bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevention of tolerance induction to a thymus‐dependent antigen by poly (A) poly (U)‐induced thymocyte fluid
Authors: Fessia Sandra L. , Kong Y.M. , Bick P.H. , Johnson A.G. 
Published: February 2007

AbstractThe prevention of tolerance induction by a thymus‐derived (T) cell factor induced with a complex of synthetic polyadenylic‐polyuridylic acid (poly (A) · poly(U)) was studied. The soluble factor(s) was obtained by exposing mouse thymocytes to poly (A) · poly(U) for 10 min, washing and culturing them for an additional 6 h in serum‐free medium. This factor in the supernatant fluid of the culture, termed AUSF, prevented tolerance induction to soluble bovine IgG (sBGG) in vivo when administered to mice 3 h after tolerogen. The effect was manifested by a marked increase in rosette formation by spleen cells and hemagglutinin titers to BGG compared with mice given sBGG only. And, as shown previously, AUSF enhanced plaque formation to red blood cells (RBC) by spleen cells in vitro. Supernatant fluids from untreated, but cultured, thymocytes showed some activity, but much less than those from poly (A) poly(U)‐stimulated cultures. AUSF was found to function across histocompatibility differences since preparations from both syngeneic and allogeneic mice were effective in interfering with tolerance induction. The data suggest that poly(A) · poly(U) prevents tolerance induction to a thymus‐dependent antigen by the early release of a T cell factor before antigen‐reactive T cells have become tolerant.
Specificity of H‐2‐linked Ir gene control in mice: recognition of defined sequence analogs of (T, G)‐A–L
Authors: Rüde E. , Günther E. , Meyer‐Delius Margot , Liehl E. 
Published: February 2007

AbstractIn order to study the specificity of H‐linked Ir gene control in more detail the polypeptide poly(LTyr, LGlu>poly(DLAla)–poly(LLys) ((T, G)‐A‐L) was modified by replacing the (T, G) copolymers by various defined tyrosine‐containing oligopeptides. It was found that the antibody response to all of the analogs of (T, G)‐A–L tested was influenced to some extent by H‐2‐linked Ir gene(s), the response pattern being concordant with that of (T, G)‐A–L. Some of the antigens carrying structurally and serologically distinct oligopeptides were as efficient with respect to high/low responder discrimination as (T, G)‐A–L, others including the core polypeptide A‐L itself were weakly immunogenic and gave only a small high/low responder split.Certain experimental data indicate that in addition to the tyrosine peptides the poly‐DL‐alanine side chains may play an important role for the recognition of these polypeptides. The possibility that the common response pattern could be due to an Ir gene specific mainly for the DL‐alanine peptides is discussed. Specificity of genetic control would then be relatively independent of the serological specificity of the tyrosine peptides. On the other hand, recognition of the analogs and of (T, G)‐A–L could be controlled by separate but closely linked Ir genes specific for each of the terminal peptide determinants which probably include the adjacent alanine residues.Genetic factors outside the H‐2 complex have in addition to the H‐linked Ir genes been found to exert a strong influence on the antibody response to some of the analogs of (T, G)‐A–L.
Idiotypic analysis of the response of C57BL/6 mice to the (4‐hydroxy‐3‐nitrophenyl)acetyl group
Authors: Jack R.S. , Imanishi‐Kari Thereza , Rajewsky K. 
Published: February 2007

AbstractStrain C57BL/6 mice produce a highly restricted primary response to the (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) group. This response is composed of molecules having μ or γ1 heavy chains and light chains of the λ type. A guinea pig anti‐idiotype was raised to the purified C57BL/6 primary anti‐NP immunoglobulin. After suitable absorption, this anti‐idiotype was shown to detect markers present on the primary anti‐NP immunoglobulin only of those strains which express the Ig‐lb allotype. Breeding experiments demonstrated that the marker segregated with the heavy chain linkage group.
Molecular structure of human histocompatibility antigens: the HLA‐C series
Authors: Snary D. , Barnstable C.J. , Bodmer W.F. , Crumpton M.J. 
Published: February 2007

