Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P14784 (IL-2 receptor)
 3,849 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to examine whether the unresponsiveness of MHC class I-negative subclones of the EL4 thymoma to CD3 cross-linking can be restored by transfection of class I genes into the H-2-negative cells. Cell activation experiments with selected MHC class I-negative subclones and H-2b- and H-2Ld-positive transfectants showed that these cells are equally capable of secreting interleukin 2 (IL-2) after exposure to the phorbol ester phorbol 12-myristate 13-acetate (PMA) and ionomycin. In contrast, only the parental H-2-positive EL4 cells are capable of responding to treatment with immobilized anti-CD3 antibody with IL-2 secretion and IL-2 receptor expression. Measurements of intracellular free Ca2+ (Ca2+i) following anti-CD3 antibody-induced cross-linking of parental EL4 cells and H-2-negative and H-2b gene-transfected subclones showed that the parental cells and two of the class I transfectants, one H-2-positive and one H-2-negative, responded with a slow rise in Ca2+i, whereas one H-2-positive transfected cell clone was completely refractory to CD3 cross-linking. Modulation experiments using parental EL4 cells, H-2-negative subclones and H-2-positive transfectants demonstrated that the CD3 and class I molecules of these different cells are modulated to the same extent after exposure to specific antibodies. The present findings thus indicate that the unresponsiveness of H-2-negative EL4 subclone cells to CD3 cross-linking is not functionally associated with a lack of class I surface expression.
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PMID:T-cell activation. III. Attempts to activate MHC class I-negative and class I-transfected EL4 T-lymphoma cells by immobilized anti-CD3 antibody. 214 10

The molecular mechanism of signal transduction through the interleukin 2 (IL-2) receptor remains an enigma. Glycosylphosphatidylinositol (GPI) lipids were investigated as one component of this process. IL-2 stimulated the rapid (30 sec) loss of greater than 50% of GPI in the IL-2-dependent T-cell line CTLL-2. Half-maximal GPI loss was detected at 40 pM IL-2, coincident with the EC50 (20 pM) for IL-2-induced proliferation of this cell line. This effect was specifically inhibited by antibodies that bind either IL-2 or the IL-2 receptor. The loss of GPI was mirrored by the accumulation of both polar inositolphosphoglycan (IPG) and diacylglycerol lipid fragments within cells. Increases in lipids were initially restricted to myristoyl diacylglycerol but were followed by the accumulation of myristoyl phosphatidic acid. These results are indicative of IL-2-dependent hydrolysis of GPI in T cells. The biological relevance of this hydrolysis was demonstrated by synergism of purified IPG with IL-2 in T-cell proliferation responses. The inclusion of IPG (0.1 microM) in determinations of IL-2-dependent CTLL-2 growth shifted the EC50 from 20 to 7 pM IL-2. IPG had no effect on either the number or affinity of IL-2 receptors; therefore, half-maximal CTLL-2 proliferation was obtained at less than 10% IL-2 receptor occupancy. These results demonstrate that GPI lipids are an important component of the biological response to IL-2.
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PMID:Regulation of interleukin 2-dependent growth responses by glycosylphosphatidylinositol molecules. 214 15

To elucidate the role of interleukin 2 (IL-2) activation in CD3- lymphocytes, we examined the ability of monoclonal antibody (MAb) TU27, developed against the IL-2 receptor (IL-2R) p75 protein (IL-2R beta), to block lymphocyte activation with exogenous IL-2, as well as its innate ability to activate lymphocytes as a result of its surface ligand interaction. The binding of the TU27 MAb and the results of 125I-IL-2 cross-linking experiments suggest that the IL-2R beta chain is expressed primarily on CD3-, CD56+ lymphocytes; although the protein was also detected in a small portion of CD3+ cells, its expression appeared to be donor dependent. In the present study, we found that TU27 totally blocked natural killer (NK) cell activation in a 4-h assay but had no effect on basal levels of NK activity. When treatment was extended to 24 to 72 h, the MAb was able to block the induction of both NK and lymphokine-activated killer (LAK) activity. Of interest was the observation that MAb treatment alone augmented NK activity and subsequent interferon gamma (IFN gamma) production in CD3- lymphocytes but did not activate LAK activity or induce cell growth. Collectively, these results indicate that TU27 not only reacts with p70-75 IL-2R beta but can abrogate IL-2 binding and subsequent activation events. In addition, some CD3- lymphocyte functions (e.g., NK activity and IFN gamma secretion) are directly induced by the binding of MAb to p70-75 through signals that only partially mimic IL-2.
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PMID:Regulation of CD3- lymphocyte function with an antibody against the IL-2 beta chain receptor: modulation of NK and LAK activity and production of IFN gamma. 215 85

