Tomato nsLTP as an "In Vivo" Diagnostic Tool: Sensitization in a Mediterranean Population

Tomato allergies have been extensively studied but component-resolved in vivo diagnosis with purified allergens has yet to be performed.

To evaluate the prevalence of sensitization to Sola l 3 in a Mediterranean population, and to compare the resulting sensitization profile with that of individuals sensitized to tomato, peach, and/or purified lipid transfer protein (LTP).

Sola l 3 was purified, characterized, and used to prepare skin prick tests (SPTs). Two groups of patients were selected. Group 1 consisted of patients with at least 1 positive SPT to tomato, peach, or LTP mixture (marker extracts) who were subsequently tested with Sola l 3 (n = 280). Group 2 (prevalence study) consisted of patients who underwent simultaneous SPT with the 3 marker extracts and Sola l 3 (n = 658). Patients from either group who were positive to any of the 4 extracts were studied in detail (study group, n = 1 23). ELISA and immunoblot assays were performed in individuals with a positive SPT to Sola l 3 to detect the presence of specific IgE antibodies to this allergen.

Prevalence of sensitization to Sola l 3 was 3.2% overall and 54.7% in tomato-positive patients. Most tomato-sensitized patients were asymptomatic. Symptoms were more common in Sola l 3-positive individuals. Sensitization to peach and the LTP mixture did not discriminate between Sola l 3-positive and Sola l 3-negative patients.

This study confirms that LTP, not only from peach but also from other fruit and vegetables, including tomato, is an important allergen in the Mediterranean area. Sensitization to Sola l 3 is associated with more symptoms in tomato-sensitized patients.