Oliver Cromwell talked about recombinant allergens:
The advantages of recombinant proteins are the following: defined/standardized, consistent, avoid contamination/risk of infectious agents, relevant. There is a potential to create modified recombinant allergens for treatment, with less IgE reactivity.
Disadvantages recombinant proteins are the following: each allergen requires a unique process, there are many isoforms, they are expensive in a limited market.
Some allergens (e.g. grass) have several unique relevant allergens, and there may be very different patterns of sensitization. The recombinant allergen rBet v1 works as well as the native birch pollen for immunotherapy, while for grass pollen you need cocktail of several important allergens. "Hypoallergenic" rBet v 1 has the same T cell reactivity. It is safer but as effective as natural birch pollen for immunotherapy.
The recombinant allergens are more available for diagnosis than therapy. Eeach allergen would need to be individually approved by regulatory agencies.
Instead of truly targeted therapy, the current approach to immunotherapy consists of generic "cocktails" of the most common allergens, which sort of defeats the purpose of specific diagnosis.
Disclaimer: The text was edited, modified, and added to by me. I was invited to speak on the topic of social media use by the allergists during the 2011 CSACI meeting.
Related:
Molecular Allergy Component Testing, a video by the manufacturer of ImmunoCAP testing system.