02484nas a2200313   4500000000100000008004100001260001300042653001200055653002400067653002700091653003000118653002300148653001200171653002600183653000900209653002500218653001800243653002900261653001100290653003000301100001500331700001600346245007700362856007800439300001200517490000700529520162000536022001402156       1979                            d  c1979 Aug10aAnimals10aAntigens, Bacterial10aDisease Models, Animal10aHypersensitivity, Delayed10aImmunity, Cellular10aleprosy10aLymphocyte Activation10aMice10aMice, Inbred Strains10aMycobacterium10aMycobacterium Infections10aSpleen10aT-Lymphocytes, Regulatory1 aWatson S R1 aCollins F M00aDevelopment of suppressor T-cells in Mycobacterium habana-infected mice.  uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC414480/pdf/iai00188-0021.pdf  a497-5060 v253 a<p>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.</p>  a0019-9567