Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0017636 (glioblastoma)
18,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capacity of three different human glioblastoma cell lines to activate human T cells was analysed by measuring major histocompatibility complex (MHC) antigen expression, monokine secretion and lectin, mAb OKT3 and antigen-driven T cell proliferation. All glioblastoma cells tested were able to induce PHA and concanavalin A (ConA)-driven T cell proliferation in a dose-dependent fashion, while all failed to induce T cell activation with mAb OKT3. In addition, the glioblastoma cell line 86HG39 was able to induce tetanus toxoid and toxoplasma lysate antigen-specific T cell proliferation. The responding T cell lines originated from only one out of five different donors. This foreign antigen-specific T cell proliferation induced by 86HG39 cells could be inhibited with mAb L243 directed against HLA-DR molecules. The study of monokine secretion by 86HG39 cells showed a strong interleukin (IL)-6 secretion after lipopolysaccharide (LPS) treatment, whilst no IL-1 secretion was observed. Furthermore, only 86HG39 cells were positive for HLA-DR molecules, whereas interferon (IFN) gamma treatment of 87HG28 and 87HG31 cells was necessary for the induction of class II antigen expression. Thus, cell line 86HG39 shows many features of an antigen presenting cell and the interaction of these cells with MHC compatible human T cells might be a useful model to study cellular immune reactions within the central nervous system.
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PMID:Human glioblastoma cell line 86HG39 activates T cells in an antigen specific major histocompatibility complex class II-dependent manner. 146 90

For the past several years immunologists have been fascinated by a series of experiments showing that transforming growth factor beta (TGF beta) suppresses T- and B-lymphocyte growth as well as IgM and IgG production by B cells. Moreover, while exerting chemotactic activity on monocytes and inducing expression of interleukin-1 and interleukin-6 by these cells, TGF beta interferes with bacterially induced tumor necrosis factor alpha production, oxygen radical formation and the adhesiveness of granulocytes to endothelial cells. These mechanisms may provide the basis for the effect of TGF beta to prevent the microvascular changes associated with brain edema formation in bacterial meningitis. Given the potential of lymphocytes as well as macrophages to produce TGF beta 1, this cytokine may exert negative feedback signals on the immune response, provided the cytokine is processed from its latent form to the bioactive homodimer. Potent effects of TGF beta have been observed in experimental animals including the inhibition of the generation of virus-specific cytotoxic T cells and antiviral antibodies as well as the diminution of cellular infiltrates with decreased major histocompatibility complex class-II expression and CD8+ T cells in the tissue of virally infected animals. TGF beta may also be of importance in tumor immunology. By the production of bioactive TGF beta as detected in glioblastoma and acute T-cell leukemia, tumor cells may induce an immunodeficiency state and escape immune surveillance. In inflammation, monitoring of TGF beta in the tissue will bring light on the immune regulation in acute and chronic inflammatory diseases.
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PMID:Modulation of the immune response by transforming growth factor beta. 148 57

The host's immune system discriminates tumor cells from normal cells by recognizing the major histocompatibility complex (MHC) class I antigen expressed on the tumor cell membrane. However, the role of MHC class I antigen in tumor cells has not yet been clarified. In this study, the influence of MHC class I antigen expression on the tumorigenicity of a human glioblastoma cell line (KMG4) is examined. Barely detectable levels of MHC class I messenger ribonucleic acid were found to express in KMG4 cells by Northern blot analysis using mouse MHC class I (H-2Ld) and human leukocyte antigen (HLA)-B7 genes as probes. The H-2Ld gene connected at the downstream end of murine mammary tumor virus (MMTV)-promoter was cotransfected with the neomycine-resistant gene pSV2-neo into KMG4 cells, and the drug-resistant cells were selected. The KMG4 cells (KMG4-MMTV-Ld), which acquired the MHC class I gene were detected by Northern blot analysis with H-2Ld as the probe, and by immunohistochemistry using the H-2Ld-specific monoclonal antibody. Tumorigenicity, as determined by colony-forming ability in soft agar, was then compared between MHC class I-expressing KMG4-MMTV-Ld and nonexpressing control cells. The MHC class I-expressing cells were found to be deprived of colony-forming ability, indicating that MHC class I antigen could negatively influence the anchorage-independent cell growth of the human glioblastoma cell line KMG4.
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PMID:Suppression of anchorage-independent growth of human glioblastoma cell by major histocompatibility complex class I gene-transfection. 156 45

Interferon-gamma-induced tryptophan metabolism of human macrophages was compared to ten human neoplastic cell lines of various tissue origin and to normal dermal human fibroblasts. Tryptophan and metabolites were determined in supernatants of cultures, after incubation for 48 h, by high-performance liquid chromatography with ultraviolet and fluorescence detection. With the exception of two cell lines (Hep G 2, hepatoma and CaCo 2, colon adenocarcinoma) in all of the ten other cells and cell lines tryptophan degradation was induced by interferon-gamma. Five of these ten formed only kynurenine (SK-N-SH, neuroblastoma; T 24, J 82, bladder carcinoma; A 431, epidermoid carcinoma; normal dermal fibroblasts), three formed kynurenine and anthranilic acid (U 138 MG, glioblastoma; SK-HEP-1, hepatoma; A 549, lung carcinoma). Only one line, A 498 (kidney carcinoma) showed the same pattern of metabolites as macrophages (kynurenine, anthranilic acid and 3-hydroxyanthranilic acid). Interferon-gamma regulated only the activity of indoleamine 2,3-dioxygenase. All other enzyme activities detected were independent of interferon-gamma, as shown by the capacity of the cells to metabolize L-kynurenine or N-formyl-L-kynurenine. Increasing the extracellular L-tryptophan concentration resulted in a marked induction of tryptophan degradation by macrophages. Contrarily, a significant decrease of the tryptophan degrading activity was observed when the extracellular L-tryptophan concentration was increased 2-fold with SK-N-SH, T 24 and J 82, 4-fold with A 431 and A 549 and 10-fold with U 138 MG and SK-HEP-1. The activity was unaffected by extracellular L-tryptophan with dermal fibroblasts and A 498. Though interferon-gamma was the most potent inducer of tryptophan metabolism, interferon-alpha and/or -beta showed small but distinct action on some of the cells. In all cells which reacted to interferon-gamma by enhanced expression of class I and/or class II major histocompatibility complex antigens tryptophan degradation was also inducible. These results demonstrate that induction of indoleamine 2,3-dioxygenase is a common feature of interferon-gamma action, that the extent of this induction is influenced by extracellular L-tryptophan concentrations and that indoleamine 2,3-dioxygenase is the only enzyme in the formation of 3-hydroxyanthranilic acid from tryptophan which is regulated by interferon-gamma.
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PMID:Characteristics of interferon induced tryptophan metabolism in human cells in vitro. 250 Sep 76

