Demonstration of the clonality and specificity of an auto-antibody response to a suppressed immunoglobulin allotype of the rabbit kappa chain b locus.

A regulatory idiotypic network is proposed to control allotype expression in normal rabbits. We have used suppression of the kappa chain b6 allotype in an attempt to restrict the number of regulatory idiotypes involved in an induced auto anti-allotype response. These auto anti-b6 antibodies were examined by an agarose imprint immuno-fixation IEF technique using iodinated allotype-bearing IgG. All totally b6-suppressed rabbits produced a clonally complex response which was generally spectrotypically unique - thus contradicting previous claims of a dominant common idiotypic pattern. The compensating light chains thus have available as many regulatory V genes as does the kappa 1 light chain. However, the b6/b6 homozygotes breaking b6 suppression produce an auto anti-b6 antibody which does not interact with their "escaping" molecules and which is clonally restricted. We propose a regulatory mechanism limiting the V genes utilised to produce the autoantibody, the latter then allowing only molecules bearing non-interactive allotopes to "escape" suppression.