Identification and Characterization of the Allergens in the Tomato Fruit by Immunoblotting

Abstract

Background: Although the tomato fruit (Lycopersicon esculentum) has been widely investigated for breeding purposes, there have been few studies on tomato allergenicity. We attempted to identify the tomato fruit allergens and to compare the concentrations of IgE-binding proteins among the different growth stages with sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Methods: An immunoblot experiment on tomato fruit extracts was performed using sera from 11 patients with oral allergy syndrome (OAS) to tomatoes. Bands reacting with IgE from more than half of the OAS patients’ sera were excised and subjected to determination of N-terminal amino acid sequences using the automated Edman degradation method. Moreover, we compared the concentrations of these proteins at each growth stage of the tomato fruit with SDS-PAGE and immunoblotting. Results: Four proteins binding with IgE from more than half of the OAS patients’ sera were determined to be polygalacturonase 2A (PG2A), β-fructofuranosidase, superoxide dismutase (SOD) and pectinesterase (PE). The concentrations of PG2A, β-fructofuranosidase and PE were highest in the red ripening stage with both SDS-PAGE and immunoblotting. Conclusion: The concentrations of 3 of 4 tomato allergens increased during ripening.

Skin prick test analysis reveals cross-sensitization to tomato profilin and grass pollen in nasobronchialallergic patients with history of tomato food allergy

“…Understanding the spectrum of cross-reactive pollen-food allergies in different populations is required for the proper diagnosis and treatment of such allergic disorders. The association between grass-pollen sensitization and allergy to tomato fruit is known from studies in Europe and Japan (24)(25)(26)28,30); however, there are no reports of such studies in the Indian population. The present study describes a preliminary investigation based on case history and SPT in a study group of 246 allergic rhinitis / asthma patients in Mysuru city, India, aimed at understanding the importance of tomato profilin as a cross-reactive allergen.…”

“…Possibly connected with the sequence diversity, ubiquity, and abundance of profilins in eukaryotes is the fact that plant profilins are important cross-reactive allergens, and are identified as pan-allergens (23). The prevalence of tomato (Solanum lycopersicum L.) allergy was estimated to range from 1.5% to 16% among food-allergic populations (24)(25)(26)(27), and up to 39.2% among grass pollen-allergic patients (28). Profilin from tomato fruit (14 kDa; Sola l 1) has been identified as a food allergen, and has been cloned and characterized (29,30).…”

Molecular Properties of Plant Food Allergens: A Current Classification into Protein Families

“…The glycoprotein Lyc e 2, a fructofuranosidase from tomato, belongs to the glycoside hydrolase family 32 and represents a major allergen of tomato recognized by more than 50% of tomatoallergic individuals. However, one third of the sera from tomato-allergic patients show glycan specific antibodies leading to the speculation that the glycans of Lyc e 2 might contribute to its IgE binding properties [58]. The protein is highly concentrated in the red ripening stage of the fruit.…”

Reduction of Allergenic Proteins by the Effect of theripening inhibitor(rin) Mutant Gene in an F1Hybrid of therinMutant Tomato

“…Of these, -fructofuranosidase and PG-2A had previously been identified as tomato allergenic proteins. 10) On the microarray spots of -fructofuranosidase (clone ID, cLEC6K14) and PG-2A (cLEG12J1), the signal intensities of the rin hybrid fruit were 8.3% and 33% of the wild-type fruit.…”

“…9) To date, the following possible tomato fruit allergens have been identified through an immunoblotting analysis with the patients' sera: PG-2A, -fructofuranosidase, superoxide dismutase, pectinesterase, suberization-associated anionic peroxidase, and profilin. [10][11][12] The allergenicity of a ripe tomato is reportedly higher than that of an unripe tomato. 13) Ripening of tomato fruit involves various biochemical and physiological changes such as increased ethylene production, fruit colour development, softening, seed maturation, flavour, texture, and aroma.…”