Test 2 Prep Flashcards
What is the function of FcRn?
Helps bring IgG into to endothelial cells and protects it in endosomes –> releases IgG for recirculation
responsible for taking IgG from mom to fetus
What are the 3 major things that make High-affinity B-cells survive after contacting Tfh cells?
- BCI-2 expression is induced upon Ag recognition –> anti-apoptosis
- CD40L/CD40 signalling w/ Tfh cells –> promotes survival
- Fas inhibitors are activated –> prevent apoptosis
Once IgG coats a microbe, what happens?
What is this process called?
IgG binds Fc receptor on phagocytes
This is opsonization!
What is the Fc receptor is involved in Ag-Ab complexes that can bind the BCR and and FcR at the same time?
What part of the antibody binds this receptor?
FcgammaRIIB
Fc region of Ab
What is the product of something binding to FcgammaRIIB on B cells?
inhibition of B signaling
What is the function of RcepsilonRI?
receptor on eosinophils and mast cells
IgE binds RcepsilonRI –> degranulation and parasite killing
What does B cell deficiency result in?
recurrent bacterial infections
often causing otitis media and pneumonia
What does T cell deficiency result in?
viral, fungal, and protozoal infections
How can multiple myeloma be detected?
will see a large spike in Igs of only one type
What Ab response is still intact in DiGeorge syndrome?
IgM immune response
can’t do isotype switching bc T cell deficient, but IgM ok
If skin allergen skin testing is positive w/in 30 min, what type of sensitivity is shown?
Immediate hypersensitivity
What type of hypersensitivity uses IgG and IgM, but never IgE?
type II hypersensitivity
What are the diseases mentioned that are type III sensitivity?
SLE
serum sickness
arthus reaction
post-streptococcal glomerulonephritis
What are the clinical syndromes associated w/ type I hypersensitivity?
brochial asthma
food allergies
anaphylaxis
What are the clinical syndromes associated w/ type II hypersensitivity?
hemolysis reactions rheumatic fever goodpasture syndrome graves' disease myasthenia gravis
What is the main difference btw type II and type III hypersensitivities?
In type II, your Abs bind your own tissues –> reaction
in type III, your Abs make complexes w/ other stuff –> floats around and causes reactions
What are the clinical syndromes associated w/ type IV hypersensitivity?
contact sensitivity MS type I diabetes TB toxic shock syndrome Crohn's disease
What cytokines are required to isotype switch to IgE?
IL-4
IL-5
What cytokines are required to isotype switch to IgG?
IFN-gamma
What cytokines are required to isotype switch to IgA?
TNF-beta
What type of lymphocytes are in the paracortical areas of lymph nodes?
B cells
What form does the ag need to be in for type IV hypersensitivity?
protein form
bc T cell dependent
What part of an IgM antibody binds with complement?
the Fc region
If Th17 cells are overexpressed, what IL is most likely inhibited?
IL-23
produced by macrophages to activate
What cytokine induces PD-1 expression in T cells?
INF gamma
What transcription factor helps make perforin and granzymes in CTL cells?
Tbet
What do IL-7 and IL-15 do?
induce anti-apoptotic genes that memory T cells
What chemokine do follicular DCs release to attract B cells to the follicle?
CXCL13
People with what type of t cell deficiency causes the worse version of leprosy (lepromatous)?
th1 deficiency (or Th2 dominanty immune system)
What does retinoic acid do?
TGF beta and IL-2 with retinoic acid –> Treg
inhibits
