An intrastrain cross-reactive idiotype associated with anti-p-azophenylarsonate antibodies of BALB/c mice.

This paper describes an intrastrain cross-reactive idiotype, associated with the anti-Ar antibodies of all BALB/c mice tested. The idiotype is present on 20 to 65% of the anti-Ar antibodies of individual BALB/c mice and is localized to the Fab fragment. Adsorption of anti-Ar antibody from an immune serum completely removes the idiotypic activity. Inheritance of the idiotype is linked to the Igh locus, as shown by results obtained with congenic mice. It is present in strains that are Igh-Ia but not in the allotypically related Igh-Ij strains. The idiotype is also present in certain strains belonging to other allotype linkage groups. Expression of the idiotype is suppressed by the administration of rabbit antiidiotypic antibodies before immunization. The BALB/c idiotype is cross-reactive with an idiotype present in a small proportion of anti-Ar antibodies of A/J mice.