IMMUNOLOGY for step 1

1. IMMUNOLOGY for step 1 Lauren Meshkov, MS-3 lmeshkov@med.miami.edu

2. Tips Memorize non-deducible info Predict board-style?’s (2-3 step thinking) Make connections between subjects Who cares about other people!

3. Overview • Immune organs • Immune cell relationships • Hypersensitivity and Transplant Rejection • Immune deficiencies • Lists to memorize • Questions

4. Immune Organs Bone Marrow Thymus Lymph Nodes • B cells, T cells • T cell maturation • Follicle – B cells • CD4 CD8 +/- selection • Paracortex – T cells (viral enlargement) • 3rdbranchial pouch* • Medulla – Macs, plasma cells • DiGeorge Syndrome** Spleen • Missing spleen? (sicklers, MVA) • Can’t remove… • Encapsulated bacteria SHiNS • (Must give pneumovax!) • Dead RBCs Howell Jolly, Target • Platelets Thrombocytosis • Also Less IgM infection • Fenestrated BM • White Pulp (IgM), Red Pulp (macs), PALS (T cells) • Macs remove encapsulated bacteria ***

5. Immune cell relationships Th1 CD8 CD4 Th2  B cell (1) CD4 x (MHC)2 = 8 CD8 x (MHC)1 = 8 If bacterial (1) 7 1 CD14  LPS endotoxin 5 CD40 6 (Th1) 4 2 3 B7-CD28 Hot T-Bone Steak IL-1 fever IL-2 T cells IL-3 Bone marrow IL-4 IgE IL-5 IgA 7 6 (Th2) 5 CD3 5

6. Hypersensitivity • Type II Antibody mediated • MOA: IgM orIgG vs.self • Result: PMN’s, complement • i.e. hemolytic or pernicious anemia, erythroblastosis, Grave’s, Goodpasture’s, myasthenia gravis, pemphigusvulgaris Type I Anaphylactic, Atopic MOA: IgEon mast cells Result: Vasoactive histamine release i.e. Bee sting, allergies, eczema, asthma, hives (Fast rxns) • Type III Immune Complex • MOA: IgG-Ag deposition* • Result: PMN’s, complement i.e. SLE, RA, polyarteritisnodosa, post strep GN, serum sickness (vasculitides) • Type IV Delayed • MOA: Pre-sensitized T cells • Result: Lymphokines i.e. PPD, TP rejection, poison ivy, contact dermatitis (no Abs!!!)

8. On your own time… • High Yield Lists to Memorize: • Cytokines (“hot T-bone steak”) • Cell surface markers (CD-#) • Complement deficiencies • GranulomatousDiseases • Autoantibodies and associated disorder • Live vs. Killed Vaccines

9. Question 1 • An infant boy with tetany, a heart malformation, and no thymic shadow on CXR presents with recurrent upper respiratory infections. What change would you expect inhislymph nodes? • Enlarged medulla • Enlarged paracortex • Enlarged follicles • Shrunken medulla • Shrunken paracortex • Shrunken follicles • No change

10. Question 2 • A 36 yo male is brought to the ED after a serious MVA with a ruptured spleen. His HR is 150, BP 90/50, RR 25. What is the next best step in his management? • CT scan of abdomen • X-ray of chest and abdomen • Administer pneumovax • IV fluids • Blood transfusion • Splenectomy

11. Question 3 • Natural Killer cells can be identified by which of the following cell surface marker/s? • CD-3 • CD-19 • CD-19, CD-20 • CD-14, CD-16 • CD 16, CD-56 • CD-40, B-7 • CD-28

12. Question 4 • A 9 yo female presents at the clinic with areas of raised linear erythema and pruritis across her lower extremities. She has no other PMH. What is she currently suffering from? • Hypersensitivityrxn Type I • Hypersensitivityrxn Type II • Hypersensitivityrxn Type III • Hypersensitivity rxnType IV

13. Question 5 • A 46 yo female from Mexico has psoriatic arthritis and is about to be treated with Etanercept (anti-TNF-alpha). Which test should you perform before treating this patient? • PPD • Bone scan • Cholesterol levels • HIV test • Liver Function Test • BUN/Creatinine

14. Question 6 • A 20 day-old male infant is brought to the pediatrician’s office for his regular check-up. You note that his umbilical stump has not yet separated. What is the likely cause? • Adenosine deaminase deficiency • LFA-1 integrin deficiency • Defect in microtubule function • Defect in Tyrosine Kinase function • IL-12 receptor deficiency • IFN-gamma deficiency

15. Question 7 • A 21 yoF with fever, headache, and fatigue is admitted to the hospital with septicemia. Her temp is 100.4, HR 120, RR 22, BP 100/60. Labs show WBC 14,000 with 11% bands and deficiency in complement proteins, C5-C8. Which organism is the most likely pathogen? • Group B Strep • Listeria • E.Coli • Strep pneumo • Neisseria • H. influenza • Herpes virus • Enterovirus

16. Question 8 • All of the following contribute to antibody diversity except: • Random recombination of VJ light chains • Random combination of heavy chains with light chains • Random recombination of Fab and Fc fragments • Somatic hypermutation after Ag stimulation • Addition of nucleotides to DNA during recombination

17. Question 9 • A 49 yo female is found to have Anti-Ro (Anti-SSA) and Anti-La (Anti-SSB) antibodies. She will most likely suffer which of set of symptoms? • Xerophthalmia, Xerostomia, Arthritis • Edema, Hematuria, Hypertension • Eczema, Asthma, Conjunctivitis • Ataxia, Spider Angiomas, Sinus infection • Jaundice, Hepatosplenomegaly, Diarrhea

18. Question 10 • A 10-month old infant is diagnosed with an immune deficiency after multiple bouts of infections and recurrent dermatitis. Lab work shows WBC 10,000, Hbg 12, Hct 35, and platelet count 50. What is the inheritence pattern of this disease? • Autosomal dominant • Autosomal recessive • X-linked dominant • X-linked recessive