Cutting edge: Identification of novel T cell epitopes in Lol p5a by computational prediction

Although atopic allergy affects less than or equal to 20% of the total popu lation, the relationship between the protein structure and immunogenic acti vity of the allergens is still largely unknown, We observed that group 5 gr ass allergens are characterized by repeated structural motifs, Using a new algorithm, TEPITOPE, we predicted promiscuous HLA-DR ligands within the rep eated motifs of the Lol p5a allergen from rye grass. In vitro binding studi es confirmed the promiscuous binding characteristics of these peptides. Mor eover, most of the predicted ligands were novel T cell epitopes that were a ble to stimulate T cells from atopic patients. We generated a panel of Lol p5a-specific T cell clones, the majority of which recognized the peptides i n a crossreactive fashion. The computational prediction of DR ligands might thus allow the design of T cell epitopes with potential useful application in novel immunotherapy strategies.