Peanut allergy
A product for oral immunotherapy (OIT) to peanut has been recently
licensed by FDA and EMA and will soon become widely
available109,110.
Other products and routes of administration have been
explored111.
Peanut allergic reactions can be triggered by storage proteins, such as
Ara h 1,2,3,6112,
which have been associated to life-threatening symptoms, as well as by
cross-reactive allergens, such as Ara h
5113, a profilin
associated to grass pollen allergy, Ara h 8, belonging to PR10 family
and associated to birch pollinosis and Ara h 9, a nsLTP, associated to
the LTP syndrome discussed earlier(Table 1). Symptoms elicited by Ara h
5 and Ara h 8 are usually mild and limited to the oral cavity, the
oropharynx, known as oral allergy syndrome. Ara h 2 sIgE levels are
associated to both severity and threshold of allergic reactions during
oral provocation challenges, thus being a good biomarker for severity.114,115.
In fact, Ara h 2 is the dominant 2S globulin
allergen116. As
storage proteins can trigger systemic food allergic reactions and
anaphylaxis, peanut allergy with confirmed sensitization to seed storage
proteins like Ara h 1,2,6 can constitute an indication for POIT to
peanut.
A summary of the decision process to select POIT is shown in Figure 8.