AbstractThe HLA‐CW2 antigen of the B lymphoblastoid cell line BRI 8 is structurally homologous to the HLA‐A and B antigens as judged by various criteria. Each antigen comprised a glycosylated polypeptide of 43 000 molecular weight that is noncovalently associated with β2–microglobulin (β2 m). Some small differences in molecular parameters were, however, revealed. Thus, the deoxycholate‐solubilized HLA‐CW2 antigen sedimented at the same rate as the HLA‐A antigens but at a slightly faster rate than the HLA‐B antigens. This variation is apparently due to different amounts of bound deoxy‐cholate. Also, whereas essentially all of the HLA‐A and B antigens and about half of the HLA‐CW2 antigen were adsorbed Strongly by Lens culinaris lectin‐Sepharose, the remaining HLA‐CW2 antigen was bound much more weakly and did not require sugar for elution. This difference reflects some structural heterogeneity in the carbohydrate moiety of the HLA‐CW2 antigen. The results of various studies suggest that the HLA‐CW2 antigen is expressed to a lower extent than the HLA‐A or B antigens and that essentially all of the β2 m of the BRI 8 plasma membrane is associated with the HLA‐A, B and C alloantigenic polypeptides.
Mouse bone marrow‐cultured macrophage as indicator cells for mouse and human migration inhibitory factor (MIF)
Authors: Lohmann‐Matthes Marie‐Luise , Domzig W. , Meerpohl H. ‐G. 
Published: February 2007

AbstractMacrophages cultured from mouse bone marrow served as excellent indicator cells for mouse as well as for human migration inhibitory factor (MIF) preparations. The tests were performed in the capillary system and showed high reproducibility. Using mouse or human MIF‐containing supernatants, we found an inhibition of 53 % compared with the controls. Similar results were obtained if concanavalin A‐stimulated human peripheral blood lymphocytes were mixed with mouse test macrophages in a ratio of 1:5 or 1:10.
Regulation of delayed‐type hypersensitivity I. T suppressor cells for delayed‐type hypersensitivity to sheep erythrocytes in mice
Authors: Liew F.Y. 
Published: February 2007

AbstractMice injected with 1 x 108 sheep red blood cells (SRBC) into the footpad showed high levels of delayed‐type hypersensitivity (DTH) to SRBC 4‐8 days after the injection. In contrast, mice injected intravenously with 1 x 109 SRBC were unresponsive to DTH induction through 1 x 108 SRBC injected into the footpad. This suppression of DTH was maintained for at least 6 weeks and was transferable by spleen, lymph node and thymus cells to normal syngeneic recipients. Bone marrow cells, on the other hand, did not contain the suppressor cells. The suppression of DTH was antigen‐specific in that DTH to chicken red blood cells and contact sensitivity to 2,4‐dinitrofluorobenzene was not affected. The suppressor cells were theta‐positive and Ig‐negative. They appeared in the spleen in optimum number 3–4 days after induction. The suppressor cells affected both the induction and manifestation of DTH. The presence of suppressor and effector cells for DTH inducible by different routes of antigenic presentation reflects the dynamic balance in the regulation of DTH.
Thymocyte subpopulations in young and adult mice II. Study of steroid‐resistant populations by means of a specific heteroantiserum
Authors: Papiernik Martine , Bach J.F. 
Published: February 2007

AbstractMouse steroid‐resistant (Sr) cells of the thymus have been studied by means of a specific heteroantiserum. This antiserum was obtained in the rabbit after immunization with Sr thymocytes followed by absorption with high density cells isolated on a Ficoll density gradient shown to include a majority of steroid‐sensitive (Ss) cells. Antigens defined by this antiserum were found on Sr thymocytes and on a significant portion of spleen and lymph node cells, but not on Ss cortical thymocytes. Cells sensitive to this antiserum appear early in the thymus (by day 15 of gestation) at the same time as Ss cells. These results suggest (a) the existence of an autonomous Sr cell line, with its own antigenic markers appearing early in ontogeny (at the same time as Ss cells), and showing wide heterogeneity in density, possibly linked to variable degrees in maturation, and (b) the medullary origin or some peripheral lymphocytes in lymph node and spleen cells that share antigenic markers with Sr thymocytes.
Split unresponsiveness to the trinitrophenyl determinant I. Manoeuvers which suppress either humoral or cell‐mediated immune responses
Authors: Ptak W. , Różycka Danuta 
Published: February 2007

