When the Immune System Goes Wrong

Question 1

What is hypersensitivity?

Answer 1

Immune response to harmless molecules which can lead to tissue damage

Question 2

What is the immediate hypersensitivity response due to?

Answer 2

Mast cell degranulation and histamine release and when it happens in the skin there is wheal and flare
Wheal is a raised lesion and flare is the surrounding redness

Question 3

The Th2 response to allergies?

Answer 3

Happens when pollen taken up by APC and presenting as peptides to T-cell receptors on CD4 t-cells
activation of CD4 results in Th2 response so cytokines and B-cells activate
igE produced binds to the surface of mast cells so it can degranulate and bind the pollen to produce a response

Question 4

What is desensitisation?

Answer 4

Where patients are given repeated doses in safe environments to control severe allergy responses

Question 5

Graves disease?

Answer 5

negative feedback by thyroxine prevents excess TSH production but in graves there is no feedback loop