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)

Depletion of intracellular glutathione (GSH) inhibits the lectin-induced activation response of human T lymphocytes. GSH-depleted lymphocytes undergo a partial activation response to lectins but fail to undergo blast transformation. Several lines of evidence indicate that the inhibition of lymphocyte activation in GSH-depleted lymphocytes involves relatively late activation events. Firstly, lectin stimulation induces significant 14C-AIB uptake, IL-2 production and expression of IL-2 receptor but a near complete inhibition of 3H-uridine and 3H-thymidine incorporation. Comparable levels of IL-2 production and IL-2 receptor expression are seen in GSH-depleted lymphocytes allowed to recover from GSH depletion during lectin stimulation. However, in the latter case, 3H-uridine and 3H-thymidine incorporation are normal, and activation is completely restored. Exogenous IL-2 cannot restore activation in GSH-depleted lymphocytes. Furthermore, lymphocytes remain highly susceptible to inhibition by GSH depletion even after 48 h of lectin stimulation which is sufficient to induce early activation events in the Go----G1 transition, such as IL-2 receptor expression and IL-2 production. Exogenous GSH partially restores intracellular GSH levels and completely restores lymphocyte activation in GSH-depleted lymphocytes. Despite comparable degrees of GSH depletion, DL-buthionine-SR-sulfoximine and 2-cyclohexene-1-one inhibit lymphocyte activation to different degrees. The inhibition by 2-cyclohexene-1-one is consistently greater than would be predicted based on glutathione depletion per se. We conclude that GSH-dependent processes are important in relatively late steps of the activation sequence characterized by nuclear events with relative sparing of essential early steps in activation, such as IL-2 receptor expression and IL-2 production. The approximate minimal intracellular GSH concentration necessary to sustain a normal activation response is 2 nmol per 10(7) lymphocytes.
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PMID:The role of glutathione in lymphocyte activation--II. Effects of buthionine sulfoximine and 2-cyclohexene-1-one on early and late activation events. 170 48

Cyclosporine has dramatically improved the success rates for all forms of organ transplantation. However, its use is complicated by the frequent occurrence of hypertension and reversible nephrotoxicity. The iatrogenic hypertension induced by cyclosporine resembles a low-renin, salt-sensitive form of essential hypertension, which is often controlled with salt restriction and therapies counteracting renal salt acquisition, e.g., diuretics and calcium channel blockers (CCBs). CCBs may also counteract the direct vasoconstrictive effects of cyclosporine, as well as the effects of other vasoconstrictors, such as endothelin or thromboxane, that may be stimulated by cyclosporine. Additionally, CCBs may potentiate the immunosuppression of cyclosporine, yet minimize nephrotoxicity. We demonstrated that the in vitro combination of verapamil and cyclosporine had an additive inhibitory effect on the activation and function of human peripheral blood mononuclear cells in several assays of the afferent and efferent limbs of immunologic responses. This additive immunosuppression was not likely to have been related to these drugs' effects on interleukin-2 (IL-2) circuitry, since no additive inhibition of IL-2 production or IL-2 responsiveness was found. There was some additive inhibition of IL-2 receptor expression at the higher concentrations of verapamil and cyclosporine that were tested. Although the combination of verapamil and cyclosporine additively inhibited mitogen-induced 45Ca uptake, the inhibitory effect of cyclosporine appears to be due to an inhibition of lymphocyte activation rather than direct inhibition of calcium flux through the slow calcium channel, suggesting that the two drugs do not have additive effects in depressing the transmembrane flux of calcium. More recently, we have demonstrated that the inactive enantiomer of verapamil, which does not block the slow calcium channel, has identical immunosuppressive capabilities as the active enantiomer. Thus, the antiproliferative effect of verapamil is probably slow-calcium-channel independent and may represent the ability of the drug to interfere with muscarinic, alpha 1-adrenergic, or even opiate receptors on lymphocytes or to block lymphocyte potassium channels. An even better possibility is that verapamil may diminish necessary precursor molecule uptake into lymphocytes, since both the inactive and active isomeric forms of verapamil are capable of diminishing thymidine, uridine, and leucine incorporation into stimulated lymphocytes--necessary for DNA, RNA, and protein synthesis, respectively. These in vitro observations may have clinical applicability, as early studies demonstrate reduced rejection rates of cyclosporine-treated transplant patients receiving CCBs. Consequently, CCBs are important medications to be considered for use in cyclosporine-treated organ transplant recipients.
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PMID:Therapeutic benefits of calcium channel blockers in cyclosporine-treated organ transplant recipients: blood pressure control and immunosuppression. 203 18

