Immunology- FA Flashcards
List three opsonins
C3b
IgG
CRP
*C3b and IgG are main opsonins
Cutaneous Candida vs. systemic Candida. which blood cells are associated with each?
cutaneous: T cells
systemic: Granulocytes
Which lymphocyte is associated with GI giardiasis?
B cell (IgA)
Which cytokine is involved in cachexia (muscle wasting) in malignancy?
TNF-alpha
Which immunosuppressant has nephrotoxicity as a major side effect?
calcineurin inhibitors
cyclosporin and tacrolimus
In the spleen, where do APCs capture blood-borne antigens for recognition by lymphocytes
marginal zone, between red pulp and white pulp
- white pulp: B cells, PALS: T cells
- Red cells: APCs flowing in spleen
- in between: marginal zone- APC presents antigens to B/T cells
Which structural region of the antibody determines the isotype?
Fc portion
- isotype: Different classes (IgM, IgG,..)
Which structural region of the antibody determines the idiotype?
Fab
*idiotype: only one unique/specific antigen-binding pocket for antigen
Which cytokine functions to drive differentiation of helper T cells into Th1 cells?
IL-12
Which cytokine functions to drive differentiation of helper T cells into Th2 cells?
IL-4
Which cytokine functions to drive differentiation of helper T cells into Th17 cells?
IL-6, TGF-beta
Which immune cell expresses FOXP3?
regulatory T cell
In what way does Neisseria gonorrhoeae exhibit antigenic variation?
pilus protein variation
Which cells produce and secrete interferon-α and -β?
virally infected cells
interferon-α and -β are glycoprotein
- > released by virally infected cells
- > act locally on UNINFECTED CELLS
- > degrade viral DNA and RNA
Why is live attenuated vaccine contraindicated in pregnant and immunocompromised pts?
it can revert back to virulent form
they are live!
Gram-negative bacteria release endotoxins/LPS that directly stimulate macrophages. Which receptors mediate this process?
CD14 (TLR4)
receptor on macrophages. Th cells are NOT involved
Two acute phase reactants that are decreased in inflammation?
- transferrin: to prevent iron loss from bacteria
more transferrin, more iron available in serum - albumin: to increase synthesis of other proteins
Which two signals induce natural killer cell killing activity?
- nonspecific activation signal on target cell
- absence of MHC1: NK cells are responsible for killing tumor cells. Tumor cells evade T cell mediated immune response as it lacks MHC1.
What is the only one live attenuated vaccine that can be given to HIV?
MMR
Which five diseases can be treated with passive immunity?
Tetanus Botulism HBV Varicella Rabies
To Be Healed Very Rapidly
C3 deficiency causes increased risk for what type of hypersensitivity reaction? why?
type 3
C3b (opsonin) helps clearing immune complex
What are thymus independent antigen?
non-peptide antigen (lipopolysaccharides from gram negative bacteria)
T cells only recognize peptide as antigen
Which complements (3) are involved in anaphylaxis?
C3a, C4a, C5a
- C5a also plays role in neutrophil chemotaxis
Which cytokine can be used to treat multiple sclerosis?
IFN-beta
pernicious anemia: what HLA?
HLA-DR5
Name and target of the antibody that would you give to prevent RSV infection?
palivizumab, targets RSV F protein (fusion protein)
What immunosuppresent causes hirsutism and gingival hyperplasia
cyclosporine
- note that major toxicity of cyclosporine is nephrotoxicity
- another calcineurin inhibitor, tacrolimus, does NOT have hirsutism and gingival hyperplasia
IL-6
- secreted by what cell?
- function?
- macrophage releases IL-6
- production of acute phase reactants
IL-8
- secreted by what cell?
- function?
- macrophage
- neutrophil chemotaxis
Multiple sclerosis is what type of hypersensitivity reaction?
type 4
Which two enzymes in respiratory burst require selenium as cofactor
glutathione reductase
glutathione peroxidase
A patient with a bacterial infection coughs up blue-green sputum. What is the function of the enzyme giving this sputum its color?
myeloperoxidase
final step of respiratory burst: H2O2 -> HOCl (bleach)
Where are complement proteins made?
liver
What is composition of MAC (Membrane Attack Complex)?
