Effect of food matrix and processing on release of almond protein during simulated digestion

Abstract The aims of the present work were to assess digestibility of almond protein in the upper gastrointestinal tract, evaluate the effects of food matrix on protein release and assess the persistence of immunoreactive polypeptides generated during simulated digestion. Prunin, the most abundant protein in almond flour, was sensitive to pepsin, with complete digestion after 20 min in the gastric phase. Addition of the surfactant phosphatidylcholine did not affect the rate and kinetic of digestion, as observed by SDS-PAGE analysis and HPLC, in the stomach and the small intestine of either natural or blanched almond flour. However, incorporation of almond flour into a food matrix, such as chocolate mousse and Victorian sponge cake, decreased the rate of almond protein degradation by pepsin and immunoreactivity of almond polypeptides detected by dot blots and sandwich ELISA retained better. Most of the almond protein identified by in-gel tryptic digestion and MALDI-TOF analysis corresponded to prunin, with pI values of 5–7. Further human sera studies are warranted to investigate the relationship between food matrix and almond allergy

Advances in allergen-microarray technology for diagnosis and monitoring of allergy: The MeDALL allergen-chip

Allergy diagnosis based on purified allergen molecules provides detailed information regarding the individual sensitization profile of allergic patients, allows monitoring of the development of allergic disease and of the effect of therapies on the immune response to individual allergen molecules. Allergen microarrays contain a large variety of allergen molecules and thus allow the simultaneous detection of allergic patients' antibody reactivity profiles towards each of the allergen molecules with only minute amounts of serum. In this article we summarize recent progress in the field of allergen microarray technology and introduce the MeDALL allergen-chip which has been developed for the specific and sensitive monitoring of IgE and IgG reactivity profiles towards more than 170 allergen molecules in sera collected in European birth cohorts. MeDALL is a European research program in which allergen microarray technology is used for the monitoring of the development of allergic disease in childhood, to draw a geographic map of the recognition of clinically relevant allergens in different populations and to establish reactivity profiles which are associated with and predict certain disease manifestations. We describe technical advances of the MeDALL allergen-chip regarding specificity, sensitivity and its ability to deliver test results which are close to in vivo reactivity. In addition, the usefulness and numerous advantages of allergen microarrays for allergy research, refined allergy diagnosis, monitoring of disease, of the effects of therapies, for improving the prescription of specific immunotherapy and for prevention are discussed.This work was supported by the European Commission’s Seventh Framework Programme under grant agreement No. 261357 and in part by project F4605 of the Austrian Science Fund (FWF) and the Christian Doppler Research Association, Austri