficiency linked with a defective tyrosine kinase:

Bruton's X-linked agammaglobulinemia

144

Clinical presentation of a patient with Bruton's X-linked agammaglobulinemia:

6 months into life, child with recurrent bacterial infections. Low B cell count, low Ig of all types.

145

Disorder in which there is no B cell maturation:
Disorder in which B cell maturation becomes defective:

Bruton's X-linked agammaglobulinemia
Common variable immunodeficiency

146

Most common primary immunodeficiency:

Selective IgA deficiency

147

What happens if you give IgA containing blood products to someone with selective IgA deficiency?

Anaphylaxis

148

Immunodeficiency assoc. with 22q11:

DiGeorge

149

IL-12 receptor deficiency leads to a decrease in this type of cell response:

TH1

150

Immunodeficiency associated with tetany:

DiGeorge

151

Suspect this deficiency in a child with disseminated mycobacterial infections:

IL-12 deficiency --> absence of TH1 response

152

T cell disorder in which primary teeth are retained:

Job's syndrome (hyper-IgE)

153

What cytokine is deficient in Job's syndrome?

IFN-g

154

High IgE, eosinophilia, and a failure of neutrophils to deal with business:

Job's syndrome (hyper-IgE)

155

Cold staph abscesses and eczema:

Job's syndrome

156

Defective NADPH oxidase:

CGD

157

Treatment for CGD:

IFN-g
TMP-SMX prophylaxis

158

Truncal eczema is associated with this immune deficiency disease:

Wiskott-Aldrich.

159

Immunodeficiency with high IgA, low IgM, high IgE:

Wiskott-Aldrich

160

This immune deficiency results from a defective adenosine deaminase enzyme:

SCID

161

Absence of thymic shadow, T cells, and germinal centers is associated with which immune deficiency? What are the two most common causal genetic defects?

SCID
IL-2 receptor malformed
Adenosine deaminase deficiency

162

Tyrosine kinase defect is associated with which immune deficiency disorder?

Bruton's agammaglobulinemia

163

Severe pyogenic infections early in life in the presence of both B and T cells are associated with which immune deficiency?

Hyper IgM

164

Immune deficiency with elevated AFP:

Ataxia-telangiectasia.

165

Immune deficiency in which the only intact part of the immune system is NK cells:

SCID

166

Mode of inheritence for CGD:

X-linked

167

Immune deficiency disease where you would see neutrophils filled with giant granules:

Chediak-Higashi

168

Cerebellar defects and immune deficiency, what disease am I? What would you see on labs?

Ataxia-telangiectasia. See high AFP, low IgA and T lymphs.

169

Albinism and problems with infections, what disease am I?

Chediak-Higashi

170

I am a child with recurrent staph and strep infections and peripheral neuropathy. What is my gene defect? Mode of inheritence for my disorder?

LYST = problem with phagosome / lysosome fusion. Autosomal recessive. This is Chediak-Higashi.

171

Immune deficiency in which you would be susceptible to infection by S. aureus, E. coli, Aspergillus, Klebsiella, and Candida:

CGD.
You have no respiratory burst, can still make H2O2, but can't kill catalase (+) organisms.

172

Immune disease associated with the triad of thrombocytopenia, eczema, and infections:
What's the other one where you are likely to see eczema?

Wiskott-Aldrich
WAITER mnemonic
Job's, Hyper IgE

173

You see spider angiomas in a 5-year-old child with poor visual smooth pursuit. Before you put them in front of an X-ray film, stop! Suspect this immunodeficiency:

Ataxia telangiectasia.

174

I am an immunodeficiency associated with neutrophilia. What protein is defective?

Leukocyte adhesion deficiency.
CD18 = LFA-1 integrin defect.

175

In a child with delayed separation of the umbilical cord, suspect:

Leukocyte adhesion deficiency

176

Langerhans cell histiocytosis -- dendritic cell would have this characteristic inclusion:

Birbeck granule, shaped like a tennis racket

177

What molecules are on the surface of a dendritic cell that is prepared to present antigen?

MHC I / II
CD80 / 86
CD40 (expressed by all APC)

178

Which cytokines inhibit T cells?

IFN-g inhibits TH2 cells
IL-10 inhibits TH1 cells

179

Macrophages produce three important acute-phase cytokines:

IL-1
IL-6
TNF-a

180

What is a degmacyte?

A bite cell, an RBC a macrophage has chomped to get at something inside it (ex denatured Hb).

181

Why are people with asplenia prone to thrombocytosis?

Spleen sequesters platelets.
Platelets with no home are in the circulation -> thrombocytosis.