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

The expression of the IL-2R alpha-, beta-, and gamma-chains, CD25, CD122, and CD132, respectively, was investigated on fibroblast-like synoviocytes (FLS) and dermal fibroblasts (DF). Both protein and mRNA for CD122 and CD132 were observed but there was no evidence of CD25 expression. Quantification of the Ag binding sites for CD122 showed that FLS expressed 4 times more receptor molecules than DF. The functional capability of these receptors was confirmed by the production of monocyte chemoattractant protein-1 (MCP-1) in direct response to stimulation by IL-2, which could be inhibited by neutralizing anti-CD122 mAb. Both rheumatoid arthritis (RA) and osteoarthritis (OA) FLS and DF spontaneously produced MCP-1 in culture over a similar range of concentrations. However, RA and OA FLS produced significantly greater levels of MCP-1 following stimulation by IL-2 and IL-1 beta; RA FLS produced significantly more MCP-1 than OA FLS. Addition of exogenous IL-2 caused a slight, but significant, decrease in MCP-1 production by DF. The addition of neutralizing anti-CD122 mAb to FLS cultures partially, but significantly, reduced the IL-2-induced MCP-1 secretion, but did not effect either the spontaneous or IL-1 beta-induced secretion of MCP-1. Increased tyrosine phosphorylation was observed in FLS lysates following 30-min incubation with IL-2. In conclusion, in the inflamed synovium, as activated T cells migrate through the sublining and lining layer, T cell-derived IL-2 may activate FLS to secrete MCP-1, thus recruiting macrophages into the rheumatoid synovium and perpetuating inflammation.
 ...
PMID:Functional IL-2 receptor beta (CD122) and gamma (CD132) chains are expressed by fibroblast-like synoviocytes: activation by IL-2 stimulates monocyte chemoattractant protein-1 production. 1123 64

Distinct eosinophil populations have been characterized on the basis of discontinuous Percoll density gradients. In peripheral blood, normal individuals show a low number of normodense and hypodense eosinophils, contrasting with the high amount of hypodense cells in patients who have allergies. To characterize these two eosinophil populations, we analyzed membrane expression of several antigens and cytokine receptors in normodense and hypodense eosinophils from patients who have allergies and controls. Hypodense eosinophils expressed higher levels of CD122, CD69, and CD4 in both patients with allergies and control individuals when compared to normodense eosinophils. The expression of CD125, CD124, CD25, CD132, and CD23 were similar in both cell types.
 ...
PMID:Hypodense eosinophils: characterization of surface molecule expression. 1200 90

Like living Trypanosoma cruzi, its AGC10 membrane glycoprotein inhibits interleukin-2 (IL-2) secretion and membrane expression of CD25, CD122, and CD132 (the components of the high-affinity IL-2 receptor) by activated human lymphocytes. Since these molecules are required for effective lymphocyte division, we explored the molecular mechanism underlying these alterations. In the presence of AGC10 the cytoplasmic levels of IL-2 protein of CD4(+) and CD8(+) blood lymphocytes stimulated with phorbol myristate acetate (PMA) plus ionomycin were markedly reduced. AGC10 also decreased the intracellular levels of CD25, CD122, and CD132 in CD4(+) and CD8(+) cells stimulated with the T-cell mitogen phytohemagglutinin (PHA). These results indicated that the AGC10-induced alterations preceded IL-2 secretion and transport of IL-2 receptor components to the cell membrane. Supporting this view were the substantially diminished levels of IL-2, CD25, CD122, and CD132 mRNA found in AGC10-containing cultures of PHA-activated lymphocytes. These decreases were not due to increased mRNA instability. Thus, the rates of decay for each of these mRNA species were comparable in the presence or absence of AGC10, suggesting a mechanism involving transcription inhibition. AGC10 targeted an early lymphocyte activation event since inhibition of lymphoproliferation subsided when AGC10 was added to cultures at or after 20 h post-activation. AGC10 also caused large reductions in the mRNA levels of cyclin D2 and cdk4, both critical for progression through G1. These results show for the first time that AGC10-induced inhibition of lymphoproliferation entails curtailed biosynthesis of IL-2 and, IL-2 receptor molecules, and suggest that the effect involves inhibition of gene transcription.
 ...
PMID:The Trypanosoma cruzi membrane glycoprotein AGC10 inhibits human lymphocyte activation by a mechanism preceding translation of both, interleukin-2 and its high-affinity receptor subunits. 1246 77

