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M H Dietz

Publications and source records attributed to M H Dietz.

6 recordsLinked to original sources
PubMed1981

Antigen- and receptor-driven regulatory mechanisms. VII. H-2-restricted anti-idiotypic suppressor factor from efferent suppressor T cells.

Azobenzenearsonate (ABA)-specific T cell-derived suppressor factor (TsF1) from A/J mice was used to induced second-order suppressor T cells (Ts2). Comparison of suppressor T cells induced by antigen (Ts1) with Ts2 induced by TsF1 revealed that Ts1 were afferent suppressors active only when given at the time of antigen priming, and not thereafter, whereas Ts2 could act when transferred at any time up to 1 d before antigen challenge for a delayed-type hypersensitivity response. This was true even when the recipient could be shown to be fully immune before transfer of Ts2, thus defining these cells as efferent suppressors. The anti-idiotypic specificity of the Ts2 was demonstrated by the ability of Ts to bind to idiotype (cross-reactive idiotype [CRI])-coated Petri dishes. A soluble extract from Ts2 (TsF2) was also capable of mediating efferent suppression that was functionally antigen- (ABA) specific. Comparison of TsF1 with this new factor, TsF2, revealed that both lack Ig-constant-region determinants, possess H-2-coded determinants, and show specific binding (to ABA and to CRI+-Ig, respectively). TsF1 acts in strains that differ with respect to H-2 and background genes, whereas TsF2 shows H-2- and non-H-2-linked genetic restrictions. This existence of H-2 restriction of TsF2 activity suggests that the apparent discrepancies in studies of H-2 restriction of TsF may be a result of the analysis of two separate classes of TsF, only one of which shows genetically restricted activity, thus unifying several models of suppressor cell activity.

Animals↗
PubMed1980

Antigen- and receptor-driven regulatory mechanisms. V. The failure of idiotype-coupled spleen cells to induce unresponsiveness in animals lacking the appropriate VH genes is caused by the lack of idiotype-matched targets.

A/J anti-p-azobenzenearsonate (ABA) antibodies bearing cross-reactive idiotypic (CRI) determinants, when coupled to spleen cells and then injected intravenously into naive animals, stimulate suppressor T cell (Ts) responses. Moreover, previous studies have demonstrated that the ability of such idiotype-coupled spleen cells to induce immune unresponsiveness to subsequent immunization with ABA-coupled spleen cells is linked to Igh-1 genes. Thus, CRI bearing antibodies from A/J mice, when conjugated to normal BALB/c spleen cells in vitro and then injected intravenously to syngeneic BALB/c mice, failed to induce tolerance in these animals. However, spleen cells taken from these animals transferred significant degrees of suppression to Igh-1 congenic C.AL-20 but not to H-2 congenic, Igh-1 distinct B10.D2 mice. Therefore, the failure of CRI-coupled spleen cells to induce suppressor cell- mediated unresponsiveness in animals unable to express the appropriate VH genes (i.e. BALB/c and B10.D2) appears to be caused by the lack of idiotype- matched targets. The notion that the ability to express certain Vn genes in the recipient animal is a prerequisite for suppressor cell function was further supported by the observation that suppressor cells induced in C.AL-20 mice failed to transfer any degree of suppression to BALB/c mice. The ability to transfer suppression from BALB/c mice to C.AL-20 mice is a T cell- dependent phenomenon, since in vitro treatment with anti-Thy 1.2 antiserum and complement completely abrogated suppressor cell function. Furthermore, these suppressor T cells are antigen specific and can be enriched on idiotype-coated petri dishes, indicating they possess anti-idiotypic receptors. Therefore, appropriate anti-idiotype and idiotype interaction is essential for the manifestation of suppressor T cell function in ABA-specific suppressor pathways.

Animals↗
PubMed1980

Antigen- and receptor-driven regulatory mechanisms. IV. Idiotype-bearing I-J+ suppressor T cell factors induce second-order suppressor T cells which express anti-idiotypic receptors.

Administration of azobenzenearsonate (ABA)-coupled syngeneic spleen cells intravenously to A/J mice leads to the generation of suppressor T cells (Ts1) which exhibit specific binding to ABA-bovine serum albumin (BSA)-coated dishes. These Ts1 share idiotypic determinants with the major cross-reactive idiotype (CRI) of the anti-ABA antibodies of A/J mice, and also produce a soluble suppressor factor (TsF) bearing CRI and I-J subregion-coded determinants. Injection of this TsF into naive A/J mice elicits a second set of specific suppressor cells (Ts2) which are not lysed by anti-CRI antibody plus C, and which do not bind to ABA-BSA-coated dishes. However, in contrast with Ts1, these Ts2 do bind to plates bearing CRI+ anti-ABA immunoglobulin. Thus, Ts2 exhibit anti-idiotypic specificity. These data indicate that antigen elicits the production of a soluble T cell product bearing both variable portion of the Ig heavy chain (VH) and I-J subregion-coded determinants which serves to communicate between T cell subsets to establish an idiotype-anti-idiotype regulatory pathway.

Animals↗
PubMed1980

Antigen and receptor-driven regulatory mechanisms. VI. Demonstration of cross-reactive idiotypic determinants on azobenzenearsonate-specific antigen-binding suppressor T cells producing soluble suppressor factor(s).

The first detectable suppressor T cell (Ts) arising after i.v. administration of azobenzenearsonate- (ABA) conjugated syngeneic spleen cells to A/J mice has been studied for its receptor specificity and ability to produce soluble suppressor factor(s). This cell, termed Ts1, has a specific receptor for the eliciting antigen ABA, as demonstrated by selective binding to ABA protein- but not TNP protein-coated plastic dishes. The activity of ABA-Ts1 can be abrogated by treatment with anti-idiotypic antibodies made against anti-ABA antibodies of A/J mice (anti-CRI), indicating that these ABA-binding cells possess a surface receptor structure sharing idiotypic determinants with antibodies of the same specificity. Finally, soluble extracts from, antigen-adherent ABA-Ts1, but not nonadherent cells from the same spleen cell population, possess suppressive activity when assayed directly for afferent suppression or tested for their ability to trigger a second population of Ts (Ts2) in naive recipients. These findings demonstrate a close concordance between a T cell surface receptor, soluble T suppressor factors, and B cell derived antibody, all capable of direct recognition of the eliciting ABA antigen.

Animals↗