Peach fuzz contains large amounts of lipid transfer protein: is this the cause of the high prevalence of sensitization to LTP in Mediterranean countries?

Background: Allergy to lipid transfer protein (LTP) is quite common in the Mediterranean countries but virtually absent in Northern Europe. The reasons for this latitude-dependent distribution are unclear. One hypothesis is that peach, the primary sensitizer to LTP, may lose in part its allergenicity as a consequence of treatments (handling, brushing, washing, and packaging) preceding marketing in Northern European. Peach surface fuzz might represent a potential vehicle of LTP. Objective: To detect LTP in peach fuzz, and compare IgE reactivity to peach fuzz and peel of sera from LTP-allergic patients. Methods: IgE reactivity to peach peel and peach fuzz extract was measured by ELISA using sera from 2 LTP-allergic patients. Purified peach LTP was used in inhibition studies. Results: Both sera strongly reacted both to peach peel and fuzz but reactivity to fuzz was stronger than to peel. Pre-absorption of one serum with peach LTP caused an 87% reduction of IgE reactivity to peach fuzz extract. Conclusion: Peach fuzz contains large amounts of LTP and might be a potential vehicle of this allergen causing sensitization in genetically predisposed subjects. Fuzz loss during pre-marketing handling of peaches might be at the basis of the geographic differences that characterize allergy to LTP.