8. Immuno Flashcards
To which lymph nodes do the sigmoid colon and the rectum drain?
sigmoid colon: inf mesenteric
upper rectum: inf mesenteric
lower (to pectinate line): int iliac
lower (below pec line): sup inguinal
In what parts of the lymph nodes would B cells and T cells be located?
B cells: follicles (of the cortex)
T cells: paracortex
Where would you find Peyer’s patches?
ileum (in lamina propria + submucosa)
What molecules are expressed on the surface of antigen-presenting dendritic cells?
- MHC class 1, 2
- B7 protein
- CD40
What 3 cell types are known for presenting antigens to CD4+ T cells?
- dendritic cells
- macrophages
- B cells
What characteristic finding would you see on electron microscopy of a dendritic cell in a pt with Langerhans cell histiocytosis?
Birbeck granules (tennis racket)
Which cytokines are produced by Th1 cells? by Th2 cells?
Th1 = IL-2, IFN-gamma Th2= IL-4, IL-5, IL-10
Which cytokines inhibit Th1 cells? Which inhibit Th2 cells?
Th1 –> IL-10
Th2 –> IFN-gamma
How do cytotoxic T cells kill virus-infected cells and neoplastic cells?
- granzyme B + perforin
2. Fas-ligand on T-cell binds to Fas-receptor on target cell –> induce apoptosis
Which surface markers are found on B-cells?
CD19, 20, 21 IgM, IgD MHC class I, 2 B7 protein CD40
What immunoglobulin is associated with allergies b/c it is bound by mast cells and basophils and causes them to degranulate and release their histamine?
IgE
What immunoglobulin comprises 70-75% of the total immunoglobulin pool?
IgG
What immunoglobulin is present in large quantities on the surface of many B cells?
IgD, IgM
What immunoglobulin crosses the placenta and additionally confers immunity to neonates in the first few months of life?
IgG
What immunoglobulin can occur as a dimer?
IgA (secretory)
What immunoglobulin is largely confined to the intravascular pool and is the predominant early antibody frequently seen in the immune response to infectious organisms with complex antigens?
IgM
What immunoglobulin is distributed evenly b/w the intravascular and extravascular pools?
IgG
What immunoglobulin is the predominant immunoglobulin in mucoserous secretions such as saliva, colostrum, milk, tracheobronchial secretions, and GU secretions?
IgA
What immunoglobulin can be a pentamer?
IgM
What initiates recombination of V(D)J sequences?
RAG-1, RAG-2
–> recombination activating genes
Which viral vaccines are potentially dangerous to pts with an egg allergy? (2)
- influenza
- yellow fever
What autoimmune disease is associated with anti-dsDNA antibodies?
SLE
What stain is used to identify amyloid microscopically, and how is its appearance described?
congo red stain
- apple green birefringence under polarized light
Which type of hypersensitivity is responsible for post-strep GN?
3
Which type of hypersensitivity is responsible for asthma?
1
Which type of hypersensitivity is responsible for rheumatic fever?
2
Which type of hypersensitivity is responsible for tuberculosis skin test (PPD)?
4
Which type of hypersensitivity is responsible for allergies, anaphylaxis, and hay fever?
1
Which type of hypersensitivity is responsible for polyarteritis nodosa (PAN)?
3
Which type of hypersensitivity is responsible for serum sickness?
3
Which type of hypersensitivity is responsible for ABO blood type incompatibility?
2
Which type of hypersensitivity is responsible for poison ivy?
4
Which type of hypersensitivity is responsible for eczema?
1
Which type of hypersensitivity is responsible for contact dermatitis?
4
Which type of hypersensitivity is responsible for Goodpasture syndrome?
2
A patient suffers from recurrent Neisseria infections. What complement proteins are deficient?
C5b - 9
Which complement is responsible for neutrophil chemotaxis?
C5a
What cytokines are produced by Th1 cells?
IL-2, IL-3, IFN-gamma
What cytokines are produced by Th2 cells?
IL-2, IL-3, IL-4, IL-5, IL-10
What cytokines promotes growth and differentiation of B cells?
IL-4, IL-5
What cytokines promotes growth and activation of eosinophils?
IL-5
What cytokines are pyrogens secreted by macrophages?
IL-1, IL-6
What cytokines enhance synthesis of IgE and IgG
IL-4 (remember, BEG 4 it)
What cytokines enhance synthesis of IgA
IL-5
What cytokines mediate inflammation?
IL-1, IL-6, TNF-alpha
What cytokines are secreted by Th1 cells and activate macrophages?
IFN-alpha
What cytokines are secreted by Th2 cells and inhibits macrophage activation?
IL-10
What cytokines inhibits production of Th1 cells?
IL-10
What cytokines inhibits production of Th2 cells?
IFN-gamma
What cytokines are released by virus-infected cells?
IFN-alpha, IFN-beta
What cytokines supports growth and differentiation of bone marrow stem cells?
IL-3
What cytokines supports T-cell proliferation, differentiation, and activation?
IL-2
What is the function of macrophages in the spleen? (2)
- remove encapsulated bacteria
2. remove dysfunctional RBCs
Which immunosuppressant is a precursor of 6-mercaptopurine?
azathioprine
Which immunosuppressant inhibits IMP dehydrogenase?
mycophenolate
Which immunosuppressant inhibits calcineurin resulting in the loss of IL-2 production and inhibition of T-cell differentiation and activation?
cyclosporin
Which immunosuppressant binds FK-binding protein (FKBP) leading to loss of IL-2 production?
tacrolimus
Which immunosuppressant binds FKBP12 leading to inhibition of mTOR and inhibition of T-cell proliferation?
sirolimus (rapamycin)
Which immunosuppressant is used for lupus nephritis?
azathioprine
mycophenolate and cyclosporin used off-label
Which immunosuppressant is metabolized by xanthine oxidase, therefore allopurinol increases its toxicity?
azathioprine
What are the X-linked immunodeficiencies?
WACH
- Wiskott-Aldrich syndrome
- Agammaglobulinemia (Bruton)
- Chronic granulomatous disease (CGD)
- Hyper IgM syndrome
What are the clinical features of Wiskott-Aldrich syndrome?
WAITER
- Wiskott
- Aldrich
- Immunodeficiency
- Thrombocytopenia + purpura
- Eczema
- Recurrent pyogenic infections
- low IgM, high IgA
What is the cause of chronic granulomatous disease (CGD)? To what infections are these individuals susceptible?
- absence of NADPH oxidase
- susceptible to catalase + pathogens (esp. S. aureus, aspergillus)
A young child presents with tetany from hypocalcemia, and candidiasis resulting from immunosuppression. What cell type is deficient in this patient?
T-cell (DiGeorge; thymic aplasia)