Cupressus arizonica Pollen: A New Pollen Involved in the Lipid Transfer Protein Syndrome?

Background: Lipid transfer proteins (LTP) are responsible for systemic manifestations in food allergy. Their relationship with pollinosis is not clear. In our area, many patients allergic to multiple LTP-containing foods present pollinosis due to Cupressus arizonica. Methods: We selected 6 patients with cypress pollinosis and food allergy to peach. Skin prick tests (SPT) were performed for pollens (grass, cypress, wall pellitory, plane tree, and olive tree) and plant foods (hazelnut, kiwifruit, peach peel, maize, wheat, peanut, lettuce, apple, mustard, and melon). In vitro assays included specific immunoglobulin (Ig) E to C arizonica and peach LTP (Pru p 3), enzyme allergosorbent test (EAST) inhibition, immunoblotting, immunoblotting-inhibition, and immunocytochemical techniques for the detection of Pru p 3 like LIP in cypress pollen grains. Results: SPT were positive for C arizonica, peach, lettuce, mustard, and hazelnut in all patients. Specific IgE to C arizonica and Pru p 3 was positive in all but 1 patient, whose Pru p 3 IgE was negative. Immunoblotting under nonreducing conditions with C arizonica extract and patients' sera showed a band at 14-15 kDa that was inhibited by Pru p3. Pru p3 partially inhibited the Carizonica pollen extract in EAST-inhibition. Pru p 3 like LIP was localized in the cytoplasm and walls of Carizonica pollen grains. Conclusion: A 15-kDa allergen in Carizonica pollen was found in a group of patients presenting peach allergy and respiratory symptoms to cypress. In vitro tests and immunocytochemical techniques indicate that this protein is an LTP.