First Aid Immunology/ Psychiatry Flashcards
3 main features of Wiskott-Aldrich Syndrome
X-linked recessive
WATER: Wiskott-Aldrich
Thrombocytopenia (20-50k) => easy bruising, petechiae, purpura, epistaxis
Eczema
Recurrent infection
Effect of C1 esterase deficiency
Hereditary angioedema b/c allows activation of something that causes huge bradykinin release
-ACEi are contraindicated in these pts
Name two negative acute phase reactants (downregulated by inflammation)
Serum proteins whose concentrations decrease in response to inflammation
- albumin: decrease production to conserve amino acids for the positive reactants (ex: CRP, ferritin, hepcidin, fibrinogen)
- transferrin: internalized by macrophages to sequester iron intracellularly
Which antibodies are involved in each of the 4 types of hypersensitivity reactions
ACID
Type I: Atopy and anaphylaxis (IgE)
Type II: Cytotoxic (IgG and IgM)
Type III: Immune complex (IgG)
Type IV: delayed
Type IV is the only one that doesn’t use antibodies (cell mediated)
Which exposures have preformed antibodies that can be given to unvaccinated patients?
“To Be Healed Very Rapidly”
- tetanus
- botulinum
- HBV
- Varicella
- Rabies
Given passive immunity
Name two inhibitors/checks on the complement pathway
- Cd55 = DAF = decay-accelerating factor
- C1 esterase inhibitor
Both work to inhibit complement activation to reduce: response to self-cells and spontaneous activation
Give a clinical use of the following recombinant cytokines
(a) IFN-alpha
(b) IFN-beta
(c) IFN-gamma
(d) erythropoietin
(a) IFN-alpha used in chronic Hep B/C, Kaposi sarcoma
(b) IFN-beta in multiple sclerosis
(c) IFN-gamma in chronic granulomatous disease
(d) Erythropoietin in anemia (esp in renal failure)
Differentiate what innate and adaptive immunity use for pathogen recognition
Innate immunity uses toll-like receptors that recognize patterns associated w/ pathogens
Adaptive immunity use memory cells whereby first exposure produces a stronger and quicker immune response the next time
3 yo w/ recurrent severe ear infxn
- multiple telangiectasias on face
- walks w/ difficulty, truncal instability
Dx
Dx = ataxia-telangectasia = primary immunodeficiency of both B and T cells 2/2 mutation in ATM gene (DNA repair enzyme)
A’s:
- Ataxia (2/2 cerebellar atrophy)
- IgA deficiency => recurrent sinopulmonary infxn
- Spider Angiomata
- ATM gene mutation
Chronic granulomatous disease
(a) Pathophysiology
(b) Increased risk of what infections
Chronic granulomatous disease
(a) Variety of congenital diseases w/ defective phagocytic NADPH (used to make ROS) => inability to kill certain ingested pathogens
(b) Increased risk of catalase positive species (ex: S. aureus, pseudomonas) and fungi (Aspergillus)
7 yo pt s/p MVA receives blood transfusion to which she develops SOB and oral-facial swelling
- wheezing on exam and atopic dermatitis
- Hx: recurrent ear and lung infection
Dx
Dx = Selective IgA deficiency
- anaphylaxis in response to products containing IgA
- recurrent infection (specifically upper respiratory)
Risk of live attenuated vaccine
Reversion to virulent form
What type of hypersensitivity rxn is
(a) Hyperacute transplant rejection
(b) Graft-vs-host disease
(a) Hyperacute transplant rejection (within minutes) is a type I hypersensitivity rxn 2/2 preformed antibodies
(b) Graft-vs-host is a delayed cellular response = type IV hypersensitivity
Where do the following mature
(a) T cells
(b) B cells
(a) T cells mature in the thymus
(b) B cells mature in the bone marrow
Define acute phase reactant
(a) Induced by what?
