The functional biology of peanut allergens and possible links to their allergenicity

Abstract

Peanut is one of the most common food triggers of fatal anaphylaxis worldwide although peanut allergy affects only 1%‐2% of the general population. Peanuts are the source of highly potent allergenic proteins. It is emerging that the allergenicity of certain proteins is linked to their biological function. Peanut is an unusual crop in that it flowers aboveground but produces its seed‐containing pods underground. This so‐called geocarpic fruiting habit exposes pods and seeds during their development to soilborne pathogens and pests. Pest damage can also open routes of entry for opportunistic fungi such as Aspergillus . Although seed proteins have primary functions in nutrient reservoirs, lipid storage bodies, or the cytoskeleton, they have also evolved to act as part of the plant's defense system to enhance fitness and survival of the species. When interacting with pathogens or pests, these proteins modify and damage cells' membranes, interact with immune receptors, and modulate signaling pathways. Moreover, following exposure, the immune system of predisposed individuals reacts to these proteins with the production of specific IgE. This review explores the evolutionary biology of peanut and its seed proteins and highlights possible links between the proteins' biological function and their allergenicity.

Proteomic analysis of oilseed cake: a comparative study of species‐specific proteins and peptides extracted from ten seed species

“…For other species examined within this study, no allergic reactions have been reported, or allergic responses triggered after exposure by the food route are extremely rare. But when developing new products, food technologists must be aware of potential cross‐reactions caused by protein homologues; for instance, peanut allergen homologues have been found in sunflower and pumpkin seeds, and many structural similarities between helianthinin and soy globulin 11S (glycinin) have been observed 13,14 …”

“…However, frequently, illegal adulterations to the composition of food products are economically motivated, 12 and this involves a risk of allergic reactions among consumers. In addition to food fraud, diets based on vegetable proteins may be the reason for an increase in the occurrence of food allergies in society as a result of cross‐reactions between protein homologues 13,14 . Consequently, there is an urgent need for research to determine the exact protein profiles in foods.…”

Recent developments and highlights in food allergy

“…22 New diagnostic component data have highlighted and supported the clinical value of Cor a 9, Cor a 14 for hazelnut allergy, Jug r 1 for walnut allergy, and Ana o 3 for cashew and possibly pistachio allergy [23][24][25] in addition to well-established peanut data. 26,27 A Europe-wide approach to study hazelnut allergy suggested that combinations of component-resolved diagnosis (CRD)-based approaches with clinical history and extract data are superior to CRD alone. 28 Recently, data on the evolution of the molecular IgE repertoire over the first 10 years were published on the Multicenter Allergy Study in Germany 29 and cross-sectional data on a highrisk preschool cohort in North America 30 and in a cross-sectional Austrian cohort 31 provided important data for future study design.…”

Advances and novel developments in molecular allergology

“…Only a minority of the population develops allergic sensitization to certain proteins. The biological function of allergenic proteins, the genetic predisposition, and environmental factors are all involved in the training of the immune system and contribute to this process 116,117 . A recent review by Ozias‐Akins and Breiteneder underscored the link between the defense functions of seed storage proteins and their sensitizing capacity 116 .…”

“…The biological function of allergenic proteins, the genetic predisposition, and environmental factors are all involved in the training of the immune system and contribute to this process 116,117 . A recent review by Ozias‐Akins and Breiteneder underscored the link between the defense functions of seed storage proteins and their sensitizing capacity 116 . Many peanut allergens display anti‐microbial/fungal properties by disrupting pathogen membranes, inhibiting pathogen growth, or they regulate cell mobility.…”