A procedure for enrichment in recombinant interleukin-2 (rIL2)-activated natural killer (NK) cells was developed and used for in vitro generation of antitumor effector cells from the peripheral blood of 20 patients with central nervous system (CNS) tumors. In comparison to the patients' unseparated mononuclear cells and nonadherent lymphocytes cultured in the presence of 1000 U/ml of rIL2 for up to 3 weeks, interleukin-2-stimulated lymphoid cells, when purified by adherence to plastic, proliferated better (up to 6,720-fold expansion) and achieved up to five times higher levels of antitumor activity against K562 cell targets and NK-resistant glioblastoma cell targets. Two-color flow cytometry analysis showed that cultures of cells purified by adherence to plastic which had the best proliferation contained 10% or less of CD3+Leu19- T-lymphocytes, while the unseparated lymphokine-activated killer cell cultures which proliferated poorly contained up to 85% of CD3+Leu19- T-cells. Cultures of adherent lymphocytes which reached the highest antitumor cytotoxicity were enriched in CD3+Leu19+ effectors (60-80%); the proportion of CD3-Leu19+ NK-cells was not greater than 25% in these cultures. Thus, using the technique of 24- or 48-h activation in rIL2 and adherence to plastic, and in contrast to the results obtained with cells from normal donors, it was not possible to enrich in activated NK cells from the blood of patients with CNS tumors. Instead of activated NK cells, a population enriched in non-major histocompatibility complex-restricted cytotoxic T-cells (CD3+Leu19+) was obtained in cultures from most but not all patients. Low NK cell activity and elevated numbers of circulating CD3+Leu11+ cells seen in the blood of these patients, previously treated by surgery/radiation/chemotherapy and maintained on steroids, could be responsible for the preferential adherence and subsequent expansion to plastic of IL2-activated non-major histocompatibility complex restricted cytotoxic T-lymphocytes.
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PMID:In vitro generation and antitumor activity of adherent lymphokine-activated killer cells from the blood of patients with brain tumors. 297 33

We examined the effect of human foamy virus (HFV) infection on the expression of human major histocompatibility complex molecules. Our data show that in vitro HFV infection of U373-MG glioblastoma cells results in increased expression of class I human leukocyte antigen (HLA) and transcripts. Transient transfection assays of plasmids containing the reporter gene chloramphenicol acetyl transferase driven by different 5' deletions of the HLA-A11 class I promoter allowed identification of cis-acting elements involved in this regulation. HFV infection has two opposite effects on the HLA class I promoter: transactivation of the HLA-A11 promoter through a positive regulatory element located in the -525 to -335 region upstream of exon 1 and down-regulation of transcriptional activity driven by the -335 to -205 class I promoter region. Additional experimental data indicate that the effect of HFV on HLA class I expression is not mediated by the interferon pathway.
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PMID:Human foamy virus infection activates class I major histocompatibility complex antigen expression. 753 15

Interferon-gamma (IFN-gamma) is a potent immune regulatory cytokine and is, in addition, involved in the induction of antiparasitic effector mechanisms in different cell types. The first step of IFN-gamma action is its binding to a specific receptor. Furthermore, it has been shown that IFN-gamma binds with a great affinity to the heparin-like structure of heparan sulfate, which is localized in basement membranes and on cell surfaces. In this study, we analyze the effect of heparin and heparan sulfate on three different IFN-gamma-mediated activities inducible in human glioblastoma cells (87HG31 and 86HG39). We find firstly that heparin is able to inhibit IFN-gamma-mediated induction of major histocompatibility complex (MHC) class II antigen expression on 87HG31 cells, an effect which can be abrogated by protamine. Secondly, we show that heparin inhibits the IFN-gamma-induced toxoplasmostasis within 86HG39 cells in a dose-dependent fashion, and thirdly that heparin inhibits the IFN-gamma-mediated induction of the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase. In contrast to IFN-gamma-induced effects, the activity of other cytokines, such as interleukin (IL)-1, IL-2 and IL-6, is not influenced by heparin. The possible mechanism of heparin-induced inhibition of IFN-gamma is discussed.
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PMID:Heparin inhibits the antiparasitic and immune modulatory effects of human recombinant interferon-gamma. 770 97

