Immunology Review Corner

Immunology Review Corner: Chapter 59 of the 6th edition of Middleton’s Allergy Principles and Practice, edited by N. Franklin Adkinson, et al.

Prepared by Dr. Thao N. Tran, Puget Sound Allergy, Asthma and Immunology, and Dr. Karla L. Davis, Walter Reed Medical Center.

Chapter 59:  Primary Immunodeficiency Diseases – Part I

1. Which of the following immunodeficiencies has been mapped to chromosome Xq22?
a. DiGeorge Syndrome
b. X-linked Severe Combined Immunodeficiency (SCID)
c. X-linked Agammaglobulinemia (XLA)
d. Chronic Granulomatous Disease (CGD)

2. XLA patients have which of the following lab abnormalities?
a. Decreased level of circulating natural killer (NK) cells
b. Intermittent neutropenia
c. Normal antibody formation to proteins, but not to polysaccharides
d. Abnormal CD4:CD8 ratio

3. CD40 ligand (or CD154) is found on the surfaces of:
a. Immature B cells
b. Monocytes
c. Mature B cells
d. Activated T cells

4. A 28-month-old boy comes into your office with a history of bloody diarrhea, three episodes of pneumonia, and severe atopic dermatitis. Which of the following lab findings would you expect to see in this patient?
a. Normal percentage of T cells on flow cytometry
b. Normal appearing megakaryocytes with defective platelets
c. Elevated serum IgM
d. Cyclic elevation of blood neutrophils

5. A family has more than one male patient with Common Variable Immunodeficiency (CVID). A mutation in which of the following genes is most likely?
a. Signal Lymphocyte Activation Molecule (SLAM) – Associated Protein (or SH2D1A)
b. Wiskott-Aldrich Syndrome Protein (WASP)
c. Janus Kinase 3 (Jak-3)
d. Nuclear Factor Kappa B Essential Modulator (NEMO)

6. Osteomyelitis with cultures growing out Serratia marcescens is likely to be seen in which of the following immunodeficiencies?
a. X-linked CGD
b. XLA
c. CVID
d. X-linked Immunodeficiency with Hyper-IgM

7. A 6-month-old boy has a history of persistent diarrhea, recurrent cellulitis, Pneumocystis carinii pneumonia, and failure to thrive. Which of the following findings helps support your diagnosis of X-linked SCID?
a. History of absolute lymphocyte count of 3500/mm3 in the cord blood
b. Few or absence of T and NK cells
c. Few or absence of T, B, and NK cells
d. Absolute lymphocyte count of 5000/mm3 in peripheral blood

8. X-linked SCID is a pediatric emergency. Treatment includes:
a. IVIG and thymic transplant
b. HLA-identical or haploidentical bone marrow transplant with pretransplant chemotherapy
c. HLA-identical or haploidentical bone marrow transplant without pretransplant chemotherapy
d. Interferon gamma infusion

9. Which of the following best describes the molecular basis for Adenosine Deaminase (ADA) Deficiency?
a. Absence of ADA results in failure of B cells to undergo somatic hypermutation
b. Absence of ADA results in failure to form antigen receptors in both B and T cells
c. Absence of ADA results in excessive inactivation of S-adenosylhomocysteine which leads to uncontrolled cellular methylation reactions
d. Absence of ADA leads to pronounced accumulation of adenosine and its metabolites, resulting in apoptosis of thymocytes and circulating lymphocytes

10. Which of the following forms of autosomal recessive SCID has lymphocyte characteristics that resemble those of patients with X-linked SCID, including elevated percentage of B cells and very low percentages of T and NK cells?
a. ADA Deficiency
b. Jak 3 Deficiency
c. Recombinase Activating Gene (RAG) Deficiency
d. Interleukin-7 Receptor Alpha-Chain (IL-7alpha) Deficiency

11. Patients with which of the following forms of SCID have increased radiation sensitivity?
a. Jak 3 Deficiency
b. Artemis Gene Product Deficiency
c. CD45 Deficiency
d. IL-7alpha Deficiency

12. Which of the following lab findings is seen in a patient with MHC Class I deficiency?
a. Low Beta2-microglobulin
b. Low CD8+ and CD4+ T cells
c. Mutation of the gene that encodes the peptide transporter protein
d. Absence of HLA-DP, DQ, and DR on monocytes

Answers
1. c, pg. 1017
2. b, pg. 1018
3. d, pg. 1019
4. b, pg. 1020
5. a, pg. 1021
6. a, pg. 1021
7. b, pg. 1022-1023
8. c, pg. 1023
9. d, pg. 1024
10. b, pg. 1024
11. b, pg. 1025
12. c, pg. 1026-1027