Immunology Flashcards
What type of hypersensitivity is IMHA?
What antibody is the pain player in each intravascular and extravascular hemolysis?
Type III hypersensitivity
Intravascular: IgM (or IgG)
Extravascular: IgG
How neurtophils kill bacteria via oxidative burst? (explain the cascade/steps)
- Bacteria are phagocytized
- with NADPH & O2, superoxide anion is formed
- Hydrogen peroxide
- Hypochloric acid
- Kill bacteria
- Lysozymes & defense’s acid hydrolase digests bacteria after their death
Th2 stimulated by ___, ___
IL-4, IL-1
Th1 stimulated by ___, ___
IL-12, IL-2
Ig which does cross placenta
IgG crosses placenta
IgA does NOT cross placenta, does NOT activated complement
(IgA is a dimer, IgM is a pentamer, IgG is a monomer)
What is the APC cells in the skin?
Langerhans cells
Pemphigus folliaceous
- Common skin lesion affected
- What is the target of antibodies
- Face (not mucosal; only epidermal desmosomes are affected)
- Desmoglein 1
What factor inhibits complement C3b?
Factor I
What is the mediators involved and examples in type I hypersensitivity?
Type I: Allergy, immediate
Examples: anaphylaxis, asthma, atopy, vaccine reaction
Mediators: IgE, Th2 type cytokines, histamine, leukotrienes, PGs, PAR
What is the mediators involved and mediators in type II hypersensitivity?
Type II: cytotoxic, antibody-dependent
Examples: IMHA, ITP, pemphigus, transfusion reaction
Mediators: IgG, IgM
What is the mediators involved and mediators in type III hypersensitivity?
Type III: immune complex disease, Ab-Ag complexes deposited
Examples: SLE, Lyme nephritis, rheumatoid arthritis
Mediators: aggregation of antigens, IgG, IgM, complement proteins
What is the mediators involved and mediators in type IV hypersensitivity?
Type IV: delayed reaction, delayed hypersensitivity, cell-mediated, antibody independent
Examples: contact dermatitis, tuberculosis, chronic transplant rejection
Mediators: T cells, monocytes, macrophages
Defensins
Alpha granules of neutrophils
Cause collapse of cholesterol free bacterial cell membranes
What is a necessary step in intravascular hemolysis?
Complement activation by classical pathway (antigen-antibody complexes)
Which receptor on the cell surface recognizes LPS?
TLR4
What type of vaccine that causes Th1 responses?
Live, modified lice, viral and DNA vaccines
Vaccines that stimulate cell-mediated immunity
Eosinophilic bronchopneumopathy (EBP) is characterized by eosinophilic infiltration and is dominated by CD4+ T cells. What type of immune response is involved in EBP?
Th2 response
What is the most potent inducer/activator of tumor cell destruction by NK cells and cytotoxic T cells?
IL-12 (very important in induction of Th1 cell-mediated immunity)
Anti-inflammatory cytokines
IL-10, IL-4
Both are humoral immunity
Pyrogens
IL-1, IL-6, IL-8, TNF-alpha, IFN-gamma
Target of MHC I and II
MHC I - intracellular pathogens (e.g. virus)
MHC II - extracellular pathogens (e.g. bacteria)