Abstract2,4,6‐Trinitrobenzene sulfonic acid (TNBS) injected intravenously (i.v.) makes mice fully tolerant to the trinitrophenyl (TNP) determinant. Administration of in vitro TNP‐labeled syngeneic erythrocytes or thymocytes renders mice unable to develop contact sensitivity to picryl chloride, while the humoral anti‐TNP responses seem to be unaffected. The reverse was found after pre‐treatment of mice with TNP‐labeled isologous IgG (MGG) since only anti‐TNP antibody responses, but not contact sensitivity to picryl chloride, were significantly reduced. TNP‐coupled macrophages given to animals suppressed both the cell‐mediated and humoral responses, and this might be due to the presence on their surface of TNP‐labeled cytophilic antibody. TNBS administered i.v. binds to circulating proteins and formed blood elements. Thus the split unresponsiveness affecting either humoral or cell‐mediated compartments after the injection of TNP‐MGG or of haptenated cells respectively, is presumably due to dissecting events which in vivo after the injection of TNBS, occur simultaneously. These results may be interpreted to indicate that split unresponsive states to TNP determinants are mediated by two independent mechanisms which require different tolerogen presentations to be triggered.
Human Ia‐like DRw lymphocyte antigens stimulating activity in primary mixed lymphocyte reaction
Authors: Fradelizi D. , Nunez‐Roldan A. , Sasportes Marilyne 
Published: February 2007

AbstractThe intenstiy of the primary mixed lymphocyte reaction (MLR) seems to be influenced by at least two distinct determinants of the HLA‐D region: the HLA‐Dw‐stimulating products and the human Ia‐like B lymphocyte DR (D‐related) antigens. In three families, the primary MLR is significantly higher in case of HLA haploidentity, when stimulating and responding cells differ with regard to both Dw and DRw determinants, than when only Dw products are different. Thus, an additional effect of DR antigens during primary MLR is observed.The role of DRw antigens in primary MLR and the results obtained by a primed lymphocyte test which can discriminate between Dw3 and DRw3, indicate that DRw and Dw products could be distinct determinants.
Blastogenic factor: its role in the mixed leukocyte culture reaction
Authors: Uotila Marjatta , Rode H. N. , Gordon J. 
Published: February 2007

AbstractThe MLC‐CML reaction depends on cooperation between different subsets of T lymphocytes in which soluble mediators may play a critical role. Evidence is presented that cell‐free supernatants from mixed cultures, containing blastogenic factor (BF) activity can, together with solubilized membrane preparations, induce a primary cell‐mediated lympholysis (CML) reaction of the same order of magnitude as intact allogeneic stimulating cells. Furthermore, BF alone can induce secondary mixed leukocyte culture (MLC) and CML reactions very efficiently. The results described suggest that BF is produced in response to activation by LD determinants, probably by helper T cells, and that the target of BF is the cytotoxic lymphocyte. It would appear that regulation of CML activity may be mediated by BF, and exhaustion of the mediator may be responsible for the decline of cell proliferation and effector function in the MLC reaction.
Regulation of delayed‐type hypersensitivity. II. Specific suppressor factor for delayed‐type hypersensitivit to sheep erythrocytes in mice
Authors: Liew F. Y. , Chan‐Liew W. L. 
Published: February 2007

AbstractAn antigen‐specific suppressor factor for delayed‐type hypersensitivity (DTH) to sheep red blood cells (SRBC) in mice is described. Lymph node cells and spleen cells from mice injected intravenously with 1 × 109 SRBC 4 days previously were incubated in vitro for 48 h in culture medium. Supernatant obtained from the culture inhibited the induction of DTH to SRBC in normal mice. It also suppressed the expression of DTH in presensitized mice. The suppression is specific as the suppressor factor had no effect on the DTH to a noncross‐reacting antigen, chicken red blood cells. Treatment of the spleen cells with anti‐theta serum and complement prevented the production of the suppressor factor, whereas treatment with anti‐Ig serum and complement had no effect. Suppressor factor produced by H‐2k mice suppressed the DTH in H‐2b mice. The factor thus seems to act across the H‐2 barrier. The suppressor factor was not removed by adsorption with goat anti‐mouse immunoglobulin immunoadsorbent, but could be adsorbed by SRBC. It was stable at 56 °C for 1 h, but was partially inactivated by freezing and thawing. The factor has a molecular weight of less than 35 000 daltons.
Grafting of triggering sites onto lymphocytes. Requirement of multivalency in the stimulation of dinitrophenyl‐modified thymocytes by anti‐dinitrophenyl antibody
Authors: Ravid A. , Novogrodsky A. , Wilchek M. 
Published: February 2007

