title: Development of suppressor T-cells in Mycobacterium habana-infected mice.
abstract: Mice were infected intravenously with increasing numbers of Mycobacterium habana (simiae serotype II), and the levels of delayed-type hypersensitivity to purified protein derivative and M. habana cytoplasmic protein antigen were determined after 14, 30, and 90 days. A footpad delayed-type hypersensitivity response was seen in 14-day-infected mice and was followed by a persisting anergy. T-cell-enriched suspensions collected 30 and 90 days into the infection (anergic donors) showed depressed transformation indexes after phytohemagglutinin and M. habana cytoplasmic protein antigen treatment in vitro. The corresponding B-cell mitogen (lipopolysaccharide) responses were not affected. Mixing experiments with T-cell-enriched suspensions from day-90 M. habana-infected donors adoptively suppressed lymphocyte transformation by normal and day-14 spleen cells. This effect could be ablated by anti-theta serum and complement treatment of the day-90 cells, indicating that the lack of in vitro responsiveness to cytoplasmic protein antigen was mediated by a population of suppressor T-cells present in the heavily infected spleens. There was no evidence that similar cells were present in the spleens of the 14-day-infected animals. Suppressor T-cells could be induced in vitro by exposure of day-14 spleen cells to concanavalin A or M. habana cytoplasmic protein antigen before they were mixed with normal or day-14 indicator splenic lymphocytes. The timing of the appearance of suppressor T-cells in the infected spleens corresponded to a loss of footpad hypersensitivity by the M. habana-infected animals.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial; D004195:Disease Models, Animal; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007111:Immunity, Cellular; D007918:Leprosy / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008815:Mice, Inbred Strains; D009161:Mycobacterium; D009164:Mycobacterium Infections / Q000276:immunology*; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial