Jenkins M K, Miller S D
Department of Microbiology-Immunology, Northwestern University Medical School, Chicago, IL 60611.
J Mol Cell Immunol. 1985;2(1):1-13.
Recent advances in the biochemical and genetic analysis of soluble immunoregulatory molecules (TsF) have been achieved via the establishment of cloned TsF-producing T cell hybridomas. However, studies on in vivo regulation of immune responses have been hampered by the lack of clonal populations of nontransformed suppressor T cells (Ts). Nonhybridoma Ts clones would allow cellular dissection of complex Ts circuits and precise analyses of Ts effector mechanisms. Our laboratory has recently demonstrated that poly(Glu60Ala30Tyr10) (GAT)-specific unresponsiveness is induced in adult responder mice tolerized via the intravenous injection of GAT-coupled syngeneic spleen cells (GAT-SP). This unresponsiveness is mediated by two antigen-specific mechanisms--nontransferable clone inhibition and induction of transferable Ts which regulate both humoral and T cell-mediated delayed-type hypersensitivity (DTH) responses. We have thus applied methodology used for the production and maintenance of antigen-specific T helper (Th) clones in an attempt to establish and characterize Ts clones mediating GAT-specific in vivo suppressive activity. Therefore, spleen cells from GAT-SP tolerant responder mice were maintained in continuous culture with soluble GAT, 10% concanavalin A-conditioned medium (IL-2), and irradiated syngeneic antigen presenting cells (APC). A stable, long-term Ts cell line (J372) was isolated by this procedure. This line and one of its clones (J372.2) suppressed the afferent (induction), but not efferent (elicitation) phase of GAT-specific DTH. In contrast, the J372.2 Ts clone had no inhibitory effect on the development of specific T cell proliferative responses. Intravenous injection of small numbers (2-5 x 10(6)) of J372.2 Ts cells resulted in significant suppression of DTH responses in GAT-primed, but not in ovalbumin- or methylated bovine serum albumin-primed recipients, demonstrating the antigen-specificity of the suppression. Intravenous injection of a GAT-specific Th clone (JTL-E1) or of a DNP-specific Th line (JTL-DNP) had no suppressive effects on GAT-specific responses suggesting that J372.2-mediated unresponsiveness is the result of active suppression, and not the result of nonspecific inhibitory effects of activated T cells. More importantly, normal GAT-specific DTH responses in recipients of the JTL-E1 Th clone (maintained in the same GAT concentration as J372.2) indicated that J372.2-mediated suppression was not due to induction of nontransferable tolerance by surface-associated GAT.(ABSTRACT TRUNCATED AT 400 WORDS)
通过建立产生可溶性免疫调节分子（TsF）的克隆T细胞杂交瘤，在可溶性免疫调节分子（TsF）的生化和遗传分析方面取得了最新进展。然而，由于缺乏未转化的抑制性T细胞（Ts）的克隆群体，对免疫反应的体内调节研究受到了阻碍。非杂交瘤Ts克隆将允许对复杂的Ts回路进行细胞剖析，并精确分析Ts效应机制。我们实验室最近证明，通过静脉注射GAT偶联的同基因脾细胞（GAT-SP）使成年反应小鼠耐受后，可诱导其对聚（Glu60Ala30Tyr10）（GAT）产生特异性无反应性。这种无反应性由两种抗原特异性机制介导——不可转移的克隆抑制和可转移Ts的诱导，后者调节体液免疫和T细胞介导的迟发型超敏反应（DTH）。因此，我们应用了用于产生和维持抗原特异性T辅助（Th）克隆的方法，试图建立并表征介导GAT特异性体内抑制活性的Ts克隆。因此，将来自GAT-SP耐受反应小鼠的脾细胞与可溶性GAT、10%伴刀豆球蛋白A条件培养基（IL-2）和经照射的同基因抗原呈递细胞（APC）一起进行连续培养。通过该程序分离出了一个稳定的长期Ts细胞系（J372）。该细胞系及其一个克隆（J372.2）抑制了GAT特异性DTH的传入（诱导）阶段，但不抑制传出（激发）阶段。相比之下，J372.2 Ts克隆对特异性T细胞增殖反应的发展没有抑制作用。静脉注射少量（2 - 5×10⁶）的J372.2 Ts细胞可显著抑制GAT致敏受体的DTH反应，但对卵清蛋白或甲基化牛血清白蛋白致敏受体则无此作用，这证明了抑制作用的抗原特异性。静脉注射GAT特异性Th克隆（JTL-E1）或DNP特异性Th系（JTL-DNP）对GAT特异性反应没有抑制作用，这表明J372.2介导的无反应性是主动抑制的结果，而不是活化T细胞非特异性抑制作用的结果。更重要的是，JTL-E1 Th克隆受体（在与J372.2相同的GAT浓度下维持）的正常GAT特异性DTH反应表明，J372.2介导的抑制不是由于表面相关GAT诱导的不可转移耐受性。（摘要截短于400字）