C5b-C9
cyclosporine vs. tacrolimus: MOA?
cyclosporine: binds cyclophilin and inhibits calcineurin, preventing IL-2 transcription and blocking T-cell activation
tacrolimus: binds FKBP to inhibis calcineurin
- BOTH are calcineurin inhibitors.
- BOTH are nephrotoxic
Blood transfusion reaction: allergic vs. anaphlylatic
- symptoms
- treatment
allergic
- urticaria, pruritus, wheezing, fever
- treat with anti-histamine
anaphlylatic
- shock, hypotension, bronchospasm
- treat with epinephrine
- maintain BP is the first thing to do. hypotension due to shock-> needs epinephrine to increase BP
What is function of regulatory T cells?
immune tolerance by suppressing CD4 and CD8 T cells
What two CD markers are associated with IL-2 signaling pathway?
CD3 and CD4
target of infliximab? indications?
TNF- alpha
IBD, RA
target of aldesleukin? indications (2)?
IL-2
RCC, metastatic melanoma
Mechanism in which TSS-1 toxin of S.aureus produces superantigen?
crosslinks MHC2 and TCR
-> polyclonal activation and expansion of CD4+ T cells
: it activates massive amount of random CD4+ T cells
Apart from inducing fever, what is another function of IL-1?
activation of osteoclast activity
- IL-1 is called osteoclast activating factor
Most abundant antibody?
IgG
Which cell surface proteins (2) are unique to regulatory T cells?
CD4 and CD25
Which cytokine can be used to treat chronic granulomatous disease (CGD)?
IFN-gamma
Hemochromatosis: what HLA?
HLA-A3
Anaphylaxis: mediators?
- actue
- delayed
- acute: IgE cross-linking on mast cells
- delayed: leukotrienes
Which cell surface protein on NK cells bind to the Fc region of IgG?
CD16
Unique cell surface protein on NK cells?
CD56
Disseminated mycobacterial infections after receiving the BCG vaccine: diagnosis? inheritance pattern?
IL-12 receptor deficiency: impaired Th1 cell activation
autosomal recessive
What cells express MHC1?
all cells except RBC (no nucleus)
- remember: MHC1 presents ENDOGENOUSLY expressed VIRAL protein (viral DNA inserted to genome)
anuecleated cells will NOT express viral protein. so no MHC1
SLE: what HLA? (2)
HLA-DR2 and DR3
Sirolimus: side effects? (3)
- pancytopenia
- SIROlimus, panSIRtopenia
- hyperlipidemia
- insulin resistance
Serum sickness vs. Arthus reaction: similarities and difference?
BOTH are type 3 hypersensitivity reaction, fix complements
- Serum sickness is immune complex deposition with SYSTEMATIC symptoms: fever, urticaria, lymphadenopathy
- Arthus is LOCAL SUBACUTE immune complex deposition
: classic example is subacute edema and necrosis after intradermal injection of antigen
PSGN: what type of hypersensitivity?
type 3
Hyper-IgE syndrome (Job syndrome)
- inheritance pattern
- etiology
- autosomal dominant
- only AD disease in immunodeficiency
- most others are either XR or AR
- STAT3 mutation -> loss of Th17 cells
Daclizumab: MOA? what is another drug that has same MOA?
monoclonal antibodies agains IL-2R
Basiliximab works in same mechanism with Daclizumab
What are anti-inflammatory cytokines? which cell secrets them?
IL-10 and TGF-beta
secreted by regulatory T cell
* this makes sense: regulatory T cells mediate immune tolerance by SUPPRESSING T cell response
septic shock: which cytokine?
TNF-alpha
What are two immunizations that use both passive and active immunity on viral exposure?
HepB and Rabies
CGD: suscptible for what bugs infection?
catalase positive N- nocardia P- pseudomona L- listeria A- aspergillios C- candia E- e.coli S- staph S- serratia H- H.pylori B- B. cepacia
Sirolimus: MOA?
Inhibition of mTOR: Inhibition of IL-2 signal transduction
What is target of eculizumab?
complement protein C5
* eculizumab is indicated for PNH (paroxysmal nocturnal hemoglobinuria)
SCID: two possible defects? inheritance pattern of each? which one is more common?
- defective IL-2R gamma chain, X-linked, most common
- adenosine deaminase deficiency, autosomal recessive
Regulatory T cell: CD markers (2)?
CD4 and CD25