Analysis of human IgE epitope of Der f 2 with anti-Der f 2 mouse monoclonal antibodies

Der f 2 is one of the major mite allergens recognized by human IgE antibodi es of allergic patients. Using five anti-Der f 2 mouse monoclonal antibodie s, human IgE epitopes of Der f 2 were analyzed. Among them, two monoclonal antibodies 15E11 and 13A4 inhibited the binding between Der f 2 and human I gE antibodies. To determine major IgE epitopes of Der f 2, epitopes for the monoclonal Ige antibodies were analyzed using 43 single site Der f 2 mutan ts constructed by site-directed mutagenesis. Binding ability of 13A4 and 15 E11 was decreased by the amino acid replacement around the C-terminus, and around 73rd, respectively. These results suggest that the C-terminal portio n and the central portion around 73rd of Der f 2 were recognized by human I gE antibodies as major epitopes. The location of the putative IgE epitopes on 3-D structure of Der f 2 is also discussed. (C) 1999 Elsevier Science Lt d. All rights reserved.