The quest for ingested peanut protein in human serum

• DOI: 10.1111/all.14109
• Publication Date: 2019-11-12T19:53:39Z
• Authors: Anja Pahlow Mose; Ejvind Mortz; Per Stahl Skov; Charlotte Gotthar...; Esben Eller; Ulrik Sprogøe; Torben Barington; Carsten Bindslev‐...
• Keywords: Arachis; Allergens; Antigens, Plant; 03 medical and health sciences; 0302 clinical medicine; Ara h 6; allergen quantification; Ara h 2; Humans; Peanut Hypersensitivity; allergen absorption kinetics; 2S Albumins, Plant; Plant Proteins

AbstractBackgroundThere is mounting evidence that systemic uptake of food allergens is key to triggering anaphylaxis. However, direct proof for this theory is still lacking. The purpose of this study was to quantify the absorption and to determine the absorption kinetics of immunoreactive peanut protein in relation to the allergic response in human.MethodsQuantitative protein assays including mass spectrometry, dot blots and Western blotting were developed to determine the level of Ara h 2 absorption in human serum. The double monoclonal sandwich ELISA was applied to quantify absorbed Ara h 2 and 6, and the basophil histamine release assay and the human passive cutaneous anaphylaxis test were utilized to study the absorption kinetics of immunologically intact peanut proteins.ResultsThe protein assays worked but were not sensitive enough to trace the minute amounts of absorbed Ara h 2 in human serum. The level of Ara h 6 in serum was found to be up to 0.2 ng/mL, but Ara h 2 could not be detected with the ELISA. Both the in vivo and the in vitro methods were successful in demonstrating that: immunoreactive peanut protein was absorbed shortly after ingestion (≤5 minutes); the peanut protein concentration peaks between 1 and 4 hours; and peanut proteins can circulate for at least 48 hours in the bloodstream.ConclusionIngested peanut protein is absorbed systemically and retains its immunoreactive capacity in human serum. However, the precise quantities and the implication for the elicitation of anaphylaxis remains to be elucidated.