Peanut rAra h 6 IgE, f447

Ara h 9 is a nonspecific lipid transfer protein (nsLTP) which is a component of peanut allergen. Patients with LTP sensitization may exhibit systemic clinical signs in addition to symptoms associated with oral allergy syndrome.

Allergy component diagnosis is based on the detection of sensitization to allergens at the molecular level using natural highly purified and recombinant allergen molecules, i.e. their individual allergy components.

There are 3 main advantages of this analysis:

• Allergy component diagnostics, gives the ability to differentiate true sensitization from sensitization due to cross-reactivity. This data will help to identify the sources of allergy which can be a single allergy, several closely related allergies or many different allergies.
• Molecular allergodiagnosis eliminates the need for provocation tests and allows to give more concise recommendations regarding the elimination of contact with allergens.
• Molecular allergodiagnostics is necessary in the ASIT selection. For persons with polyvalent (multiple) sensitization it is the most accurate way to determine the most important allergen for which therapy will be carried out.

The allergenic substance includes not one but several protein components that can act as allergens as follows:

Major allergic components are the major allergenic molecules, antibodies to which are found in more than half to 50% of patients in the population reacting to a given source. They are heat stable and more immunogenic. Major are large in size and are found in greater quantities in a given allergen.

Minor allergens are minor, smaller in size and less immunogenic allergenic molecules that are usually contained in smaller amounts within an allergen but are present in many different allergens, sometimes not closely related, providing cross-allergy. That is, allergens with a prevalence of more than 50% are called major allergens and less than 10% are called minor allergens.

Regional variations in IgE sensitization to Ara h 9 have been reported, and therefore it is considered a predictor of clinical peanut allergy in Spanish and Asian populations. LTPs are stable and able to withstand thermal and protease treatments. The analysis showed that patients who were monosensitized to Ara h 9 were more likely to experience symptoms of bronchospasm compared with patients who were not sensitized. Ara h 9 IgE has limited diagnostic accuracy in peanut allergy because of cross-reactivity between LTPs, but it may be useful in diagnosing allergy symptoms because of cross-reactivity with other LTPs found in pollen and fruit.