bluuebunny/crossref_metadata_2025_split huggingface dataset:
The T cell‐specific serine proteinase TSP‐1 is associated with cytoplasmic granules of cytolytic T lymphocytes
Authors: Fruth Ulli , Prester Marlot , Golecki Jochen R. , Hengartner Hans , Simon Hans Georg , Kramer Michael D. , Simon Markus M. 
Published: March 2007

AbstractThis study describes the localization of the previously purified T cell‐specific serine proteinase, termed TSP‐1 (M. M. Simon et al., EMBO J. 1986. 5: 3267), within cytoplasmic granules of cytolytic T cell lines (CTLL). Subcellular fractionation of disintegrated CTLL (ruptured by nitrogen cavitation) was accomplished by Percoll density gradient centrifugation of cell lysates (postnuclear supernatant). Individual fractions were tested for proteinase activity on chromogenic peptide substrates and for the presence of TSP‐1 by Western blot analysis. In addition, each fraction was assayed for cytolytic activity against sheep red blood cells (SRBC), for protein and for additional marker enzymes to assess the enrichment for cellular organells. All serine enzyme‐type molecules including TSP‐1 expressed by CTLL were identified by labeling cell lysates or gradient fractions with the serine proteinase‐specific affinity ligand tritiated diisopropyl fluorophosphate ([3H]DFP) in the presence or in the absence of class‐specific or enzyme‐specific proteinase inhibitors and subsequent sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. The data demonstrate that the Percoll gradient fraction, which was shown by morphological examination in the electron microscope to be highly enriched for cytoplasmic granules, also contained > 80% of proteinase activity in addition to the granule‐associated structures cytolysin and aryl‐sulfatase. The identity of the granule‐associated proteinase in two independent cell lines, CTLL HY3‐Ag3 and CTLL 1.D.9, with the serine proteinase TSP‐1 is indicated by (a) its specificity for the chromogenic substrate H‐D‐Pro‐Phe‐Arg‐p‐nitroanilide, (b) its sensitivity to class‐specific as well as TSP‐1‐specific enzyme inhibitors and (c) by its reactivity with a polyvalent TSP‐1‐specific rabbit antiserum. Both CTLL contain a [3H]DFP‐labeled protein that migrates with a molecular mass of 60 kDa under nonreducing conditions and with 30 kDa under reducing conditions and which can be inactivated by the TSP‐1‐specific inhibitor H‐D‐Pro‐Phe‐Arg‐chloromethylketone. CTLL HY3‐Ag3 (a long‐term culture CTLL with natural killer‐like activity) but not CTLL 1.D.9 (an antigen‐specific short‐term cultured CTLL) express in addition a further [3H]DFP‐binding protein which migrates with 27 kDa under nonreducing or reducing conditions. No substrate specificity was found for this molecule. The possible function of the granule‐associated serine proteinase TSP‐1 is discussed.
Development of natural killer cells in human thymocyte culture: regulation by accessory cells
Authors: Blue Marie‐Luise , Levine Herbert , Daley John F. , Craig Kimberly A. , Schlossman Stuart F. 
Published: March 2007

AbstractIn vitro culture of human thymocytes resulted in the development of cells with natural killer (NK) activity and the acquisition of a pan‐NK antigen (NKH1) by a large number of thymocytes. The ability to kill the NK‐sensitive target, K562, was restricted to thymocytes expressing the NKH1 antigen. All NKH1+ thymocytes displayed a mature T cell phenotype, T3+T11+T8+T4−. Both the acquisition of NK activity and the development of cells with the NKH1+ phenotype could be suppressed by culturing thymocytes in the presence of adherent mononuclear cells. These results suggest that adherent accessory cells have the ability to regulate the development of T cell lineage NK cells.
Interleukin 2 pathway is autonomously activated in human T11+3−4−6−8− thymocytes
Authors: De La Hera Antonio , Toribio Maria Luisa , Marcos Miguel A. R. , Marquez Carlos , Martinez‐A Carlos 
Published: March 2007

AbstractMitogenic membrane ligands have been shown to activate interleukin 2 (IL2) production only in mature T cells, IL2 constitutive secretion having not yet been demonstrated. Here we have isolated a population of T11+3−4−6−8− human thymocytes and CD7+/T11−3−4−6−8− prothymocytes which produce and consume IL2 upon phytohemagglutinin triggering. Interestingly, their proliferation in the absence of any exogenous stimulating agent was related to an autonomous use of the IL2 system (IL2 secretion and binding to its specific receptor, whose constitutive, functional expression in human early thymocytes was recently shown). The internal activation of this system before T cell receptor acquisition stresses the relevance of the understanding of the alternative activation pathway(s) in T cell development. These findings, together with the demonstration of IL2‐promoted differentiation of human early thymocytes into mature T cells, suggest that IL2 may also be a growth and differentiation factor acting specifically early in T cell development.
Induction of human B cell proliferation and differentiation by the combination of phorbol ester and ionomycin
Authors: Roifman Chaim M. , Benedict Stephen H. , Cheung Roy K. , Gelfand Erwin W. 
Published: March 2007

