title: Tomato allergy: detection of IgE-binding lipid transfer proteins in tomato derivatives and in fresh tomato peel, pulp, and seeds.
abstract: There is an increasing consumption of tomatoes worldwide: fresh in salads, cooked in household sauces, or industrially processed. Although many tomato allergens have been identified, there is no information in the literature on the allergenic components found in commercial tomato products. The primary aim of the study was to evaluate the allergenic profile of commercial tomato products by skin prick tests (SPTs) and IgE/immunoblotting in tomato-allergic subjects. The secondary end point was the study of the IgE-binding profile of tomato peel, pulp, and seeds. Forty tomato-allergic patients, reporting oral allergy syndrome (OAS) at different grades of severity for fresh and, in some cases, also for cooked tomato, were selected on the basis of positive tomato allergy history or open food challenge (OFC). They were evaluated by SPTs with different experimental tomato extracts. SDS-PAGE/immunoblotting was performed to detect tomato allergens, which were then identified by Edman degradation. Twenty-three patients (57.5%) presented first-grade OAS at the OFC, whereas 17 (42.5%) reported severe symptoms. Ten of these 17 patients (25%) reported allergic reactions to cooked tomatoes; in immunoblotting tests, their sera reacted only to lipid transfer protein (LTP). In commercial products, LTP was the only detectable allergen. In contrast to other LTP-containing fruits, in tomato, an IgE-binding LTP was identified not only in the peel but also in the pulp and seeds. This study demonstrates that, in fresh tomato, different LTP isoforms are present and allergenic. Industrial tomato derivatives still contain LTP, thus presenting a problem for LTP-allergic patients.
authors.affiliation: Clinical Allergy and Immunology Unit, Foundation Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, IRCCS, Dipartimento di Scienze e Tecnologie Alimentari e Microbiologiche (DiSTAM), Università degli Studi di Milano, Milan, Italy. v.pravettoni@policlinico.mi.it
authors.forename: Valerio
authors.initials: V
authors.lastname: Pravettoni
authors.forename: Laura
authors.initials: L
authors.lastname: Primavesi
authors.forename: Laura
authors.initials: L
authors.lastname: Farioli
authors.forename: Oreste V
authors.initials: OV
authors.lastname: Brenna
authors.forename: Carlo
authors.initials: C
authors.lastname: Pompei
authors.forename: Amedeo
authors.initials: A
authors.lastname: Conti
authors.forename: Joseph
authors.initials: J
authors.lastname: Scibilia
authors.forename: Marta
authors.initials: M
authors.lastname: Piantanida
authors.forename: Ambra
authors.initials: A
authors.lastname: Mascheri
authors.forename: Elide A
authors.initials: EA
authors.lastname: Pastorello
mesh_terms: D000328:Adult; D052179:Antigens, Plant / Q000032:analysis* / Q000276:immunology*; D002352:Carrier Proteins / Q000032:analysis* / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D005638:Fruit / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000276:immunology*; D008297:Male; D010936:Plant Extracts / Q000276:immunology; D010940:Plant Proteins / Q000032:analysis* / Q000276:immunology*; D012639:Seeds / Q000737:chemistry / Q000276:immunology; D012882:Skin Tests
chemical_list: D052179:Antigens, Plant; D002352:Carrier Proteins; D010936:Plant Extracts; D010940:Plant Proteins; C511920:lipid transfer proteins, plant; D007073:Immunoglobulin E