AbstractN4‐Dinitrophenyl‐L‐2,4‐diaminobutyric acid hydrazide was coupled to aldehyde groups generated by periodate oxidation of sialyl residues on thymocytes. Anti‐2,4‐dinitrophenyl(Dnp)antibody was found to stimulate mature, hydrocortisone‐resistant thymocytes, while it had no mitogenic effect on the immature thymocytes.In order to study the involvement of different regions of the antibody molecule in the triggering process of stimulation, the mitogenicity of various antibody fragments was also assessed. The divalent F(ab')2 was found to be a superior mitogen compared to the intact antibody when added to Dnp‐conjugated thymocytes. The monovalent Fab' and Fab fragments have no mitogenic activity indicating that cross‐linkage may be a prerequisite for stimulation.
Activation of the alternative complement pathway by human B cell lymphoma lines is associated with Epstein‐Barr virus transformation of the cells
Authors: McConnell I. , Klein G. , Lint T. F. , Lachmann P. J. 
Published: February 2007

AbstractActivation of the alternative complement pathway by human B cell lymphoma lines is correlated with the presence of Epstein Barr virus (EBV) in the cell genome. EBV‐negative B cell lymphoma lines produce little activation of the alternative pathway as measured either by C3 deposition on the cell surface or C3 conversion and consumption of alternative pathway activity in the supernatant serum. By contrast, EBV‐positive sublines derived by in vitro EBV conversion of EBV‐negative parental lines produce considerable activation of the alternative pathway. This membrane‐associated complement‐activating mechanism reflects an EBV‐induced membrane change in these cells and may provide a mechanism where by EBV‐transformed cells are controlled in vivo.
Differentiation antigens in rat lymphocyte subpopulations recognized by rabbit antisera against electrophoretically separated cells
Authors: Zeiller K. , Pascher Gertrud 
Published: February 2007

AbstractRat lymphocytes of high (H cells) and low (L cells) electrophoretic mobility (EPM) from lymph node (LN), spleen (Spl) and thymus (Thy) were separated by free flow electrophoresis and antisera against these cells raised in rabbits. Eight distinct lymphocyte‐specific xenoantigens could be characterized by appropriate cross‐absorption of three antisera: anti‐Thy‐L cell IgG, anti‐LN/‐Spl‐H cell IgG and anti‐LN/Spl‐L cell IgG. Cross‐absorption of anti‐Thy‐L cell IgG with unseparated LN or Spl cells revealed a thymus‐specific antigen complex which was absent from peripheral rat lymphocytes but present on mouse thymocytes and peripheral T cells. This complex could be further separated into brain‐associated and nonassociated antigens. The brain‐associated antigens consisted of a rat‐specific component, a component shared by the rat and all mice which carry the Thy‐1.1 and Thy‐1.2 allogenic specificity, and a third component shared by rat and Thy‐1.1 mice. This Thy‐1 antigen complex showed a 26‐fold larger antibody‐binding capacity to thymocytes of low EPM than to those of high EPM. The thymic antigens which were not absorbed by brain tissue showed similar antibody‐binding capacity to all thymocytes whether of low or high EPM. Anti‐LN/Spl‐H cell IgG cross‐absorbed with LN/Spl‐L cells detected antigens which were localized on all rat peripheral H cells and thymocytes but which were absent from peripheral L cells. Further absorption with Thy‐L cells revealed a distinct subclass of antigens present on peripheral H cells and Thy‐H cells but absent from Thy‐L cells. On the other hand, cross‐absorption of anti‐LN/Spl‐L cell IgG with peripheral H cells provided specificities which were directed against all peripheral L cells but which did not react with peripheral H cells and thymocytes. The relationship of these different xenoantigens to known lymphocyte subpopulations is discussed.
Clearance and re‐expression of a myeloma cell's antigenbinding receptors induced by ligands known to be immunogenic or tolerogenic for normal B lymphocytes: a model to study membrane events associated with B cell tolerance
Authors: Bankert R. B. , Mayers G. L. , Pressman D. 
Published: February 2007

