Immunodeficiency Part I

Question 1

Neutrophils are crucial for _________ immunity.

Answer 1

innate

Question 2

Name three things that attact neutrophils and where they come from.

Answer 2

1. Chemotactic cytokines from APCs
2. C3a from complement binding (classical or mannose)
3. C5a from complement binding (classical or mannose)

Question 3

What is neutropenia?

Answer 3

Inadequate numbers of neutrophils (example: chemotherapy)

Question 4

What effector response involving neutrophils would be affected if someone had either IgG or C3b deficiency?

Answer 4

Opsonization

Question 5

What is Chronic Granulomatous Disease (CGD)?

Answer 5

Inability to generate superoxide anions due to a defect in cytochrome b and NADPH oxidase. Organisms are eaten by neutrophils, but lysosomal granules are not able to kill them. X-linked

Question 6

What is Leukocyte Adhesion Deficiency (LFA-1 deficiency)?

Answer 6

Lack of LFA-1, an endothelial cell adhesion molecule. Result is failure of neutrophils to emigrate out of vessels toward an antigen, failure of CD8+ cells to bind targets, and recurrent bacterial infection. Also, failure to heal wounds.

Question 7

What is the diagnosis if a newborn has delayed umbilical cord separation (umbilicus)?

Answer 7

Leukocyte adhesion deficiency (LFA-1 deficiency)

Question 8

Which disease is characterized by the fusion of lysosomal granules in neutrophils and recurrent infection?

Answer 8

Chediak Higashi Syndrome.

Question 9

What is Bruton’s Agammaglobulinemia?

Answer 9

No mature B cells in the blood (pre B cells are in the marrow, though). Therefore, no IgG, IgA, IgM, or IgE. Absent/small tonsils and lymph nodes.

Question 10

What is the root cause of X-linked Bruton’s Agammaglobulinemia?

Answer 10

Mutation of the Btk gene that is important for antibody light chain rearrangement.

Question 11

Is IgA deficiency common? Is it often symptomatic?

Answer 11

Yes, common (1:700). Usually not symptomatic.

Question 12

What typically presents when a person has IgA deficiency coupled with IgG2 or IgG4 deficiency?

Answer 12

They develop severe respiratory and GI infections.

Question 13

What is the treatment for IgA deficiency?

Answer 13

No known Tx.

Question 14

What can cause Hyper IgM syndrome?

Answer 14

CD40 ligand or CD40 mutations, or AID deficiency. All are required for isotype switching of B cells.

Question 15

What is transient hypoagammaglobulinemia of childhood?

Answer 15

Delay in Ab production. B cells present, cause unknown.

Question 16

What is common variable immunodeficiency?

Answer 16

Low serum levels of all Igs that suddenly appears in adulthood. Increased susceptibility to infections. B cells are present but there is a problem with plasma cell differentiation.

Question 17

What is the treatment for common variable immunodeficiency?

Answer 17

IVIG