Monoclonal anti-alpha (1----3) dextran antibodies of Igha BALB/c and Ighb C.B20 mice display striking similarities.

Allotype Ighb congenic C.B20 mice when immunized with dextran B1355S are unable to produce anti-alpha (1----3) dextran antibodies that express the VH-associated cross-reactive IdX idiotype. This intrastrain-specific idiotype is normally associated only with the anti-dextran response of Igha mice of which BALB/c is a prototype strain. In this study we have obtained monoclonal hybridoma antibodies specific for the alpha (1----3) glucosidic linkage of dextran from C.B20 mice that were presensitized with rabbit anti-IdX antibodies. These antibodies display the light chain isotype distribution, the H chain amino terminal sequence, share VH-associated IdX idiotypic determinants, and finally the similar fine specificity for dextrans observed for anti-alpha (1----3) dextran antibodies of BALB/c mice.