AbstractWe have previously reported that the immune response of BALB/c mice to α(1→3) linkage groups of dextran B1355 and the in vivo growth of MOPC 104E tumor cells were specifically suppressed by the administration of oxidized dextran B1355. In the present study, we report on membrane events that occur after 104E cells are incubated with either the native dextran B1355 or the oxidized dextran B1355. The 104E cells, which possess membrane‐associated receptors that are specific for the α(1→3) linkage groups of dextran, were monitored for the clearance of receptor‐antigen complexes, and the subsequent re‐expression of receptors that follow the interaction of cells with either the native ligand, dextran, or the suppressor ligand, oxidized dextran. Following incubation of 104E cells with the native ligand, complexes of dextran plus receptors aggregate and are gradually cleared (2–4 h) from the membrane. Subsequent to the receptor‐antigen clearance induced by the native ligand, a second set of dextran‐binding receptors is observed. The second set of receptors appears to be derived from a presynthesized precursor pool of receptors within the cell and not from the synthesis of new receptors. These receptors appear diffusely over the entire surface of the cell membrane as opposed to a single discrete area within the membrane. The receptors remain within the membrane for at least 48 h unless perturbed again by antigen. Re‐expression of receptors is not observed following a second perturbation with the native ligand.The membrane events which succeed the incubation of the 104E cells with the suppressor ligand differ significantly from those which are observed following incubation with the native ligand. Exposure to the suppressor ligand results in a rapid (10–30 min) and complete clearance of the complexes of oxidized dextran plus receptor from the membrane of the 104E cell, and the clearance of these complexes occurs without any detectable receptor aggregation. The most significant difference observed following the pulse with the suppressor ligand is the complete absence of a receptor re‐expression. Thus, 104E cells, following a brief pulse with oxidized dextran, fail to incorporate the presynthesized second set of receptors into the plasma membrane. This apparent suppressive signal occurs without any detectable change in cell viability.The inability of the 104E cell to express a second set of antigen‐binding receptors following a suppressor antigen‐induced clearance of the first set is presented as a possible link of a membrane event with an alteration in cell function (i.e. suppression of proliferation of the 104E cell in vivo by this antigen). The possible relationship of the 104E cell membrane events to normal B cell membrane events associated with immunity or tolerance is discussed.
Influenza virus‐specific cytotoxic T cells in man; induction and properties of the cytotoxic cell
Authors: McMichael A. J. , Askonas Brigitte A. 
Published: February 2007

AbstractHuman peripheral blood lymphocytes have been sensitized in vitro to influenza virus antigen. After an induction period of 4–14 days, cytotoxic cells which lyse autologous influenza virus‐infected lymphoid cells could be demonstrated. The cytotoxic cell is a T lymphocyte which shows specificity for sensitizing influenza virus type A or B. It cannot distinguish between major subtypes of influenza A virus. The use of virus‐infected normal lymphoid cells as target cells overcame the difficulties of nonspecific killing encountered with some transformed cells.
Immune depression in trypanosome‐infected mice I. Depressed T lymphocyte responses
Authors: Pearson T. W. , Roelants G. E. , Lundin Lena B. , Mayor‐Withey Kathleen S. 
Published: February 2007

AbstractUsing a wide range of experimental conditions, several kinds of T lymphocyte responses in spleen cell populations from trypanosome‐infected mice were studied. Lymphocyte stimulation after culture with the mitogen concanavalin A or with histoincompatible cells differing at H‐2 or minor lymphocyte‐stimulating loci was reduced or abolished in spleen cells from infected mice when compared with responses of spleen cells from uninfected controls. In addition, cytotoxic lymphocytes were not generated in mixed lymphocyte cultures which contained spleen cells from infected animals. Allogeneic skin grafting experiments performed with normal and infected mice showed that a decreased T lymphocyte response also occurs in vivo. The depressed immune responses were not simply due to low numbers of T lymphocytes in spleens of infected animals, but reflected a generalized immune depression which was not antigen‐specific.
Chemiluminescence and immune cell activation I. Early activation of rat thymocytes can be monitored by chemiluminescence measurements
Authors: Wrogemann K. , Weidemann M. J. , Peskar B. A. , Staudinger H. , Rietschel E. T. , Fischer H. 
Published: February 2007

AbstractImmediately after the addition of concanavalin A, rat thymocytes respond, in the presence of luminol, with a burst of chemiluminescence (CL) that can be conveniently monitored in an ordinary liquid scintillation spectrometer. Peak CL is reached after 50 sec. Addition of catalase suppresses 65% of the CL, suggesting that H2O2 generation may be its major source. CL with different kinetic characteristics can also be generated by the calcium ionophore A23187.Our rat thymocytes contain approximately 0.1% endogenous macrophages. Bone marrow‐derived rat macrophages also respond to concanavalin A or A23187 stimulation with a burst of CL. However, the kinetic properties of CL as well as the inhibition of CL by catalase in these cells differ markedly from those of thymocyte preparations, suggesting that the major portion of the CL in rat thymocytes actually originates in T lymphocytes.Because CL measurements allow the monitoring of very early events in cell activation and because of the simplicity of the technique, CL measurements may become a useful method for the study of lymphocyte activation, of macrophage‐lymphocyte interactions, as well as for the rapid screening for specificity and reactivity of T lymphocyte populations.