title: Transition from T cell protection to T cell enhancement during tumor growth in an allogeneic host.
abstract: The cell-mediated immune response of mice toward a lethal allogeneic tumor was investigated during tumor development. The activity of spleen cells from the tumor-bearing mice was studied by transferring them together with 3LL tumor cells into normal C3H/eb recipient mice. The activity depended upon the time interval between inoculation of the tumor and transfer. Spleen cells taken relatively early, 1 week after tumor inoculation, mediated protection against tumor growth. In contrast, spleen cells taken 4 weeks after tumor inoculation markedly enhanced tumor growth. The tumor-enhancing cells, like the tumor-protecting cells, appeared to be T lymphocytes. The enhancing activity could be transferred by extra cellular medium prepared by incubating the enhancing T cells. Protecting activity could not be transferred by cell-free medium prepared from the protecting T cells. Both activities were found to exist to a relatively slight degree in populations of spleen cells from normal mice. The transition from T cell protection to T cell enhancement might be a determining factor in the outcome of the host-tumor relationship.
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic; D002474:Cell-Free System; D003470:Culture Media; D005260:Female; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000276:immunology*; D009929:Organ Size; D012513:Sarcoma, Experimental / Q000276:immunology*; D013154:Spleen / Q000033:anatomy & histology / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000033:anatomy & histology; D013997:Time Factors
chemical_list: D003470:Culture Media