Could IL-33/ST2 pathway play a role in Pru p3-sensitized peach allergic patients?

Background: It has been demonstrated that Interleukin-33 (IL-33)/ST2 axis is involved in the development of allergic diseases but, their contribution in food allergy is still unknown. In this study, we've measured and compared the serum levels of IL-33 and its soluble receptor (s-ST2) in Pru p 3-sensitized peach allergic patients (Pru p 3-SPAP), non-Pru p 3-sensitized peach allergic patients (non-Pru p 3-SPAP) and normal controls. Methods: sIgE anti-rPru p 1, anti-rPru p 3, anti-rPru p 4, IL-33 and s-ST2 receptor were assessed in the sera of 53 control patients, 68 non-Pru p 3-SPAP and 47 SPAP. Within this group, the presence of rhinitis and/or asthma were evaluated. Using the basophil activation test assay (BAT), we assessed basophil activation before and after the addition of s-ST2 to the sera of Pru p 3-SPAP. Results: All Pru p 3-SPAP were only positive to sIgE to Pru p 3. All non-Pru p 3- SPAP and control patients were negative to sIgE to all peach allergens. The highest levels of IL-33 were found in Pru p 3- SPAP compared with non-Pru p 3-SPAP and normal controls. A significant difference between non-Pru p 3-SPAP with rhinitis/asthma and Pru p 3-SPAP without rhinitis/asthma was found. Significantly lower s-ST2 levels were found in Pru p 3- SPAP compared with non-Pru p 3-SPAP. BAT analysis showed a significant decrease in basophil activation after the addition of the s-ST2 to the sera of Pru p 3-SPAP. Conclusions: An imbalance in the IL-33/ ST2 pathway has been found in Pru p 3- SPAP. This data open up new therapeutic approaches for food allergy.