AbstractPhorbol esters and Ca2+ ionophores are known to mimic intracellular messengers involved in cell activation. We studied the effects of 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) and ionomycin on tonsil and peripheral blood‐derived B lymphocytes. We show that TPA and ionomycin are co‐mitogenic and induce B lymphocyte differentiation. Although TPA in high concentrations is mitogenic to B lymphocytes by itself, submitogenic concentrations of TPA in combination with ionomycin trigger 50% of B lymphocytes to synthesize DNA. Stimulation of B lymphocytes with TPA plus ionomycin resulted in increased magnitude and a shift in the kinetics of c‐fos and c‐myc expression compared with either agent used alone. Activation markers such as the transferrin and interleukin 2 (IL 2) receptors were markedly increased after 24 h incubation with TPA and ionomycin. In parallel to the rapid proliferative burst, we observed evidence for B lymphocyte differentiation with an increase in the number of cells expressing cytoplasmic immunoglobulin (Ig) and the disappearance of the B1 surface marker. Since the cells remained surface Ig+ and secreted only small quantities of Ig, our results suggest that the combination of TPA and ionomycin is a potent inducer of B cell proliferation and early differentiation; terminal differentiation to an Ig‐secreting state, however, is not achieved.
The inflammation mediators interleukin 1 and hepatocyte‐stimulating factor are differently regulated in human monocytes
Authors: Northoff Hinnak , Andus Tilo , Tran‐Thi Thuy‐Anh , Bauer Joachim , Decker Karl , Kubanek Bernd , Heinrich Peter C. 
Published: March 2007

AbstractHuman peripheral monocytes can be induced by bacterial lipopolysaccharide to produce the inflammatory mediators interleukin 1 (IL1) and hepatocyte‐stimulating (HS) activity. IL 1 and HS activities were separated by gel permeation chromatography. It is also shown that the two monokines are differently regulated. Evidence for this stems from the finding that monocytes cultured for 24 h lose their ability to produce IL 1 in response to lipopolysaccharide, while synthesis of HS activity remains essentially unaffected.
Cytotoxic T lymphocyte clone recognizing self idiotype: its regulatory role in antibody production
Authors: Yamamoto Hiroshi , Araki Kiyonori , Bitoh Soji , Takata Masaru , Takahashi Seuchi , Fujimoto Shigeyoshi 
Published: March 2007

AbstractMOPC 104E idiotype‐specific cytotoxic T lymphocyte (CTL) clones were established. The clone KA1.02 specifically killed MOPC 104E cells and inhibited anti‐dextran antibody production in an idiotype‐specific manner. Both cytotoxicity and antibody inhibition were restricted to the cross‐reactive idiotype and class I histocompatibility antigen. The data presented here provide definitive evidence that the self idiotype is the immunogenic determinant recognized by T lymphocytes in association with the major histocompatibility complex product. A regulatory role of CTL in antibody response is proposed.
The effect of recombinant interferon‐γ on human monocyte‐derived macrophages
Authors: Jungi Thomas W. , Lerch Peter G. , Brcic Marija 
Published: March 2007

AbstractThe effect of recombinant interferon‐gamma (rIFN‐γ) on human macrophage functions was studied, using monocytes which had matured to macrophages within hydrophobic containers. Following exposure to rIFN‐γ, the number of surface‐expressed specific IgG‐binding sites was increased. This increase was restricted to high‐affinity Fc receptors (FcR), however; low‐affinity FcR were not increased in number. Exposure to rIFN‐γ led to an enhanced chemiluminescence (CL) signal in the presence of luminol and a variety of respiratory burst stimuli, such as zymosan, phorbol 12‐myristate 13‐acetate or IgG‐sensitized sheep erythrocytes (EA). In contrast, phagocytosis of EA was markedly depressed in rIFN‐γ‐treated cells. Both increase in CL response and decrease in phagocytic activity were manifest after 1 day of treatment and were more pronounced after 2 days. While 5 U/ml of rIFN‐γ was an insufficient dose, 50 to 5000 U/ml yielded significant dose‐dependent changes in both functional assays. Thus, using rIFN‐γ as a biological response‐modifier, FcR expression and FcR‐mediated CL can be dissociated from FcR‐mediated phagocytosis.
A programmed functional and phenotypic development of bone marrow‐derived cytotoxic cell precursors in vitro
Authors: Hurwitz Julia L. 
Published: March 2007

