Lack of interspecies barriers in anti–Id stimulated antibody production against Echinococcus granulosus antigens

Polyclonal human anti-hydatid antibodies were affinity purified from a hydatid patient serum and used to produce a rabbit anti-idiotypic serum. These anti-Id antibodies cross-reacted in ELISA with sera from 11 of 12 hydatid patients studied and with 13 infected or immunized mice sera. All mice primed and boosted with anti-Id produced anti-hydatid antibodies in the primary response and exhibited an increase in antibody titre after a booster injection. The same effect was observed with mice primed with antigen and boosted with anti-Id, although these mice exhibited higher antibody titres. A significant idiotype repertoire is shared by anti-hydatid antibodies produced by different individuals of the same or different species, and anti-Id raised against those antibodies behave as surrogate antigens producing a normal primary and secondary response in animals of different species from that used to isolate the Id.