Allergy and Asthma Flashcards
What do Treg cell release to maintain the balance between TH1 and TH2?
They release IL-10 and TGF-B
In allergies which T cell is in excess?
More TH2 than TH1
What interleukin causes T cell to differentiate to TH2 cells
IL-4
What is the function of histamine release from mast cells? What symptom can it cause?
Vasodilation
Vascular leak
Angioedema
What is the function of lipid mediators release from mast cells? What symptom can it cause?
Broncho constriction - wheezing
Intestinal hypermotility - diarrhoea and vomiting
What is the function of cytokines (TNF) released from mast cells?
Inflammation
Vessels leakier
What is the cause of the release of enzymes (endogenous triptase) from mast cells?
Chronic tissue damage
When does second phase of allergy occur?
Take up to 6 hours
Which interleukin released from TH2 cells cause eosinophil activation?
IL-5
Which interleukin released from TH2 cells causes smooth muscle cell activation and hyper-reactivity for contraction and release of chemokines and pro-inflammatory cytokines?
IL-13
Activation of eosinophils causes what?
Bronchial hyperactivity
In asthma you have an increase of eosinophils where?
blood
lungs
What is chronic allergic reaction?
Persistent inflammation due to prolonged or repetitive exposure antigens
Leads to substantial changes in extracellular matrix and alters number, phenotype and function of structural cells in affected tissues e.g. scaring
Which cell is in chronic allergic lungs?
Fibroblasts
What are the airways like in chronic asthma?
Vasodilation Mucus hypersecretion which can partially occlude the bronchial lumen Collagen deposition Hypertrophy of smooth muscle Lots of oedema Really thickened basement membrane Desquamation
