Co-sensitization between legumes is frequently seen, but variable and not always clinically relevant

Area of Science:

• Food allergy research
• Immunology
• Nutritional science

Background:

• Peanut and soybean allergies are prevalent, with increasing consumption of other legumes.
• This rise in legume consumption may increase sensitization and allergy risks, especially for those with existing peanut or soybean allergies, due to cross-reactivity.
• Understanding cross-reactivity among legumes is crucial for managing food allergies.

Purpose of the Study:

• To investigate the frequency of co-sensitization and co-allergy among various legumes.
• To identify the role of different legume protein families in cross-reactivity.
• To assess the clinical relevance of legume co-sensitization.

Main Methods:

• Inclusion of six patient groups allergic to specific legumes: peanut, soybean, lupine, green pea, lentil, and bean.
• Measurement of IgE binding to total legume extracts and protein fractions (7S/11S globulin, 2S albumin, albumin).
• Analysis of IgE binding to 16 individual proteins from 10 different legumes using line blot assay.

Main Results:

• Co-sensitization rates among legumes ranged widely from 36.7% to 100%.
• Mono-sensitization was rare, observed only in soybean, peanut, and green pea allergies.
• A high frequency of co-sensitization was linked to 7S/11S globulin fractions across legumes. Co-allergy was uncommon in peanut/soybean-allergic patients but frequent in pea, lupine, lentil, and bean-allergic patients towards peanut or soybean.

Conclusions:

• Legume co-sensitization is common but often not clinically significant.
• Clinically relevant co-allergy to other legumes is infrequent in peanut and soybean-allergic individuals.
• 7S and 11S globulins are the likely drivers of legume co-sensitization.