Non-specific lipid-transfer proteins : Allergen structure and function, cross-reactivity, sensitization, and epidemiology

• Main Authors: Skypala, Isabel, Asero, Riccardo, Barber, Domingo, Cecchi, Lorenzo, Díaz-Perales, Araceli, Hoffmann-Sommergruber, Karin, Pastorello, Elide Anna, Swoboda, Ines, Bartra, Joan, Ebo, Didier, Faber, Margaretha A., Fernández-Rivas, Montserrat, Gomez, Francisca, Konstantinopoulos, Anastasios. P., Luengo Sánchez, Olga, van Ree, Ronald, Scala, Enrico, Till, Stephen J., Universitat Autònoma de Barcelona
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2021
• Subjects: Allergy; Epidemiology; Food; Lipid transfer protein; LTP; Sensitization; North Atlantic
• Online Access: https://ddd.uab.cat/record/241072

Discovered and described 40 years ago, non-specific lipid transfer proteins (nsLTP) are present in many plant species and play an important role protecting plants from stressors such as heat or drought. In the last 20 years, sensitization to nsLTP and consequent reactions to plant foods has become an increasing concern. The aim of this paper is to review the evidence for the structure and function of nsLTP allergens, and cross-reactivity, sensitization, and epidemiology of nsLTP allergy. A Task Force, supported by the European Academy of Allergy & Clinical Immunology (EAACI), reviewed current evidence and provide a signpost for future research. The search terms for this paper were "Non-specific Lipid Transfer Proteins", "LTP syndrome", "Pru p 3", "plant food allergy", "pollen-food syndrome". Most nsLTP allergens have a highly conserved structure stabilised by 4-disulphide bridges. Studies on the peach nsLTP, Pru p 3, demonstrate that nsLTPs are very cross-reactive, with the four major IgE epitopes of Pru p 3 being shared by nsLTP from other botanically related fruits. These nsLTP allergens are to varying degrees resistant to heat and digestion, and sensitization may occur through the oral, inhaled or cutaneous routes. In some populations, Pru p 3 is the primary and sole sensitizing allergen, but many are poly-sensitised both to botanically un-related nsLTP in foods, and non-food sources of nsLTP such as Cannabis sativa, Platanus acerifolia, (plane tree), Ambrosia artemisiifolia (ragweed) and Artemisia vulgaris (mugwort). Initially, nsLTP sensitization appeared to be limited to Mediterranean countries, however more recent studies suggest clinically relevant sensitization occurs in North Atlantic regions and also countries in Northern Europe, with nsLTP sensitisation profiles being broadly similar. These robust allergens have the potential to sensitize and provoke symptoms to a large number of plant foods, including those which are raw, cooked or processed. It is unknown why some sensitized individuals develop ...