ABSTRACT
The variable regions of immunoglobulin molecules contain antigenic determinants capable of evoking an antibody response. The availability of Rheumatoid Factor (RF)-associated anti-idiotypic reagents provides a means for the comparison of RF produced under various circumstances. Polyclonal anti-idiotypic reagents contain antibodies to a variety of antigenic determinants, including light-and heavy-chain idiotopes, as well as combinatorial determinants contributed to by both heavy- and light-chain regions. Anti-idiotypic reagents specific for the antigen-binding site or paratope of an antibody molecule would be expected to block antigen binding. Experience with monoclonal antibodies directed against RF-associated cross-reactive idiotypes has indicated that some monoclonal anti-idiotypic reagents are not useful for probing the genetic origin of the autoantibodies. Among the anti-idiotypic reagents produced to date, those that have proven most useful for probing the structural diversity of RF have been those that recognize epitopes that appear to be encoded by germline genes.
