Immunology

Question 1

What causes leukocyte adhesion deficiency?

Answer 1

Autosomal recessive disorder characterized by absence of CD18 antigens necessary for the formation of integrins, leukocyte adhesion, and migration

Question 2

What are the clinical features of leukocyte adhesion deficiency?

Answer 2

Recurrent skin and mucosal infections without purulence, delayed separation of the umbilical cord, and persistent leukocytosis

Question 3

What receptor enables HIV entry into cells?

Answer 3

CCR5

Question 4

CD14

Answer 4

Surface marker for monocyte-macrophage cell lineage

Question 5

Which cells recognize and kills cells with decreased MHC class I antigen cell surface expression?

Answer 5

NK cells

Question 6

What mediates the destruction in the process of apoptosis?

Answer 6

Caspases - proteolytic enzymes that cleave cellular proteins

Question 7

Chronic inflammation is associated with increased circulation of which cytokines?

Answer 7

Pro-inflammatory cytokines IL-1, IL-6, tumor necrosis factor alpha

Question 8

What are the acute-phase reactants released from the liver

Answer 8

C-reactive protein, fibringogen

Question 9

Chronic granulomatous disease

Answer 9

Commonly due to X-linked mutation affecting NADPH oxidase. Leads to an inability of neutrophils to form the oxidative burst.

Question 10

How is CGD diagnosed?

Answer 10

By the absence of the normal blue and fluorescent green pigment produced by the nitroblue tetrazolium test and dihydrorhodamine flow cytometry test

Question 11

Graft versus host disease

Answer 11

T lymphocytes found in the donor organ become sensitized against the MHC antigens of the recipient and attack the host’s tissues. Skin, liver, and GI tract are most frequently affected

Question 12

Recurrent sinopulmonary and GI infections as well as autoimmune disease. Can have anaphylaxis during transfusion of blood products

Answer 12

Selective IgA deficiency

Question 13

What inherited defect results in disseminated mycobacterial disease in infancy or early childhood?

Answer 13

Defects involving the interferon-gamma signaling pathway. Pts require lifelong treatment with antimycobacterial agents

Question 14

Rubella

Answer 14

Unvaccinated child. Togavirus, maculopapular rash that begins on the face and spreads to the trunk and extremities, postauricular and occipital lymphadenopathy

Question 15

What enhances the activity of NK Cells

Answer 15

IL-2, IL-12, IFN-alpha, IFN-beta

Question 16

Th1 Cell (secretes, fxn, induced by, inhibited by)

Answer 16

IFN-gamma
Activates macrophages and cytotoxic T cells to kill
IFN-gamma, IL-12
IL-4, IL-10

Question 17

Th2 Cell (secretes, fxn, induced by, inhibited by)

Answer 17

IL-4, IL-5, IL-6, IL-10, IL-13
Activates eosinophils, promotes prod. of IgE
IL-2, IL-4
IFN-gamma

Question 18

TH17 Cells (secretes, fxn, induced by, inhibited by)

Answer 18

IL-17, IL-21, IL-22
Immunity against extracellular microbes, induce inflamm.
TGF-beta, IL-1, IL-6
IFN-gamma, IL-4

Question 19

Treg Cells (secretes, fxn, induced by, inhibited by)

Answer 19

TGF-beta, IL-10, IL-35
Prevent autoimmunity
TGF-beta, IL-2
IL-6

Question 20

IL-8

Answer 20

Secreted by macrophages. Major chemotactic factor for neutrophils

Question 21

IL-12

Answer 21

Secreted by macrophages. Induces differentiation of T cells into Th1 cells
Activates NK cells

Question 22

TNF-alpha

Answer 22

Secreted by macrophages. Activates endothelium. Causes WBC recruitment, vascular leak

Question 23

IL-4

Answer 23

Enhances class switching of IgE and IgG

Question 24

IL-5

Answer 24

Enhances class switching of IgA

Question 25

List the encapsulated organisms

Answer 25

Pseudomonas, Streptococcus, Haemophilus Influenza type b, Neisseria, E. coli, Salmonella, Klebsiella, Group B strep

Question 26

What are the critical cytokines for the formation and maintenance of granulomas?

Answer 26

TNF-alpha, IFN-gamma, and IL-12

Question 27

Most important mediator of sepsis?

Answer 27

Tumor necrosis factor alpha

Question 28

Antibodies present in pt with polymyositis

Answer 28

Antinuclear and anti-Jo-1 autoantibodies