AbstractAn analysis of function and marker expression during cytotoxic cell differentiaton in vitro from T cell‐depleted bone marrow precursors is described. Cytotoxic activity is not detectable during the first five days of culture, but rises abruptly soon after. Antibody plus complement depletion studies show that cytotoxic cells derive from Thy‐1‐negative precursors and undergo a continual increase in Thy‐1 and Lyt‐2 marker expression as the culture progresses. A reciprocal decrease in asialo‐GM1 antigen expression on effector cells is seen. The J11d‐negative precursor cells acquire J11d (an antigen known to mark cortical thymocytes) at an intermediate stage of culture, but revert to the J11d‐negative phenotype prior to functional acquisition. At least some effectors are T cell receptor positive as illustrated by an anti‐T cell receptor antibody‐mediated killing assay. These patterns precisely correlate with those detected among developing T cells in vivo. Results may indicate that a programmed course of differentiation inherent to bone marrow cells may be triggered in the absence of a thymic environment.
Expression of Fcϵ receptors on activated human T lymphocytes
Authors: Prinz Jörg Christoph , Endres Nicole , Rank Gertrud , Ring Johannes , Rieber Ernst Peter 
Published: March 2007

AbstractOur results clearly demonstrate that the low‐affinity receptor for IgE (FcϵR) is an activation antigen transiently expressed on a subpopulation of human T lymphocytes. It can be selectively induced by stimulation with certain antigens or lectins, but it is not found on resting T cells. The increased numbers of activated FcϵR+ T cells observed after stimulation of peripheral blood mononuclear cells (PBMC) from bee venom allergic patients with the specific allergen phospholipase A2 (PLA2) suggest that FcϵR+ T cells might very well be involved in the regulation of the human IgE response against the respective antigen. These results were obtained by the use of two monoclonal antibodies, M‐L25 and M‐L47, which were raised against the human low‐affinity FcϵR in our laboratory. After stimulation of PBMC with phytohemagglutinin a peak of 7,6 ± 6% FcϵR+ T cells was observed on day 3, with pokeweed mitogen of 0.8 ± 0.8% on days 2 and 3, and with concanavalin A of 0.6 ± 0.7% FcϵR+ T cells on day 2. Stimulation of PBMC with tetanus toxoid (TT) induced FcϵR on maximally 0.6 ± 0.8% of the total T cells (day 4), stimulation with purified protein derivative from tuberculin (PPD) on 0.2 ± 0.6% of the T cells (day 2). In contrast to these antigens, stimulation of PBMC from bee venom allergic patients with PLA2 induced as a peak 2.5 ± 2.5% of the total T cells to express FcϵR (day 5), although the stimulated T cell population was much smaller than with TT or PPD, as was shown by their stimulation indices. The allergen‐stimulated FcϵR+ T cells were exclusively T4+. The FcϵR‐expression index was determined, which for a specific antigen or lectin correlates the percentage of FcϵR+ T cells to the stimulated T cell population, respectively.
Cyclosporin depolarizes human lymphocytes: earliest observed effect on cell metabolism
Authors: Damjanovich Sándor , Aszalós Adorján , Mulhern Sally A. , Szöllösi János , Balázs Margit , Trón Lajos , Fulwyler Mack J. 
Published: March 2007

AbstractCyclosporin A (CsA) produced dose‐dependent membrane depolarization of human peripheral blood lymphocytes. The phenomenon was investigated applying the membrane potential probe dihexyloxacarbocyanine iodide in a flow cytometer in combination with ionophores, hormones and monoclonal antibodies binding to different subclasses of lymphocytes and the anti‐interleukin 2 receptor antibody. Human interferon‐γ abolished the depolarizing effect of cyclosporin on lymphocytes. Interleukin 2 caused depolarization and also enhanced the effect of CsA. OKT4 and OKT8 monoclonal antibodies slightly hindered depolarization by CsA while OKT3, OKT11 and OKIa1 antibodies had no such effect. Valinomycin decreased CsA's effect on the membrane potential while the ionophore A‐23187 and ionomycin caused depolarizations that were additive with CsA's. CsA treatment released the isotope from 42K‐loaded human lymphocytes in a dose‐dependent fashion. CsA addition increased intracellular calcium content. CsA decreased the motional freedom of a spin probe in the membrane, but did not hinder the binding of fluoresceinated antibodies to the cell surface. These results suggest immediate alteration in membrane structure upon CsA treatment, causing potassium leakage and calcium ion uptake. These are the earliest detected effects of CsA on cells so far.
Interleukin 2 receptor traffic in a murine cytolytic T cell line
Authors: Nabholz Markus , Combe Marie‐Claire , Corthésy Patricia , Lowenthal John , Gabathuler Reinhard 
Published: March 2007

