Allergens from Edible Insects: Cross-reactivity and Effects of Processing

Abstract

Purpose of Review The recent introduction of edible insects in Western countries has raised concerns about their safety in terms of allergenic reactions. The characterization of insect allergens, the sensitization and cross-reactivity mechanisms, and the effects of food processing represent crucial information for risk assessment. Recent Findings Allergic reactions to different insects and cross-reactivity with crustacean and inhalant allergens have been described, with the identification of new IgE-binding proteins besides well-known pan-allergens. Depending on the route of sensitization, different potential allergens seem to be involved. Food processing may affect the solubility and the immunoreactivity of insect allergens, with results depending on species and type of proteins. Chemical/enzymatic hydrolysis, in some cases, abolishes immunoreactivity. Summary More studies based on subjects with a confirmed insect allergy are necessary to identify major and minor allergens and the role of the route of sensitization. The effects of processing need to be further investigated to assess the risk associated with the ingestion of insect-containing food products.

Biochemical and clinical studies of putative allergens to assess what distinguishes them from other non-allergenic proteins in the same family

“…Noteworthy is that the rest of > 6000 members of the MDH protein family are not reported as allergens. Therefore, this highly diverse spectrum of the prevalence of allergens in protein families, from the highly allergenic Bet v 1 family to the sparsely allergenic MDH family, underscores the complexities in drawing conclusions from bioinformatic analysis of protein sequences that are being considered for introduction into the diet (NAS 2016 ; Ribeiro et al 2018 ; FDA 2019 ; Abdelmoteleb et al 2021 ; De Marchi et al 2021 ; Montanari et al 2021 ).…”

“…Search tools, such as FASTA or BLAST, are used to assess the relatedness of a protein of interest with sequences of proteins in an allergen database. These allergen databases provide a valuable bioinformatic resource used by developers of new sources of dietary proteins (Muraro et al 2014 ; FDA 2019 ; De Marchi et al 2021 ; Montanari et al 2021 ) and genetically-modified (GM) crops (EFSA 2006 , 2011 ; Codex 2009 ).…”

Road to The Red Carpet of Edible Crickets through Integration into the Human Food Chain with Biofunctions and Sustainability: A Review

“…The 'Guidance on sustainable cricket farming' highlights the risk of chemical contaminants during the rearing processes. Chemical hazards pertaining to raw and processed crickets include heavy metals (cadmium, arsenic, chromium, lead and tin) [103], allergens (tropomyosin, arginine kinase and the specific allergen in G. bimaculatus, hexamerin B1) [103, 127,128], polybrominated diphenyl ether (PBDE) flame retardants [129], dioxins (polychlorinated dibenzodioxins and dioxin-like polychlorinated biphenyls) [15] and high pesticide residues (carbamate and organophosphate) [130]. Whole crickets, cricket powder and cricket protein hydrolysates contain tropomyosin; thus, individuals with prawn allergy may experience an allergic reaction after consuming crickets [128].…”

Monitoring Yellow Mealworm (Tenebrio molitor) as a Potential Novel Allergenic Food: Effect of Food Processing and Matrix

“…Edible insects are considered a valuable source of nutrients such as polyunsaturated fatty acids, essential amino acids, micronutrients, and proteins, having a nutritional value comparable or superior to those of both chicken and beef [ 2 , 3 ]. Additionally, they present a lower negative environmental impact than conventional animal-derived protein sources, with less greenhouse gas emissions and water pollution and higher feed conversion efficiency [ 4 , 5 ]. Therefore, in the near future, insects are expected to become important nutrient sources for animal and human consumption in western countries [ 5 , 6 ].…”

“…Primary sensitization to edible insect allergens is relatively common via inhalation or skin contact, though their action as primary sensitizers through ingestion is still being evaluated. One major allergenic risk derives from the possible occurrence of cross-reactions with the arthropod pan-allergens, namely, tropomyosin and arginine kinase, which are present in crustaceans and mollusks [ 4 , 12 ]. Ribeiro et al [ 13 ] listed several studies assessing the cross-reactivity between crustaceans and edible insects, all of them being attributed to tropomyosin or arginine kinase, the allergens causing clinically relevant symptoms.…”