| Abstract: | In an effort to generate heterologous anti-idiotype (Ab2) molecules to a suspected IdX on rabbit anti-a1 antibody (Ab1), goats were immunized with either rabbit or guinea pig Ab1. The goat Ab2 preparations reacted with each of 13 rabbit Ab1, as well as two goat Ab1 samples in serologic assays. From 8 to 50% of the molecules in purified rabbit Ab1 preparations reacted with each goat Ab2. Electron microscopy of immune complexes composed of rabbit Fab anti-a1 and goat Ab2 reveals that the Fab anti-a1 binds to the side of the variable region of most goat Ab2 molecules, rather than at the tip (i.e. in the CDR) as expected. This configuration indicates that the goat Ab2 actually represents a population of induced or enhanced Ig molecules expressing a1-like allotypic or isotypic determinants, rather than an anti-IdX Ab or a paratope-associated internal image of a1. |