AbstractWe have analyzed different parameters of the interleukin 2 receptor (IL 2R) traffic in a murine IL2‐dependent T cell line, B6.1. These cells express about 105 IL 2R, of which approximately 10% are of high affinity (HAR). About 90% of all mature immunoprecipitable receptor molecules in the cell are on the cell surface. Measurements of the half life and of the rate of receptor synthesis indicate that these cells produce approximately 500 receptor molecules per cell and min. IL2 deprival for less than 6 h does not affect this rate.B6.1 cells internalize IL2 via their HAR only, with a maximal rate of about 500 molecules per cell and min. Among the receptors present at a given time on the cell surface, about 15% are internalized within 30 min. Receptor internalization is independent of IL2. The data obtained argue against rapid recycling of the HAR. The rate of receptor synthesis can be reconciled with the rate of IL2 internalization and the observation that internalization occurs only via HAR by assuming that cell surface low‐affinity receptors can be transformed into HAR by associating with other molecules.
B cell differentiation and interleukin 2 (IL 2): corticosteroids interact with monocytes to enhance the effect of IL 2
Authors: Emilie Dominique , Karray Saoussen , Crevon Marie‐Claude , Vazquez Aimé , Galanaud Pierre 
Published: March 2007

AbstractUpon in vitro activation by Staphylococcus aureus Cowan I strain (SAC) human peripheral blood B cells produce only marginal amounts of Ig when cultured in the presence of interleukin 2 (IL2; 10 U/ml). This response is only moderately increased by the addition of monocytes or of IL1. In the presence of dexamethasone (DM; 10−7−10−8 M) microgram amounts of both IgM and IgG are produced in co‐cultures of B cells and monocytes. This response is not modified by inhibitors of cyclooxygenase and is specifically inhibited by a monoclonal antibody interfering with the binding of IL2 to its receptor. This enhancing effect of DM is not observed in the absence of monocytes even if IL 1 is added to the cultures. Moreover, monocytes pretreated with DM stimulate the response of B cells cultures in the absence of DM. Enhancement of Ig production by DM and monocytes could be demonstrated with B cells obtained from a patient suffering from a hyperlymphocytic form of B cell type chronic lymphocytic leukemia, and in this case only IgM was produced. Importantly, DM fully inhibited the IL2‐dependent proliferation of these monoclonal B cells. Thus, physiological concentrations of DM can modulate monocytic function to enhance the differentiative effect of IL2.
A novel 90‐kDa polypeptide (Tp90) possibly involved in an antigen‐independent pathway of T cell activation
Authors: Carrel Stefan , Salvi Suzanne , Giuffrè Laura , Isler Patrick , Cerottini Jean‐Charles 
Published: March 2007

AbstractA novel surface molecule, Tp90, is described which appears to be involved in an antigen‐independent pathway of human T lymphocyte activation. The Tp90 molecule was identified by a monoclonal antibody (mAb), MX20, obtained from a fusion using spleen cells of a mouse immunized with cells from two T cell leukemia lines, Jurkat and HPB‐ALL. Biochemical data show that Tp90 is distinct and physically independent from the structures already known to be involved in T cell activation, namely T11, T44 or T3/TCR. These results were confirmed by antibody‐induced antigen modulation experiments. Modulation of Tp90 had no effect on the expression of T3 and of the T cell receptor. Conversely, the expression of Tp90 was not affected by modulation of the T3/TCR molecular complex by either anti‐T3 or anti‐TCR antibody.Functional studies showed that anti‐Tp90 mAb MX20 induced high levels of interleukin 2 production in Jurkat cells. Modulation of the T3/TCR complex significantly decreased the response of Jurkat cells to stimulation by antibody MX20, suggesting that the T3/TCR complex regulates the ability of the Tp90 molecule to induce IL2 synthesis.In addition to its effect on Jurkat cells, anti‐Tp90 mAb was found to be mitogenic for peripheral blood T cells. As the magnitude of the proliferative response elicited by anti‐Tp90 mAb was lower than that induced by anti‐T3 mAb, the possibility was considered that only a subpopulation of T cells is reactive with anti‐Tp90. Indeed as determined by FACS analyses, only 3–14% of E‐rosette‐positive cells were stained with mAb MX20. In addition, multicolor flow cytometry analysis showed that the Tp90+ cells belong preferentially to the CD8 subset.
The murine homologue of the T lymphocyte CD2 antigen: molecular cloning, chromosome assignment and cell surface expression
Authors: Sewell William A. , Brown Marion H. , Owen Michael J. , Fink Pamela J. , Kozak Christine A. , Crumpton Michael J. 
Published: March 2007

