title: Role of dextran-specific suppressor T cells in the regulation of the immune response by a reactive form of dextran.
abstract: Reactive forms of antigens or haptens have been shown to induce a state of hyporesponsiveness mediated in part by suppressor T cells. Injection of Balb/c x C57B16 F1 (CB6F1) mice with a reactive form of dextran B1355S (periodate oxidized dextran, dex-P) specifically reduced responses to dextran immunization within 1 day after dex-P treatment. This unresponsiveness lasted at least 23 days and required a reactive form of dextran for its induction since native dextran and oxidized/reduced dextran failed to induce tolerance. Furthermore, hyporesponsiveness could be induced by iv injection of dextran-coupled cells, especially peripheral blood lymphocytes, a result which suggests that in vivo coupling to cellular antigens is involved in dex-P-induced hyporesponsiveness. Suppression of the anti-dextran response could be transferred to normal mice with T-cell-enriched spleen cell populations from dex-P-injected mice. Interestingly, the presence of B cells in the transferred cell preparations interfered with detection of suppression. Both Lyt 1+2- and Lyt 1-2+ cells were involved in the dex-P-induced suppression; indeed, mixtures of these types of T cells led to the most profound degree of suppression. The suppressive activity of spleen cells from dex-P-injected mice could be removed by passage over dextran-coated plates. Moreover, cells eluted from the plates specifically suppressed anti-dextran responses of normal mice, indicating that dex-P injection induces a population of antigen-binding suppressor cells. This system will allow the study of the suppressor-T-cell receptors in a well-defined idiotypic system.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000950:Antigens, Ly / Q000276:immunology; D003911:Dextrans / Q000276:immunology*; D007108:Immune Tolerance; D007116:Immunization, Passive; D007130:Immunoglobulin Idiotypes / Q000276:immunology; D051379:Mice; D010084:Oxidation-Reduction; D010504:Periodic Acid; D013329:Structure-Activity Relationship; D050378:T-Lymphocytes, Regulatory / Q000145:classification / Q000276:immunology*
chemical_list: D000950:Antigens, Ly; D003911:Dextrans; D007130:Immunoglobulin Idiotypes; D010504:Periodic Acid