Restoration of Impaired T Cell Functions in Tumor-bearing Mice by the Administration of Interleukin 1

Abstract

The effect of in vivo administration of recombinant human interleukin 1 (IL-1) on T cell functions in tumor-bearing mice was studied using an in vitro assay system. The in vitro induction of trinitrophenyl (TNP)-specific cytotoxic T cell and proliferative T cell responses from spleen cells was impaired in X5563 plasmacytoma-bearing C3H/He mice. However, the administration of IL-1α or IL-1β to tumor-bearing mice restored T cell functions in a dose-dependent manner. Antigen-presenting activities of spleen cells in tumor-bearing mice for T cell activation were not restored by the administration of IL-1. The activities of cytotoxic T cells and cytostatic T cells specific for X5563 cells were also enhanced by the administration of IL-1. Furthermore, in IL-1-treated mice, NK cell activity of spleen cells detected in terms of the killing of Yac-1 cells was also restored. In accordance with these results, the growth of X5563 cells was significantly inhibited and the lymphocytes from IL-1-treated mice specifically inhibited the growth of tumor cells. These results suggest that the in vivo administration of IL-1 restored the impaired T cell and NK cell functions in tumor-bearing mice and activated protective immunity against tumor cells. Thus, recombinant IL-1 can be applied for tumor immunotherapy.