AbstractThe human T lymphocyte antigen CD2 (T11, sheep erythrocyte receptor) is expressed on all peripheral T cells and all but the most immature thymocytes. Experiments with monoclonal antibodies against CD2 suggest that CD2 is the cell surface receptor for a natural ligand involved in T cell proliferation. Clarification of the functional role of CD2 would be facilitated by the identification of CD2 in the mouse. However, antibodies that recognize the murine homologue have not been described. An alternative approach to the identification of the murine homologue was to use cross‐species DNA hybridization, employing human CD2 cDNA as a probe. Clones encoding the murine homologue were isolated from a murine T helper cell cDNA library. The murine cDNA sequence encoded a predicted mature polypeptide of 322 amino acids that showed 54% identity with the predicted human sequence. As with the human polypeptide, the cytoplasmic domain was large, and rich in proline and basic residues. CD2 mRNA was expressed in murine thymus and spleen, and in the T cell line EL4. The murine CD2 gene was assigned to chromosome 3 by Southern blot analysis of mouse‐hamster somatic cell hybrids. A rabbit antiserum raised against purified human CD2, precipitated from surface‐labeled mouse thymocytes a glycoprotein of Mr 55000–66000 which decreased to Mr35000 on digestion with endo‐β‐acetyl‐glucosaminidase F. These sizes are consistent with those predicted for the murine CD2 antigen from the cDNA sequence.
The effect on skin allograft survival of a monoclonal antibody specific for a polymorphic CD3‐like cell surface molecule in rhesus monkeys
Authors: Nooij Frans J. M. , Jonker Margreet 
Published: March 2007

AbstractFN18, a monoclonal antibody specific for the polymorphic rhesus monkey CD3 antigen on peripheral T cells, has been tested for its immunosuppressive effect in a rhesus monkey skin graft model. Animals were injected i.v. daily with antibody and they received an allogeneic skin graft two or three days after the initial antibody treatment. All animals were carefully monitored regarding levels of the major lymphocyte subsets. In animals in which RhT3 (a CD3‐like antigen) is demonstrable (i.e. FN18+ phenotype), all T cells initially disappeared from the circulation. However, T cells without RhT3 on their surface reappeared after several days, indicating that these cells must have been modulated. The survival times of the skin grafts were significantly prolonged in these animals. In monkeys in which RhT3 is not demonstrable (i.e. FN18− phenotype), mainly part of the CD4+ lymphocyte subset was depleted. Although less explicit, skin graft survival was significantly prolonged in these animals as well. In both the FN18+ and FN18− groups a difference in sensitivity between the CD4+ and CD8+ cells for the FN18 antibody could be noticed. From the data it appears that FN18 is immunosuppressive and does not have serious side effects. The data are in agreement with information available for the use of OKT3 in clinical immunosuppression. Thus, extrapolation of data from the rhesus monkey model to the clinical situation seems feasible.
Analysis of T cell responses to poly‐L(GluLys) at the clonal level. I. Presence of responsive clones in nonresponder mice
Authors: De Kruyff Rosemarie H. , Ju Shyr‐Te , Laning Joseph , Dorf Martin E. 
Published: March 2007

AbstractThe synthetic random copolymer of L‐glutamic acid and L‐lysine (GL) is weakly or nonimmunogenic in all inbred strains of mice. Theories proposed to account for nonresponsiveness to GL include a deficient T cell repertoire, failure of antigenpresenting cells to present the antigen and/or the presence of suppressor cells. In this study we examine mechanisms for nonresponsiveness to GL. We demonstrate the existence of GL‐reactive T cells which can be isolated with a relatively high frequency. These clones, which were derived following immunization of H‐2d mice with poly(LGluLLysLTyr), also respond to several GL‐containing polypeptides including the terpolymers of GL with phenylalanine, alanine (GLA) or leucine. Although recognition of GLA by heterogeneous T cell populations usually occurs in association with I‐A determinants, these clones recognize GLA, as well as the other GL‐containing polymers, in association with I‐E determinants. Analysis of the antigen and alloreactivity patterns of these clones indicated that they expressed distinct antigen receptors. These studies imply that the T cell repertoire of “nonresponder” H‐2d mice includes multiple GL‐reactive T cell clones and that the antigen‐presenting cells of these mice are effective in processing and presenting GL.