Synergistic and cooperative effects in vitro of OKT3, interleukin 2 (IL-2), and tumor necrosis factor alpha (TNF) as stimuli in generating effectors with lymphokine-activated killer activity were studied. Activation of human peripheral blood mononuclear cells with OKT3 (10 ng/ml) for 48 h, followed by culture in low concentrations of IL-2 (10 units/ml) and TNF (250 units/ml) resulted in higher cell recovery (50- to 3300-fold) compared to the number of cells in the initial culture and enhanced lytic activity against both Raji and fresh lung tumor targets (mean 100-fold) by day 30 compared to those expanded with higher concentrations of IL-2 (100 units/ml) alone. Immunofluorescence analysis of peripheral blood mononuclear cells initiated with OKT3 and expanded with IL-2 plus TNF revealed a selective increase in CD8+ cells and a decrease in CD4+ by day 28; the opposite effect was observed when cells were incubated with 100 units/ml of IL-2 alone, resulting in a greater proportion of CD4+ cells. Almost all cells were CD3+. Studies of cytokine receptor expression indicated that OKT3 plus IL-2 plus TNF caused an earlier up-regulation of the IL-2 receptor beta chain (Tac) and higher TNF receptor expression by day 6 compared to 100 units/ml IL-2 alone. Significant TNF levels (greater than 17 units/ml) were measured in culture supernatants from peripheral blood mononuclear cells initiated with OKT3 alone. Collectively, our data demonstrate that induction of lymphokine-activated killer activity with OKT3, followed by culture in low concentrations of IL-2 plus TNF is an alternative to the use of high-dose IL-2 alone and suggest that this combination may provide potential advantages in long-term generation of cytolytic cells.
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PMID:Characterization of OKT3-initiated lymphokine-activated effectors expanded with interleukin 2 and tumor necrosis factor alpha. 216 Mar 21

Anti-Tac(Fv)-PE40 is a recombinant single-chain immunotoxin containing the heavy and light variable regions of the anti-Tac monoclonal antibody fused to a mutant form of Pseudomonas exotoxin (PE). Anti-Tac binds to the p55 subunit of the human interleukin 2 (IL-2) receptor, and anti-Tac(Fv)-PE40 kills human or monkey cell lines that contain either the intact IL-2 receptor or its p55 subunit alone. To assess the usefulness of anti-Tac(Fv)-PE40 in treatment of IL-2 receptor-positive leukemia, we tested peripheral blood mononuclear cells from six patients with adult T-cell leukemia. In each of the six patients, anti-Tac(Fv)-PE40 was extremely cytotoxic to the malignant cells. Metabolic activity and sensitivity of the fresh cells improved when a small amount of IL-2 (10 units per ml) was present during incubation. The toxin concentration necessary to inhibit protein synthesis by 50% after 16-hr incubation of cells with immunotoxin varied from 1.6 to 16 ng/ml (2.5-25 x 10(-11) M). In every case, binding was by means of the Tac antigen because anti-Tac(Fv)-PE40 cytotoxicity was prevented by adding excess anti-Tac antibody. Moreover, anti-Tac alone or an inactive mutant of anti-Tac(Fv)-PE40 without ADP-ribosylation activity had very little cytotoxic activity. Peripheral blood mononuclear cells from normal controls, from a patient with Tac-negative leukemia, and from adult T-cell leukemia patients without significant peripheral blood involvement were not sensitive to anti-Tac(Fv)-PE40. These results indicate that anti-Tac(Fv)-PE40 is a potent cytotoxin against adult T-cell leukemia cells in vitro and warrants clinical testing.
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PMID:The recombinant immunotoxin anti-Tac(Fv)-Pseudomonas exotoxin 40 is cytotoxic toward peripheral blood malignant cells from patients with adult T-cell leukemia. 223 41

A 76-year-old woman developed angiosarcoma 11 years after a radical mastectomy in the chronic lymphedema of the ipsilateral arm, referred to as Stewart-Treves syndrome. The patient was treated by intravenous and intralesional injection of recombinant interleukin 2 (rIL-2; TGP-3, Takeda Chemical Industries, LTD, Osaka). Intralesional injection was more effective than systemic administration. After a month, the lesion where the local injection was done showed little tumor cells with a dense infiltrate composed of lymphoid cells. It was observed that NK activity, LAK activity and IL-2 receptor positive T-cells in the peripheral blood increased during the administration of rIL-2. As the lesion was too large to be treated with rIL-2 alone, radiotherapy was performed. But the patient had no remarkably improvement and died 16 months later from the onset. Immunotherapy with rIL-2 can be useful for angiosarcoma and more effective regimen of rIL-2 is a important problem.
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PMID:[A case of Stewart-Treves syndrome--treatment with recombinant interleukin 2 and a review of Japanese literature]. 226 96

