Use of immunoprecipitates to obtain monospecific immunoglobulins to nuclease 1 of Tradescantia

Progressively more specific immunoglobulins were raised in rabbits against nuclease 1 of Tradescantia paludosa, the final antiserum being monospecific. The original antiserum raised against the purified enzyme preparation gave rise to several immunoprecipitates when tested by crossed Immunoelectrophoresis in agarose gels against the homologous antigen. Part of the immunoprecipitate containing the nuclease, recognized by histochemical staining, was excised from the gel and used to immunize more rabbits. The immunoprecipitate excision cycle was repeated to obtain the final antiserum, which was demonstrated to be monospecific by crossed immunoelectrophoresis with an intermediate gel containing the final antiserum placed between the strip containing antigen, and the reference gel containing the original polyspecific serum. The monospecific immunoglobulin preparation, as well as possessing precipitin activity, was shown to inhibit the DNase activity of the purified nuclease 1 in vitro.