BIOLOGICAL-ACTIVITY OF MONOCLONAL ANTIIDIOTYPIC ANTIBODY REPRESENTINGTHE INTERNAL IMAGE OF THE MAJOR ALLERGENIC COMPONENT OF LOLIUM-PERENNE POLLEN

Upon immunization with an anti-Lol p I (major allergenic component of Lolium perenne pollen) monoclonal antibody, we have previously produce d anti-idiotypic monoclonal antibody (A7H2) displaying some internal i mage properties. The present study was designated to evaluate the capa city of this anti-idiotypic monoclonal antibody to mimic functionally the antigen by triggering histamine release from basophils of patients allergic to Lol p I. Anti-idiotypic monoclonal antibody, as the antig en, could induce histamine release in a dose-response fashion in all o f the atopic patients (6/6). The inhibition of this histamine release by the addition of the idiotype (290A-167) confirmed the specificity o f the reaction. Binding inhibition of human IgE to Lol p I demonstrate d that the anti-idiotypic antibody recognized an idiotope expressed in the antigen-combining site of IgE molecules. Altogether, these data c onfirmed the internal properties of our anti-idiotypic antibody and it can mimic the original antigen in its capacity to trigger histamine r elease.