Genetic control of the immune response to staphylococcal nuclease. XI. Effects of in vivo administration of anti-idiotypic antibodies.

The effects of prior treatment with heterologous anti-idiotypic antibodies on the response to staphylococcal nuclease (Nase) have been examined. Previous studies have shown that 100% of A/J mice treated with Nase in completes Freund's adjuvant produce anti-Nase antibodies possessing a characteristic idiotype (Id). Mice treated with anti-Id antibodies followed by Nase produced levels of Id equal to or greater than those of control animals treated with Nase alone. The appearance of Id in treated mice preceded the appearance of anti-Nase activity, and animals treated with anti-Id alone produced high levels of Id without detectable anti-Nase activity. Id expression in such animals could be detected using anti-Id reagents produced in several different species suggesting that it represented true idiotope expression rather than unrelated molecules reactive only with the anti-Id reagent used for initial treatment. Isolation of the nonantigen-binding Id-bearing molecules (Id') showed them to be immunoglobulins bearing the same idiotopes as do anti-Nase antibodies. However, quantitative comparisons of Id levels vs. amount of Id or Id'-bearing immunoglobulin suggested that the nonantigen-binding immunoglobulins bore fewer idiotopes per molecule than did anti-Nase antibodies. Evidence was also obtained for the production of some nonantigen-binding Id-bearing molecules during the normal immune response Nase. These findings are therefore consistent with the existence of a network of Id-anti-Id interactions in the immune response to Nase.