ABSTRACT
In contrast, the variable region genes used by the anti-IIi light chains do not demonstrate such restriction. Although the anti-I cold agglutinin light chains appear to derive from the VKIII gene family, the anti-i cold agglutinins use light chains from a number of different VK families, including VKIII (54). To ask whether the anti-IIi light chains that use VKIII might exhibit similar idiotypic cross-reactivity as observed for the heavy chains, a panel of eight VKIII light chain-dependent monoclonal anti-idiotypic antibodies were raised against an anti-1 autoantibody expressing V~ and VKIII genes (57). Significant idiotypic heterogeneity was observed among VKIII-expressing cold agglutinin light chains. In addition, the idiotypic heterogeneity could be ascribed to the use of at least three different VKIII gene segments, as well as to somatic diversification of the germline-encoded genes.
