Predictive model for the sensitising capacity of novel nutritional proteins.

Sustainability considerations require the replacement of animal proteins by
plant- or microbe-based alternatives, and stimulation of the valorisation of
waste streams from existing processes. There is a fast-growing demand for the
production of these (vegetable) proteins that, before they can be used
commercially, must be tested for safety before consumption. One of the most
important safety aspects is screening new products for their potential to cause
an allergic reaction. In order to be able to predict whether a (novel) food can
cause an allergic reaction, the specific proteins that make up the food must
first be identified. An allergic reaction only occurs if the person is
sensitized. The person then makes specific IgE antibodies against the allergen.
There are no suitable animal models available to predict an allergic reaction
in humans.

The assays to be developed will be based on an already existing analysis of in
vitro assays described in the *adverse outcome pathways* (AOP) developed for
food allergy by ImpARAS; the European Allergy Expert Consortium.

The aim of this research project is to develop and test new in vitro assays
that can predict an allergic reaction in vitro. The blood of patients with a
known food allergy is used.

Development of new in vitro assays with blood from well-characterized allergic
donors.

Observational study with interventions.

During visits 1, 2 and 3, a physical examination with blood pressure
measurement and listening to the heart and lungs will take place.
During visit 1, a questionnaire about allergic complaints and a diet-specific
questionnaire are administered. A Skin Prick Test (SPT) is performed with a
history of suspected food allergen (peanut (n=7), or cow's milk (n=7), or
chicken egg (n=7). Subject is only tested with one of the three food allergens
A red itchy bump may develop 15 minutes after the SPT, which will disappear on
its own. 1 tube of blood will be taken by venipuncture. A bruise may develop
after the blood draw, which will disappear on its own. Visit 1 will take 1
hour. take.
During visits 2 and 3, a physical examination will take place with blood
pressure measurement and listening to the heart and lungs. A double blind
placebo controlled food challenge takes place (1 half day challenge with verum
material, 1 other half day challenge with placebo material). Choice of which
allergen (peanut, or cow's milk, or chicken egg) is made on the basis of the
history and the result of the SPT. Participant is only challenged with one of
the three food allergens. Blood is taken through an infusion line that is
standard inserted during food challenges. An allergic reaction may develop
after the DBPCFC, which will disappear after taking an antihistamine. The risks
are limited by starting with a minimal amount of the allergen and gradually
increasing the dose at 30 minute intervals. Complaints are monitored via a
PRACTALL score list. There is always a doctor and a nurse on the ward. A bruise
may develop after insertion of the IV line, which will disappear on its own.
Visits 2 and 3 will take 4 hours each.
For subjects who have undergone a positive DBPCFC with the suspected food
allergen from the anamnesis and SPT, 100 ml of blood is collected during visit
4 by means of a venipuncture. A bruise may develop after the blood draw, which
will disappear on its own. Visit 4 will take 0.5 hours.