(b) Location of production
Acute phase reactant is a serum protein whose concentration changes significantly in response to inflammation
(a) Induced by IL-6
(b) All produced by the liver
Which of the following type of hypersensitivity reaction is responsible for the following
(a) Graves disease
(b) Arthus rxn to tetanus vaccine
(c) Pernicious anemia
(d) SLE
(e) Poison ivy
(f) Graft vs. host
(g) Goodpasture syndrome
Hypersensitivities
(a) Graves- type II (direct cytotoxic)
(b) Arthus rxn to tetanus vaccine is type III (immune complex mediated)
(c) Pernicious anemia- type II
(d) SLE type III
(e) Poison ivy = contact dermatitis = type IV (cellular, delayed)
- not atopic!! be careful
(f) Graft vs. host- type IV (delayed, cellular)
(g) Goodpastures- cytotoxic type II
Describe how DAF deficiency causes paroxysmal nocturnal hemoglobinuria
CD55 (DAF = decay-acclerating factor) is a factor that works to inhibit complement activation to self cells, w/ CD55 deficiency you get complement-mediated breakdown of RBCs => paroxysmal nocturnal hemoglobinuria
Main fxn of interferon alpha and beta
(a) Secreted by what?
Interferon alpha and beta are secreted by virally infected cells to act locally on uninfected cells
Basically work against viral infections
-cause apoptosis locally to disrupt viral amplification
Name the d/o associated w/ the following autoantibodies
(a) Anti-basement membrane
(b) Antiparietal cell
(c) Antimitochondrial
(d) Anti-smooth muscle
(e) Anti-SSA/SSB
Autoantibodies
(a) Anti-basement membrane = Goodpastures
(b) Antiparietal = Pernicious anemia
(c) Primary biliary cirrhosis (PBC)
(d) Antimitochondrial = autoimmune hepatitis
(e) Anti-SSA/SSB = Sjogrens
3 mo old referred for recurrent sinopulmonary infection, flow cytometry shows decrease in CD40L
(a) Dx
(b) Antibody profile expected
(a) HyperIgM Syndrome
- lack of CD40L causes inability to class switch
- p/w severe pyogenic infections early in life
(b) High IgM w/ very low IgG, IgA, and IgE
What two molecules are the primary opsonins of the complement system
Primary opsonins = C3b (binds bacteria directly) and IgG
-work to enhance phagocytosis
Fungal/parasitic infxn seen in dif immunodeficiencies
(a) T cell d/o
(b) B cell d/o
(c) Granulocyte d/o
(a) See local candida and PCP w/ reduced T cells
(b) GI giardiasis w/ B cell d/o (ex: recurrent GI infxn in selective IgA deficiency)
(c) Granulocyte d/o => systemic candida, aspergillus
X-linked agammaglobulinemia
a) Differentiate from selective IgA deficiency
(b) Differentiate from common variable immunodeficiency (CVID
B cell disorders
(a) X-linked agammaglobulinemia will show reduced serum levels of all Ig classes, while selective IgA deficiency will have low IgA but normal IgE and IgG
(b) X-linked agammaglobulinemia presents earlier (like at 6 mo) while CVID often presents later, CVID has normal number of B cells
- both are defects in B cell maturation
What is anergy?
(a) Importance
Anergy = state of inactivity, immune cell cannot be activated by its antigen
-occurs when exposed to antigen w/o co-stimulatory signal
(a) Mechanism of self tolerance
Which type of hypersensitivity is responsible for acute hemolytic transfusion reaction?
Type II hypersensitivity (cytotoxic) is responsible for ABO incompatibility
-when antigen exposure causes direct cellular destruction by MAC formation and complement degredation or opsonization
Which classes of antibodies provide immunity to the fetus?
IgG crosses the placenta => provides infants w/ passive immunity
IgA is expressed in secretions (saliva, tear,s breast milk) so is responsible for the immunologic benefit of breast feeding
Two structures that drains lymphatics into venous system
Right lymphatic duct drains right side of the body above the diaphragm
Then the thoracic duct drains everything else into the junction of the left subclavian and the internal jugular vein
What occurs in the marginal zone of the spleen btwn the red and white pulp?
