1 Flashcards
What sort of infections would a sickle cell patient be more susceptible to?
Encapsulated bacteria: Some Nasty Killers Have Some Capsule Protection. S. pneumoniae N. meningitidis Klebsiella pneumoniae Haemophilus influenzae Salmonella typhi Cryptococcus neoformans Pseudomonas aeruginosa
Which cytokines stimulate NK cells?
IL-12, IFN-α, and IFN-β
What’s an example of a cytotoxic (type II) hypersensitivity reaction? What mediates this reaction?
Mediated by IgG (B-cells).
Goodpasture’s syndrome, Grave’s, MG, autoimmune hemolytic anemia, Immune thrombocytopenic Purpura (ITP), erythroblastosis fetalis.
What cells mediate type IV (delayed-type) hypersensitivity rxns? Provide some examples.
PPD, contact dermatitis (e.g. poison ivy), MS
Which type of hypersensitivity reaction is immune complex disease? Mediators? Mech?Examples?
Type III hypersensitivity.
IgG - More Ag than Ab, forming complexes, which deposit in capillaries, glomeruli, and joints.
Lupus nephritis, PSGN, Polyarteritis nodosa, Reactive arthritis, serum sickness, farmer’s lung, Arthus reaction.
Th1 cell
functions, cytokines
cell-mediated response
IL-2, IFN-gamma
activate MΦs and Tc
Th2 cell
functions, cytokines
humoral response
IL-4, IL-5
induce Ab production in B-cells (esp. IgE)
Second signal req’d for Th cell activation
B7 (on APC) to CD28
second signal req’d for Tc activation
IL-2 from Th cell
both signals req’d for B-cell activation by Th cell.
First, BCR clustering. Then:
1. IL-4,-5,-6
2. CD-40L to CD-40
+ co-stimulatory CD-28/B7 binding
cytokines released in macrophage-lymphocyte interaction
lymphocyte releases IFN-γ
MΦ releases TNF-α and IL-1
What anti-inflammatory cytokines are released by Treg cells?
IL-10, TGF-β
What are thymocyte-independent antigens?
Ag’s w/o a peptide component, and therefore cannot be presented to Th cells of MHCs. Only stimulate IgM, No immune memory.
What event instigates T-cell anergy?
Binding to antigen via TCR without receiving a co-stimulatory signal.