This study investigates a new approach to adoptive therapy of glioblastoma using as antitumor effector a potent major histocompatibility complex nonrestricted killer clone (TALL-104) established from a patient with acute T-lymphoblastic leukemia. The human glioblastoma cell line U-87 MG could be successfully engrafted in mice with severe combined immunodeficiency using the i.p., intracerebral, and s.c. routes. The latter model was elected to evaluate therapy based on its high reproducibility. Tumor growth in mice engrafted s.c. was proportionally associated with splenomegaly and leukocytosis. Multiple transfers of lethally irradiated (non-proliferating) TALL-104 cells at the tumor site resulted in about 50-70% inhibition of tumor growth as compared to untreated mice, with concomitant reduction of splenomegaly and leukocytosis. The antitumor effects were inversely proportional to the size of the tumor at initiation of therapy, 90-100% inhibition occurring in severe combined immunodeficiency mice treated from the day of U-87 MG challenge. Neither splenomegaly nor leukocytosis developed in animals in which tumor growth was completely blocked. Stimulation of TALL-104 cells with either interleukin 2 or interleukin 12 prior to irradiation and adoptive transfer increased the antitumor efficacy of the killer cells to about the same extent. The potential usefulness of irradiated TALL-104 cells in adjuvant therapy against glioblastomas and other well-localized tumors is discussed.
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PMID:Treatment of experimental glioblastoma with a human major histocompatibility complex nonrestricted cytotoxic T cell line. 780 48

We studied the effect that treating two types of glioblastoma cell lines, U-87 MG and U-251 MG, with interferon (IFN)-gamma had on their susceptibility to lysis by lymphokine-activated killer (LAK) cells. We also examined the participation of cell-adhesion molecules and major histocompatibility complex (MHC) class I and II antigens present on the target cells in lysis by LAK cells. Treatment with IFN-gamma (1000 U/ml) for 48 hours resulted in the increased expression of both intercellular-adhesion molecule 1 and MHC class I antigens on tumor cells. In addition, untreated tumor cells expressed neural-cell-adhesion molecules and MHC class II antigens highly, but their expression was not affected by IFN-gamma treatment. These changes in expression were accompanied by a decreased susceptibility to lysis by LAK cells. Treatment with antisense-intercellular-adhesion molecule-1 oligonucleotide further inhibited LAK lysis of target cells, following treatment with IFN-gamma. In contrast, acid treatment of tumor cells after treatment with IFN-gamma increased their susceptibility to lysis by LAK cells. These findings suggest that treatment of glioblastoma cells with IFN-gamma decreased their susceptibility to lysis by LAK cells, and that this decrease in susceptibility is attributable principally to the increased expression of MHC class I antigen on target cells.
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PMID:Interferon-gamma induces a decrease in the susceptibility of human glioma cells to lysis by lymphokine-activated killer cells. 793 31

As part of continuing studies to investigate the possible regulatory effects of cytokines on malignant astrocytes, we investigated the effects of interleukin-4 (IL-4) alone and in combination with tumor necrosis factor-alpha (TNF alpha) and/or interferon-gamma (IFN gamma) on the cell growth and major histocompatibility complex (MHC) antigen expression of a cloned human glioblastoma cell line (9C). The 9C cells were treated with IL-4 alone or in combination with TNF alpha and/or IFN gamma and were examined for proliferation by crystal violet assay and for Class II MHC antigen by flow cytometry. Results indicated that IL-4 alone did not affect 9C proliferation. In combination with TNF alpha or IFN gamma, however, IL-4 significantly and dose-dependently inhibited cell growth. As previous reports have shown, TNF alpha combined with IFN gamma exerted an additive growth suppressive effect on glioblastoma cells, probably by enhancing TNF receptor expression. This additive effect of TNF alpha and IFN gamma was further enhanced by IL-4. In contrast, IL-4 did not modulate expression of Class II MHC antigen on 9C cells, even in combination with IFN gamma, which predictably enhanced this antigen. These results suggest that IL-4 is capable of modulating glioblastoma growth only in the presence of other cytokines, such as TNF alpha and/or IFN gamma. Further, the effect of IL-4 on glioblastoma proliferation is selective and independent of the mechanisms involved in regulating MHC antigen expression.
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PMID:Modulation of proliferation and antigen expression of a cloned human glioblastoma by interleukin-4 alone and in combination with tumor necrosis factor-alpha and/or interferon-gamma. 841 82


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