We studied the levels of membrane-bound and soluble-form interleukin 2 (IL-2) receptors in forty patients with rheumatoid arthritis. Levels of IL-2 receptors in the sera and synovial fluid of patients with rheumatoid arthritis were elevated when compared to values observed in normal sera and synovial fluid derived from the osteoarthritic joint. Simultaneous elevation of IL-2 receptor expression in blood and synovial fluid lymphoid cells was also detected, but no correlation was found between the two parameters nor between serum IL-2 receptor levels and the hemosedimentation rate. We conclude that measurement of serum concentrations of soluble IL-2 receptors should be used with caution as an index of disease activity, but may be useful when used in conjunction with other parameters in the management of patients with rheumatoid arthritis.
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PMID:Simultaneous evaluation of membrane bound and soluble interleukin 2 receptor expression in the blood and synovial fluid of patients with rheumatoid arthritis. 228 27

Human autologous peripheral blood lymphocytes (PBL) and lymphocytes infiltrating renal cell carcinoma (TIL) were cultured with medium containing 1000 IU/ml of human interleukin 2 (IL-2). A high cytotoxic activity against fresh autologous as well as cultured allogenic tumor cells was developed. By culturing these lymphocytes with OKT3 monoclonal antibody during the initial 2 days of long-term culture, in terms of T cell activation signal, IL-2-driven lymphocyte proliferation was remarkably accelerated with maintenance of appreciable level of cytotoxic activity. The same culture method also induced an increase in OKT3 and IL-2 receptor positive lymphocyte population in LAK cells and TIL. This method may enable us to gain more autologous TIL in vitro for adoptive immunotherapy of renal cell carcinoma than the usual culture method with IL-2 alone. Five patients with metastatic renal cell carcinoma were treated with adoptive immunotherapy with TIL, LAK and IL-2. One patient with pulmonary metastasis has had a minor response which has lasted for 3 months so far. We have not experienced any serious side effects during the treatment.
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PMID:[Study on adoptive immunotherapy with tumor-infiltrating lymphocytes (TIL) for renal cell carcinoma--amplification of IL-2-elicited TIL proliferation by OKT3-monoclonal antibody]. 230 7

High-affinity receptors for interleukin 2 (IL-2) are expressed on T cells following activation. These receptors are composed of both alpha and beta chains. Expression of alpha chains and, therefore, expression of high-affinity receptors are critically regulated at the level of transcription initiation. We have further dissected the regulatory elements involved in controlling transcription of the IL-2 receptor alpha-chain (IL-2R alpha) gene. The IL-2R alpha promoter contains a kappa B site and binding sites for additional nuclear factors within a 50-base-pair region (positions -290 to -240 relative to the major transcription start site). These include one upstream of the kappa B site and one similar to the c-fos serum response element (SRE), which is downstream of the kappa B site. Mutation of the kappa B site decreases IL-2R alpha promoter activity in MT-2 cells (a T-cell line that has been transformed with human T-cell lymphotropic virus type I), but not in Jurkat cells (a T-cell leukemia line) that have been activated by phorbol 12-myristate 13-acetate (PMA). In contrast, mutation of a region upstream of the kappa B site decreases activity in PMA-induced Jurkat cells but increases activity in MT-2 cells. Mutation of the SRE-like site decreases activity in both cell types but the effect in PMA-induced Jurkat is more pronounced. Thus, these distinct cis-acting elements play different physiological roles in IL-2R alpha gene activation in MT-2 cells and PMA-induced Jurkat T cells. These studies provide direct evidence for a functionally significant SRE-like sequence in a gene other than c-fos and the actin genes and identify other elements that are critical for IL-2R alpha gene expression.
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PMID:The same target sequences are differentially important for activation of the interleukin 2 receptor alpha-chain gene in two distinct T-cell lines. 230 42

Inhibition by anti-HLA Class I monoclonal antibody (mAb) Q6/64 of phytohemagglutinin (PHA)-P-induced peripheral blood mononuclear cell (PMBC) proliferation is associated with a reduction of Tac expression and interleukin 2 (IL-2) secretion. To analyze the mechanism(s) underlying the latter phenomena, the Tac gene and IL-2 gene transcription was analyzed by a nuclear transcription assay. No synthesis of Tac and IL-2 mRNA was detected in PBMC stimulated with PHA-P in the presence of mAb Q6/64. In conjunction with our recently published data, these results indicate that the blocking by anti-HLA Class I mAb of PHA-P-induced PBMC proliferation reflects an inhibitory effect within the signal transduction pathway leading to transcriptional activation of IL-2 and IL-2 receptor genes.
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PMID:Inhibition by anti-HLA class I mAb of IL-2 and IL-2 receptor synthesis in lymphocytes stimulated with PHA-P. 231 Nov 26


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