ENGL 100 Lecture Notes - T Helper Cell, Vasoactivity, Allergen
Document Summary
Allergy hypersensitivity reaction of the immune system (type i, immediate. Involves release of vasoactive mediators such as histamine from mast cells/basophils: rapid effect on smooth muscle & blood vessels. Inflammation follows and can lead to a late phase response in addition. Inflammatory process with t helper (th)-cell responses of the th2 phenotype crucial for the initiation and maintenance of this inflammation. Cytokines secreted by the helper cells have been shown to be important mediators of allergic inflammation. Allergy epidemic 40% of the canadian population suffers from one or more of these conditions. Epidemiology asthma and allergy are associated with a westernized life-style, prevalence higher in developed countries. Rapid increase in the prevalence of asthma in children who have migrated from developing countries to developed countries. Potential underpinnings of the epidemic hygiene hypothesis, dietary hypothesis. Early childhood infections inhibit the tendency to develop allergic disease. Toxins in the environment promote the development of atopic disease.