Sequential anti-idiotypes define reciprocal idiotopes on the same anti-DNA antibody

Sequential anti-idiotypes have defined a pair of idiotypes with an idiotype-anti-idiotype relationship to each other in the variable region of the monoclonal anti-DNA antibody 16/6. A rabbit immunized with 16/6 made an antibody-1 (anti-Id-16/6R) and an antibody-2 (anti-anti-Id-16/6 or anti-anti-Id 16/6M). The latter bound to M-2, a monoclonal mouse anti-Id-16/6. M-2 was used to immunize a second mouse, which produced M-16. The variable region of M-16 mimics an antigenic surface on Id-16/6 and binds to a peptide contained within the first hypervariable region of the light chain of 16/6. The complementary idiotypes of 16/6 represent a reciprotope, an idiotype/anti-idiotype pair within the variable region of the same immunoglobulin molecule which may have functional importance.