[Immunogenicity studies in experimental animals immunized with a low-molecular antigen alone and the antigen plus adjuvants].

The present studies were undertaken to clarify the immunogenicity evoked in four species, the guinea pig, rabbit, F344 rat and A/J mouse, immunized with a low-molecular antigen (TNBS) alone, TNBS plus Alum and TNBS plus FCA. Each species was divided into three groups: TNBS alone sc group, TNBS plus Alum ip groups (one and 3 times sensitization) and TNBS plus FCA sc groups (one and 3 times sensitization), and immune responses to TNBS were estimated by the assay systems of humoral immunoreactions (HA.PCA.SANA.Arthus) and cellular immunoreaction (DTH by the intracutaneous method & application method). All of the species showed significantly positive humoral immune responses in the TNBS alone sc group, the TNBS plus Alum ip groups and in the TNBS plus FCA sc groups. Nearly all of the guinea pigs and rabbits displayed positive cellular immune response (DTH by the intracutaneous method), while such immune response was never recognized in the rat groups. These results suggest that TNBS is a useful model compound as a positive control for the antigenicity tests of novel drugs.