Effect of in vitro gastric and duodenal digestion on the allergenicity of grape lipid transfer protein

University of Amsterdam, Amsterdamo, North Holland, Netherlands
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 09/2006; 118(2):473-80. DOI: 10.1016/j.jaci.2006.04.057
Source: PubMed

ABSTRACT Severe grape allergy has been linked to lipid transfer protein (LTP) sensitization. LTPs are known to be resistant to pepsin digestion, although the effect of gastroduodenal digestion on its allergenicity has not been reported.
We sought to investigate the effect of gastric and gastroduodenal digestion on the allergenic activity of grape LTP.
The proteolytic stability of grape LTP was investigated by using an in vitro model of gastrointestinal digestion. The allergenicity of LTP and its digesta was assessed in vitro by means of IgE immunoblotting, RASTs, and in vivo skin prick tests in the same patients with grape allergy.
Grape LTP was resistant to gastric digestion, and yielded a 6000-d relative molecular mass C-terminally trimmed fragment after duodenal digestion. This fragment retained the in vitro IgE reactivity of the intact protein. Inclusion of phosphatidylcholine during gastric digestion protected the LTP to a limited extent against digestion. Digestion did not affect the in vivo (skin prick test) biologic activity of LTP.
The allergenic activity of grape LTP was highly resistant to in vitro digestion. This property might facilitate sensitization through the gastrointestinal tract and might also potentiate the ability of LTPs to elicit severe allergic reactions in sensitized individuals.
Purified natural allergens will facilitate the development of component-resolved diagnostic approaches, including allergen chips. This study contributes to our understanding of the role digestion plays in symptom elicitation in true food allergy.

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    • "This ability to bind lipid affects the stability of some LTPs and their resistance to hydrolysis (Breiteneder & Mills, 2005; Douliez et al., 2000; Vassilopoulou et al., 2006). The 2S albumin and LTP protein families both include a number of major allergens, including SFA8 from sunflower (Yagami, 2010), Ara h 2 from peanut (Burks et al., 1991) and Ber e 1 from Brazil nut (Pastorello et al., 1998); and LTPs from peach (Pru p 1) (Wijesinha- Bettoni et al., 2010), barley (Wijesinha-Bettoni et al., 2010) apple (Sancho et al., 2005) and grape (Vassilopoulou et al., 2006). "
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    • "Mass Spectrom. 2012, 26, 2905–2912 proportion is consistent with that found for grape LTP (9%), [14] but considerably smaller than that for peach (35%). [15] The breakdown of Pru ar 3 determined in this experiment is more extensive than that obtained for Pru p 3 in a previous study [15] and this might partially explain its lower allergenicity; however, other additional factors that play a role in the physiological digestion of a complex food matrix (instead of a purified protein) might also have an influence. "
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