Epitope analysis of HLA-DR-restricted helper T-cell responses to Der p II, a major allergen molecule of Dermatophagoides pteronyssinus
T-cell of ， a major allergen of ， were analyzed by using T-cell clones. We tested 38 cloned T cells from two Japanese patients with ， and identified at least two (K33-T47 and I58-C73) as helper T-cell . The former was shown to be restricted by *1502， and the latter by *0405， both of which are typical Japanese HLA-DR alleles， suggesting that those T-cell might be important for the onset of in the Japanese population. We prepared 15 analog of the *1502-restricted 15-. Of those 15 residues， five (F35， ， A39， F41， and E42) were critical for the activity， and three residues (F35， A39， and E42) seemed to be included in anchor motifs for *1502. The was also recognized by *1502-positive healthy donors; however， only allergic T cells showed Th2 functions. Antigen-presenting cells of nonallergic donors were able to activate allergic T cells to express Th2 function. This seemed to suggest that antigen recognition of T cells， as well as additional unknown factors which promote Th2， rather than ， responses， might be important for the onset of .