Immune Responses Flashcards Preview

Immunology Manchester > Immune Responses > Flashcards

Flashcards in Immune Responses Deck (9)
Loading flashcards...
1

How do Tregs control inflammation?
What is mechanism?

Produce TGF-β and IL-10
Decrease MHC and antigen presentation and inhibit inflammatory cytokines

2

What is type 1 hypersensitivity?

Allergy
IgE acts in mast cells to cause release of granules
Driven by Th2 cytokines
Second exposure is the allergic reaction. In first one the antibody is made.

3

What are clinical effects of allergic reaction?

Vascular permeability increased
Smooth muscle contraction
Mucus production
Vasodilation

4

What happens in anaphylaxis?

Extreme allergic response
Massive histamine and TNFα release results in drop in blood pressure, swelling of throat and mucus membranes and respiratory collapse

5

What is type 2 hypersensitivity?

Antibody dependent cytotoxicity
E.g. Complement dependent red blood cell degradation

6

What is type 3 hypersensitivity?

Autoantibodies destroy host cells
5 mechanisms:
1) antibody medication activation of complement
2) auto antibody mediated opsonisation
3) autoantibodies and complement mediated neutrophil recruitment
4) auto antibody dependent cell-mediated cytotoxicity
5) antireceptor autoantibodies

7

What are the three pathways form complement activation?

Classical; antigen:antibody complexes
MB-lectin pathway; lectin binds to pathogen surface
Alternative pathway ; antibodies against pathogen surfaces

8

What happens to small immune complexes?

Excess small antigen immune complexes cannot fix complement so are instead taken up into tissues .
This can effect the tissue;
In skin: arthus reaction
In synovial fluid: arthritis
In kidney glomerulus : glomerulonephritis
In epithelium of blood vessels: vasculitis
In joints: SLE

9

What is type 4 hypersensitivity?
What are the three syndromes?

Only one mediated by T cells
1-3 days to occur due to T cell maturation time and need large dose of antigen

Delayed-type
Contact
Gluten-sensitive