We report here experiments on the analysis of cellular signal transduction in a series of patients with chronic B cell disorders (B cell chronic lymphocytic leukemia [B-CLL] and prolymphocytic leukemia). We compared the response of the leukemic cells with primary external signals (interleukin 2 [IL-2] or B cell differentiation factors [BCDF or IL-6]) with their response to secondary inducers (the phorbol ester (12-O-tetradecanoylphorbol-13-acetate [TPA] or the calcium ionophore A23187) that circumvent the first part of the signal transduction pathway by directly activating the key enzyme protein kinase C. One BCDF was synthesized by mitogen-activated peripheral blood B lymphocytes; a second BCDF was constitutively produced by the human bladder carcinoma cell line T24. Changes in morphology, Tac (IL-2 receptor) expression, RNA synthesis measured by 3H-uridine uptake, and immunoglobulin production tested by enzyme-linked immunosorbent assay were used as parameters of successful signal transduction. TPA alone and TPA plus A23187 (synergistically) effectively initiated differentiation in all the leukemia cases. Neither IL-2 nor BCDF (singly or in combinations) caused equivalent responses. On the other hand, IL-2 and BCDF produced a substantial differentiation effect on normal B lymphocytes. Our data suggest that (a) B-CLL cells are able to respond to direct stimulation of the second messenger pathway (through protein kinase C) but not to the physiological stimuli IL-2 or BCDF; (b) the defect in signal transduction appears to be located upstream of protein kinase C (a possible candidate is a G protein); (c) malignant B cells may spontaneously or after treatment with inducers express the IL-2 receptor (Tac antigen) in the absence of a functional differentiating response to IL-2; and (d) signs of proliferation/differentiation in B-CLL samples after incubation with IL-2 or BCDF might be due to contamination of the cell populations with residual normal B cells.
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PMID:Analysis of signal transduction in B chronic lymphocytic leukemia cells. 312 49

Initiation of T-lymphocyte proliferation by mitogen or antigen involves a cascade of gene activation events. Thus, by the time mitogen-activated T cells have reached the G1/S interface, many genes that are transcriptionally silent in G0, like the c-myc, IL-2, IL-2 receptor (IL-2R) and transferrin receptor (TfR) genes, have been transcriptionally activated. To understand the role of the individual genes in the activation process, one must be able to interfere specifically with the expression or function of each particular gene product. In this way, by blocking the IL-2R with an antibody, it has been demonstrated that IL-2/IL-2R interaction is required to induce TfR expression in activated T cells. When the function or expression of intracellular proteins is to be blocked, however, the need to introduce antibodies into the cytoplasm of viable cells, although possible, is a limiting factor. We have taken another approach, namely the exogenous addition to bulk cell cultures of small antisense oligomers. Sequence-specific antisense oligodeoxyribonucleotides have been reported to inhibit intracellular viral replication without interfering with cellular protein synthesis. Similarly, rabbit globin mRNA translation in a cell-free system and in rabbit reticulocytes has been inhibited by oligomers complementary to the globin mRNA initiation codon region. Recently, a pentadecadeoxyribonucleotide complementary to the initiation codon and four downstream codons of human c-myc mRNA was reported to inhibit the proliferation of the human leukaemic cell line HL-60 specifically. We report here that the same c-myc complementary oligonucleotide inhibits mitogen-induced c-myc protein expression in human T lymphocytes and prevents S phase entry. Interestingly, c-myc antisense treatment did not inhibit G0 to G1 traversal as assessed by morphologic blast transformation, transcriptional activation of the IL-2R and TfR genes, or induction of 3H-uridine incorporation.
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PMID:A c-myc antisense oligodeoxynucleotide inhibits entry into S phase but not progress from G0 to G1. 330 22

