Allergies and IgA

[John King]

I am wondering if IgA can neutralize allergens by binding to them and 
preventing their absorbtion into the body proper or at least 
preventing them from binding sites that would lead to an allergic 
reaction.  If they do then it seems logical to fight allergies by 
somehow getting the body to produce specific IgAs in order to 
neutralize the allergen.  It seems like the present approach is to 
either lower the bodies response to allergens (antihistamines, allergy 
shots etc.) and to produce IgGs to interact with the allergen in the 
blood.  It would be better in my opinion to prevent the allergen from 
even entering the body proper in significant amounts.  IgA can 
neutralize viruses - so why not allergens.