In vitro gastrointestinal digestion of the major peach allergen Pru p 3, a lipid transfer protein: Molecular characterization of the products and assessment of their IgE binding abilities

Abstract

A simulated gastrointestinal digestion has been carried out on purified peach lipid transfer protein, one of the main allergens among the population of the Mediterranean area and the major allergen of peach allergic patients. The percentage of intact protein, after extensive digestion, measured by comparison with a non-digestible peptide analogue used as internal standard, was found to be about one-third of the original protein content. The peptides formed in digested fraction were characterized by means of LC/MS. The products of the digestion essentially derived from trypsin action, whereas the protein appeared to be resistant to pepsin and chymotrypsin. The identified peptides could be classified as low molecular weight and high molecular weight peptides. The latter consisted of the full protein, with the disulfide bridges still intact, deprived of the smaller peptides. The different digestion products, including the high and low molecular weight peptides, were purified by LC and assessed, together with the intact protein, by dot-blot analysis with sera of allergic patients, allowing to estimate their potential allergenicity. The intact protein and the high molecular weight peptides were found to be recognized by patients' sera, whereas the small peptides were found to be not reactive.

Molecular characterization of Api g 2, a novel allergenic member of the lipid‐transfer protein 1 family from celery stalks

“…In fact, sensitization to Pru p 3 has been shown to be associated with an increased risk of both, prevalence and severity of food allergies [34]. We found that Api g 2 was highly resistant to simulated gastrointestinal digestion and although the primary sequence contains 19 potential pepsin cleavage sites it displayed an enormous stability comparable to that of Pru p 3 [35,36]. Even upon prolonged proteolysis (48 h of pepsin and 24 h of trypsin/chymotrypsin treatment) intact Api g 2 could be detected.…”

Cannabis sativaallergy: looking through the fog

“…Furthermore, these reactions are frequently more severe than the classic oral allergy syndrome (OAS) expected in food allergy related to sensitization to Bet v 1, the major allergen from birch pollen (43). This could be explained by the fact that ns-LTPs, unlike Bet v 1 homologues, resist to gastroduodenal proteolysis (44,45) and thermal processing (46)(47)(48). However, it should also be kept in mind that in addition to plant-food allergies, sensitization to Can s 3 might also explain cross-reactions to ns-LTP present in various sources such as Hevea latex (49-51), alcoholic beverages such as beer and wine (52,53) and finally also tobacco (Nicotinia tabaccum) (9, 38, 54).…”

New Food Allergies in a European Non-Mediterranean Region: Is <b><i>Cannabis sativa</i></b> to Blame?

“…ns-LTP are highly stable structures that resist thermal processing [45,46,47] and gastroduodenal proteolysis [48,49]. Thus, both sensitization and triggering of reactions towards C. sativa might result from various routes of exposure such as inhalation, transdermal and also ingestion (e.g.…”