Rosette-forming cells and the immunological response after DNCB, DNP-carrier and oxazolone sensitization.

Guinea-pigs have been sensitized with DNCB, DNP-guinea-pig serum and DNP-guinea-pig erythrocytes. Four, six and ten days after sensitization numbers of rosette-forming cells with DNP-erythrocytes were estimated in the draining lymph nodes. It was found that the numbers of DNP-erythrocyte RFC did not correlate with humoral immunity as estimated by haemagglutination assay, but did so with cell-mediated immunity estimated as delayed-type hypersensitivity. On the other hand histological examination of the draining lymph nodes gave no clear confirmation of such a relationship. Experiments on the antigenic specificity of RFC showed that after DNCB sensitization a clear increase in oxazolone-erythrocyte RFC and SRBC RFC can be found. These latter data suggest formation of RFC to be at least partly a non-specific phenomenon.