Marginal zone contains APCs that present antigens to lymphocytes
X-linked agammaglobulinemia
(a) What is it?
(b) Clinical manifestation- age and symptoms
(c) Serum findings
X-linked agammaglobulinemia
(a) B cell immunodeficiency due to mutation that inhibits B cell mutation
(b) Presents around 6 mo (after passive immunity IgG from mom decreases) w/ recurrent bacterial and enteroviral infections
(c) Absent B cells on peripheral smear, low/no Ig of all classes
- absent/scant lymph nodes
X-linked agammaglobulinemia vs. SCID
Both present in early childhood, basically after 6 mo once maternal IgG passive immunity declines
- X-linked agammaglobulinemia is a B cell d/o => recurrent bacerial and enteroviral infections
- SCID is both B and T cell d/o (b/c w/o T cells you don’t activate B-cells) => recurrent viral, bacterial, fungal, and protoxoa infections.
B-cell deficiencies => bacterial infections vs. T-cell deficiencies => viral and fungal infections
Live attenuated vaccine vs. inactivated vaccine
(a) Injected material
(b) Response induced
(c) Advantage over the other
2 types of vaccines
(a) Live attenuated has lost its pathogenicity but transiently retains capacity to grow in the host, while inactivated is inactivated completely while maintaining epitope on cell surface
(b) Live attenuated induces both cellular and humoral response => strong and often lifelong immunity
(c) Inactivated mainly induces humoral response => weaker response, booster shots often required, but no risk of reverting to virulent form
Cytokine responsible for
(a) Recruiting WBC to site of injury
(b) Vascular leakiness to mediate septic shock
(c) Activate NK cells
(d) Stimulate macrophages
(e) Activate bone marrow stem cell growth and differentiation
Important cytokines
(a) TNF-alpha secreted by macrophages recruits WBCs
(b) TNF-alpha secreted by macrophages causes vascular leakiness and mediates septic shock in response to infection
(c) IL-12 from macrophages activate NK cells (feedback response)
(d) Activated NK cells (by IL-12 from macrophages) secrete interferon-gamma to stimulate macrophages to kill phagocytosed pathogens
(e) IL-3 from T cells supports growth and differentiation of bone marrow stem cells
Genetic mechanism of encoding for innate vs. adaptive immunity
Innate immunity encoded by germline
Adaptive immunity (T and B cells) produced by variation using VDJ recombination during lymphocyte development
Differentiate opportunistic viral infections seen in T cell vs. B cell deficiencies
T-cell deficiency => increased risk of CMV, EBV, JCV, VZV
B-cell deficiency => increased risk of enterovirus (polio, enterovirus, echovirus
Cyclosporine
(a) Mechanism of action
(b) Indication
(c) Toxicity
Cyclosporine = immunosuppressant
(a) Calcineurin inhibitor = inhibits transcription of IL-2 => blocks T-cell activation
(b) Organ transplant rejection ppx, psoriasis, RA
(c) Nephrotoxic
- can’t be used in kidney transplant rejection ppx (use sirolimus instead)
Explain why IL-12 receptor deficiency results in a reduced level of serum IFN-gamma
IL-12 secreted by macrophages to induce differentiation of T cells to Th1 cells, also activated NK cells
Then in turn Th1 cells (once activated) secrete IFN-gamma to stimulate macrophages => w/o IL-12 and Th1 activation there is reduced IFN-gamma release
Which type of hypersensitivity is
(a) rapid
(b) most delayed
(c) suspected in many autoimmune diseases
Hypersensitivity
(a) Type I (anaphylaxis, atopic) is due to IgE preformed antibodies => very rapid response to antigen exposure
(b) Type IV is cell-mediated (no antibodies) so very delayed
(c) Type II and III are suspected in AI d/o (mostly type II except SLE is type III)
Which 2 immunosuppressants are best for kidney transplant rejection ppx
The kidney “sir-vives” w/ “Sir”olimus (Rapamycin)
-also use Daclizumab (IL-2R monoclonal antibody)
-can’t use cyclosporine and tacrolimus b/c they’re nephrotoxic
