Trees within the order Fagales possess particularly potent allergens, e.g. the prototypical Bet v 1, the major white birch (Betula π» verrucosa - now called B. pendula) pollen antigen. Bet v 1 is the main cause of type I allergies observed π» in early spring. Type I, or immunoglobulin E-mediated (IgE-mediated) allergies affect 1 in 5 people in Europe and North America. π» Commonly observed symptoms are hay fever, dermatitis, asthma and, in severe cases, anaphylactic shock. First contact with these allergens results π» in sensitisation; subsequent contact produces a cross-linking reaction of IgE on mast cells and concomitant release of histamine. The inevitable π» symptoms of an allergic reaction ensue.
Categorization [ edit ]
A nomenclature system has been established for antigens (allergens) that cause IgE-mediated π» atopic allergies in humans.[2] This nomenclature system is defined by a designation that is composed of the first three letters π» of the genus; a space; the first letter of the species name; a space and an Arabic number. In the π» event that two species names have identical designations, they are discriminated from one another by adding one or more letters π» (as necessary) to each species designation.
The allergens in this family include allergens with the following designations: Bet v 1, Dau π» c 1, and Pru a 1. Other proteins belonging to this family include the major pollen allergens:
Structure [ edit ]