Immunodeficiency Part II

Question 1

What are the four symptoms of Di George Syndrome?

Answer 1

CATCH 22
Cardiac anomalies
Abnormal facies
Thymic aplasia
Cleft palate
Hypocalcemia
22nd chromosome is partly deleted

Question 2

What causes hypocalcemia in Di George patients? What symptom results from this, specifically?

Answer 2

No parathyroid means no PTH –> low calcium levels. Tetany is a symptom - shaking of fingers and hands.

Question 3

What organisms/infections are Di George patients susceptible to?

Answer 3

No T cells, so no cell-mediated immunity to protect against intracellular bacteria, fungi, large viruses.
No T cell help for B cell switching, so also at risk for infection by pyogenic organisms.

Question 4

What is the treatment for Di George Syndrome?

Answer 4

Stem cells from Johns Hopkins that have no MHC or umbilical cord cells.

Question 5

Which syndrome is caused by a failure of the mediastinum to develop during fetal development?

Answer 5

Di George Syndrome.

Question 6

Why is severe combined immunodeficiency named so?

Answer 6

Because both humoral and cell-mediated immunity is compromised.

Question 7

What is the most common cause of SCID? What is the mechanism of inheritance?

Answer 7

X-linked SCID is due to an IL-2 receptor gamma (common) chain mutation. 70% of cases.

Question 8

Which part of the immune system is critical for fighting candida: humoral, cell-mediated, or innate?

Answer 8

Cell-mediated (T cells)

Question 9

What is the treatment for x-linked SCID?

Answer 9

Stem cells

Question 10

Name two sources of stem cells that minimize risk for GVHD following bone-marrow transplant.

Answer 10

1. Umbilical cord blood

2. MHC-less stem cells from Johns Hopkins

Question 11

What is the treatment for SCID caused by ADA deficiency?

Answer 11

Enzyme replacement therapy.

Question 12

Name four more forms of SCID other than ADA deficiency and x-linked SCID.

Answer 12

1. Bare lymphocyte syndrome - no MHC I or II
2. Abnormal signal transduction molecules
3. CD3 mutations
4. Defective cytokine production

Question 13

What are RAG1 and RAG2 and how can mutations of these proteins cause SCID?

Answer 13

These proteins are required for VDJ recombination. Without them, T cell receptors are inoperative –> no T cells, no T cell help for B cells.

Question 14

Name two signal transduction molecules that, if mutated, could case SCID.

Answer 14

1. JAK3

2. ZAP70

Question 15

Name the disease given the following:

1. T and B cell deficiency
2. Thrombocytopenia
3. High IgE levels causes eczema

Answer 15

Wiskott Aldridge Syndrome

Question 16

What are the three things we are supposed to know about Ataxia Telangectasia?

Answer 16

1. Ataxia (funny gait)
2. Telangectasia (spider veins)
3. Immunodeficiency

Question 17

Lymphoma and myeloma cause secondary defective _________ immunity.

Answer 17

humoral

Question 18

What part of the immune system is compromised by severe burns?

Answer 18

Humoral - think mucous membrane damage due to deep burns, causing secretory IgA to leak out. B cells make Igs - humoral immune system.

Question 19

Immunosuppressive drugs and malnutrition can cause secondary defective ________ immunity.

Answer 19

cell-mediated.

Question 20

What part of the immune system is most greatly diminished as people age?

Answer 20

Cell-mediated, innate too.

Number and function of neutrophils, APCs, NK cells, and T cells drop.

Question 21

Which specific receptors are involved in HIV binding to a CD4+ cell?

Answer 21

The viral gp120 binds to the CD4+ cell, and then the viral gp41 binds to the CCR5 receptor on the CD4+ cell.

Question 22

What three lab tests are used to determine is a person has HIV?

Answer 22

1. Ab or Ag assay
2. Reversal of CD4:CD8 ratio (normally 2:1)
3. Measure serum HIV RNA

Question 23

IL-17 is important in controlling what type of infections?

Answer 23

Fungal