Characterization of the major allergen of plum as a lipid transfer protein

Background: Allergy to Prunoideae fruit (plum, peach, cherry and apricot) i s one of the most frequent food allergies in southern Europe. All these fru its cross-react in vivo and in vitro, as they share their major allergen, a 9 kD lipid transfer protein (LTP). Objective: The aim of the study was the identification and molecular characterization of the major allergen of plu m. Methods: The IgE pattern of reactivity to plums was investigated by SDS- PAGE and immunoblotting with the sera of 23 patients. The identified major allergen was purified by HPLC, using a cationic-exchange column followed by gel-filtration. Further characterization was achieved by periodic-Schiff s tain, isoelectrofocusing and N-terminal amino acid sequencing. Results and conclusions: The major allergen of plum is a 9 kD lipid transfer protein, n ot glycosylated and with a basic character (pI > 9), highly homologous to t he major allergen of peach. (C) 2001 Elsevier Science B.V. All rights reser ved.