Changes

Jump to navigation Jump to search

Type I Hypersensitivity (view source)

Revision as of 11:33, 29 August 2008

477 bytes removed ,  11:33, 29 August 2008
no edit summary
Line 12: Line 12:  
* Ranges from mild cases, such as hayfever, to life-threatening reactions, such as bee-stings.  
 
* Ranges from mild cases, such as hayfever, to life-threatening reactions, such as bee-stings.  
 
* Antigens that induce a type I reaction are known as allergens.
 
* Antigens that induce a type I reaction are known as allergens.
−
* Affects face, eyes, nose and feet
+
* Generally affects face, eyes, nose and feet
 
* IgE has a high affinity to IgE receptors on mast cells and basophils, and so binds these receptors.
 
* IgE has a high affinity to IgE receptors on mast cells and basophils, and so binds these receptors.
−
* The individual mechanisms of cell degranulation may only have a marginal effect, but the combination can be highly effective in removing parasite infection
  −
* Eosinophils can also target IgE bound to helminths.
  −
** May either be attracted to the site of inflammation or produced de novo in response to cytokines.
  −
** Binding triggers their degranulation.
  −
*** Potent biological molecules are released.
  −
**** Eosinophil peroxidase.
  −
**** Eosinophil basic protein.
  −
* This system can be invoked with inappropriate and innocuous antigens.
  −
** E.g. pollen.
  −
** Under these circumstances we get hay fever.
        −
==Common allergens:==
+
==Common allergens which elict a type I hypersensitivity reaction:==
    
* Proteins : Foreign serum
 
* Proteins : Foreign serum
Line 44: Line 34:  
* Allergen exposure causes IgE  production.
 
* Allergen exposure causes IgE  production.
 
* IgE coat mast cells by binding to Fc receptors.
 
* IgE coat mast cells by binding to Fc receptors.
 +
* Mast cells are now sensitised to this particular allergen.
     
Mmadment
469

edits

Retrieved from "https://en.wikivet.net/Special:MobileDiff/32472"

Navigation menu