Abstract
The primary immunization of outbred mice with the antigen Pap-S-DNPL results in the generation of low titers of anti-DNP antibody which in about one-third of the responding animals is as homogeneous as a myeloma protein by the combined criteria of (a) isoelectric focusing in gels and (b) gel electrophoresis of the antibody light chains. The electrophoretically homogeneous antibodies show a marked restriction of isoelectric points near pH 5.0. Such marked selectivity of the antihapten antibodies appears to result from the chemical and structural homogeneity of the Pap-S-DNPL antigen.