Allergology Clinic, Clinica San Carlo, Paderno Dugnano, Milan, Italy2
Clinical Pathology U.O.C., Buccheri La Ferla F.B.F. Hospital, Palermo, Italy3
Allergology and Immunology SOS, Prato-Azienda USL Toscana Centro, Prato, Italy4
Allergy and Immunology Unit, Istituti Clinici Scientifici Maugeri, IRCCS, Pavia, Italy5
UOC General Medicine Immunology and Allergology - IRCCS Foudation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy6
Clinical and Laboratory Molecular Allergy Unit, Istituto Dermopatico dell'Immacolata, Rome, Italy7
Allergy Diseases Center, "Prof. Giovanni Bonsignore" Institute for Biomedical Research and Innovation, National ResearchCouncil (CNR), Palermo, Italy8
Institute of Translational Pharmacology (IFT), National Research Council (CNR), Palermo, Italy9
Immunology and Allergology Unit, S. Maria degli Angeli Hospital, Pordenone, ItalyHistory
Published online: 16 April 2021
Accepted: 22 March 2021
Received: 31 December 2020
Based on the cross-reactivity between pollen lipid transfer proteins (LTPs) and the peach LTP, Pru p 3, it has been suggested that the pollen might initiate the LTP sensitization process.
To establish whether LTP allergy can be considered as a pollen-food syndrome.
The literature was reviewed and new data of component-resolved diagnosis from Italy obtained by both ISAC immunoassay and ImmunoCAP on large populations of LTP hypersensitive patients were provided and analyzed.
Among Pru p 3 reactors, patients positive for Art v 3 and Pla a 3 largely exceeded those sensitized to the respective major pollen allergens, Art v 1 and Pla a 1/Pla a 2. Pru p 3 reactivity remained stable around 80-90% at all ages, whereas Art v 3 and Ole e 7 recognition was missing in younger patients. Pru p 3 IgE exceeded IgE specific for pollen LTP at all ages. Inhibition studies carried out on LTP reactors showed that commercial extracts of mugwort and plane pollen were unable to inhibit significantly Pru p3 IgE reactivity. In follow-up studies, baseline Pru p 3 IgE levels exceeded Art v 3IgE levels in 84% of those sensitized to both allergens, and all patients positive toonly one LTP allergen at baseline were sensitized to Pru p 3. Further, most of the patients who did not show any LTP reactivity at baseline became exclusive Pru p 3 reactors. On ImmunoCAP singleplex Pru p 3 IgE levels exceeded Art v 3 IgE levels in 89% of cases (p < 0.0001). Most literature data were in keeping with these new observations.
The evidence for LTP syndrome being a pollen-food syndrome is presently very thin. Our data do not rule out the possible sensitization to the protein, via the airways or the skin.
Food allergy; lipid transfer protein; pollen allergy; cross-reactivity; peach allergy.