Delta-9-tetrahydrocannabinol (THC), the major psychoactive component in marijuana, has been shown to suppress a variety of interleukin-2-(IL-2)-dependent cellular functions in both murine and human lymphocytes. These effects were examined in both human peripheral blood lymphocytes (hPBL) and the IL-2-dependent murine cytotoxic T-cell line CTLL-2. Interleukin-2-induced thymidine uptake and uridine uptake were suppressed in a dose related manner when cells were co-incubated for 48 h with 100 U rhIL-2/ml and 1-10 micrograms THC/ml. Interleukin-2-induced protein synthesis was also suppressed in a dose related manner over this THC concentration range, with the hPBL being more susceptible to the suppressive effect of THC than the CTLL-2 cells. Autoradiographic analysis of the synthesized proteins from hPBL cell lysates reveals a generalized suppression of all nascent proteins in THC-treated cultures. Human natural killer cell activity is only affected at the highest concentration tested (10 micrograms THC/ml) while lymphokine-(IL-2)-activated natural killer cell activity is affected throughout the range of 1-10 micrograms THC/ml. Together these results suggest that THC interferes with the IL-2:IL-2 receptor signaling cascade at one or possibly many points causing a decrease in IL-2-induced metabolic activity and cytolytic function.
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PMID:Delta-9-tetrahydrocannabinol treatment results in a suppression of interleukin-2-induced cellular activities in human and murine lymphocytes. 752 19

Time-varying magnetic fields (TVMF), especially those of extremely low frequency (below 250 Hz), have been reported to have profound effects on biological systems due to the induced currents since the biological systems consist of electrolyte solution. We have been interested in utilizing TVMF for cellular immunomodulations, and have shown that the TVMF could augment macrophage activation. In this study, the effect of TVMF on lymphocyte activation was studied. Murine spleen lymphocytes were isolated from DDY mice and incubated in the presence of Concanavalin A (ConA) for 72 h. The lymphocytes were exposed to TVMF for various durations, from 20 min to 2 h. The proliferation activities of lymphocytes were assayed by ELISA by use of 5-bromo-2'-deoxy-uridine Labeling and Detection Kit III (Roche Diagnostic Corp. Indianapolis, IN, USA). The IL1beta and IL2 concentrations in the culture medium were measured by ELISA assay. The IL2 receptor expression on the lymphocytes was evaluated by FACS analysis by use of FITC-conjugated monoclonal antibody. The proliferation activities were significantly enhanced by the TVMF for up to 40 min exposure from the initiation of ConA stimulation. The degree of augmentation effects, defined by the ratio of activation index of with and without TVMF, was varied from 1.1 to 2.7, and related to the lymphocyte responsiveness to the ConA. The less responsive cells showed more TVMF augmentation effects. The TVMF exposure after 40 min from ConA addition showed no effect, suggesting that the TVMF effects are most likely related to the Ca ion influx. The prolonged exposure of TVMF depressed the augmentation effects, which was caused by the depressed IL-2 receptor expression although both IL1-beta and IL-2 productions were not affected.
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PMID:Functional modulation of activated lymphocytes by time-varying magnetic fields. 1515 72

Previous studies have suggested that Vigconic VI-28, an anti-aging traditional Chinese medicine (TCM) formula containing Radix Ginseng and Cornu Cervi Pantotrichum, possesses immunological efficacy. This in vitro study further investigated the immunomodulatory effects of the hot water extracts of VI-28. The study included (1) colorimetric 5-bromo-2'-deoxy-uridine proliferation ELISA for estimating mitogenicity in human peripheral blood mononuclear cells (PBMC), (2) immunofluorescence staining for measuring the expression of IL-2 receptor alpha (CD25) on lymphocytes, (3) cytometric bead array (CBA) for quantifying cytokine liberation from PBMC, and (4) intracellular immunophenotyping for macrophage phagocytosis and hydrogen peroxide (H(2)O(2)) production from monocytes. The results demonstrated that VI-28 (1) could dose-dependently inhibited the proliferation of unstimulated and lipopolysaccharide-activated PBMC but enhanced the proliferation of phytohemagglutinin-activated PBMC at concentrations of <1 mg/mL, (2) significantly augmented the expression of CD25 on lymphocytes at concentrations of 0.4 mg/mL or above (p < 0.05), (3) dose dependently (0.1-1.0 mg/mL) activated macrophage phagocytosis and monocyte synthesis of H(2)O(2) and (4) significantly increased the production of cytokines IL-8, IL-10, IL-12 and IL-1beta at various concentrations of VI-28 (p < 0.05). The results suggest that VI-28 is a potential immunomodulator which probably acts through the activation of lymphocytes and monocytes.
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PMID:In vitro immunomodulatory activities of a newly concocted traditional Chinese medicine formula: VI-28. 1690 39