Delayed type hypersensitivity in mice immunized with inactivated rabies virus.

Evidence of the DTH reaction is in agreement with in vitro observation done with the lymphoblast transformation test in rabbits (5,8) or with the cytotoxicity test in mice (7). The footpad test (FPT) fulfilled all criteria of DTH. A maximum swelling at the injection site was observed 24 h after challenge. FPT could not be transferred by immune serum. But both local and systemic transfer of dissociated spleen cells or lymph node cells sensitized recipient mice to the FPT. A lymphoproliferative response in the draining lymph node was observed after injection of RV, coinciding with the appearance of circulating cells mediating DTH and this response is not dependent upon a B-cell regulatoring mechanism (3). Evaluation of vaccines in vivo by specific DTH reaction is of interest for testing the cell-mediated immunity of these vaccines.