Natural killer (NK) cells (CD56(+)/CD3(-)) in the circulation of cancer patients were reported to have low NK activity and undergo spontaneous apoptosis. A possible relationship between apoptosis and impaired NK activity was studied by Annexin V-binding and NK-cell assays performed with peripheral blood mononuclear cells of patients with head and neck cancer (HNC), breast cancer (BC) and normal controls (NC). Cells stained with Annexin V (Anx) and antibodies to CD56, CD3, CD95, CD25, CD122 or CD132 were examined by flow cytometry. NK activity was tested against K562 targets in 4-h (51)Cr-release assays. The ratio of CD56(dim)/CD56(bright) NK cells was significantly different in patients vs. controls (10 vs. 16; p<0.01). A significantly greater percentage of CD56(dim) NK cells bound Anx in HNC patients (27+/-17%, median +/- SD) or BC (46+/-18%) than in NC (15+/-18%, p<0.04 and p<0.0002, respectively). CD56(dim) NK cells were preferentially targeted for apoptosis. NK activity was significantly lower in patients with HNC and BC than in NC (p<0.009). An inverse correlation between NK activity and the percent of Anx(+)CD56(dim) NK cells was observed in cancer patients (p =0.002) but not in NC. In patients, circulating CD56(dim) NK cells were targeted for apoptosis, leading to low levels of NK activity.
 ...
PMID:Preferential apoptosis of CD56dim natural killer cell subset in patients with cancer. 1259 40

In this study we assessed, by flow cytometry, the effect of interleukin 2 (IL-2) on the oxidative burst of normodense eosinophils (Eos's) isolated from 15 patients with moderately severe extrinsic asthma and 17 controls. We found that IL-2 significantly induced peroxide (H2O2) production in normodense Eos's from patients with asthma on a time kinetics study. This rise was higher in patients with immunoglobulin E levels > 180 IU/mL versus normal immunoglobulin E values. The effect of IL-2 was partially blocked by using anti-Tac antibody. In contrast, IL-2 decreased H2O2 production in normodense Eos's from controls. Cell surface expression of CD25, CD122, CD132, and CD69 were also determined and no statistical differences were found between both groups. In conclusion, IL-2 is able to increase H2O2 production by normodense Eos's isolated from patients with asthma and it may contribute to bronchial epithelium damage and chronic inflammation.
 ...
PMID:Interleukin-2 induces peroxide production by primed normodense eosinophils of patients with asthma. 1263 75

Interleukin-15 (IL-15) is a cytokine that possesses interesting, potential therapeutic properties. However, based on several parameters including activation of neutrophils, it is also recognized as a proinflammatory cytokine. The mechanisms by which IL-15 activates human neutrophil functions are not fully understood. Although these cells express a functional IL-15 receptor (IL-15R) composed of IL-15Ralpha, IL-2/15Rbeta (CD122), and gamma(c) (CD132) subunits, the role of each receptor component has not been investigated in IL-15-induced human neutrophil responses. In the present study, fluorescein-activated cell sorter analysis revealed that the ability of IL-15 to enhance neutrophil phagocytosis is not a result of increased expression of IL-15Ralpha, CD122, or CD132 on the neutrophil cell surface. Pretreatment of neutrophils with specific antibodies to IL-15Ralpha, CD122, or CD132 was found to inhibit phagocytosis of opsonized-sheep red blood cells by nearly 40%, 21%, and 27%, respectively. As expected, pretreatment of neutrophils with anti-IL-2Ralpha (CD25) had no effect. Pretreatment of cells with the Syk inhibitor piceatannol was found to significantly inhibit the ability of IL-15 to enhance phagocytosis. In addition, IL-15 was found to induce tyrosine phosphorylation of Syk that was largely inhibited by pretreating cells with piceatannol. Moreover, we found that Syk kinase is physically associated with IL-15Ralpha. We conclude that IL-15R enhances neutrophil phagocytosis by a Syk-dependent mechanism and that the IL-15Ralpha chain plays a key role in mediating this response, at least by interacting with Syk kinase.
 ...
PMID:Interleukin-15 enhances human neutrophil phagocytosis by a Syk-dependent mechanism: importance of the IL-15Ralpha chain. 1512 70

Denileukin diftitox, a genetically engineered fusion protein combining the enzymatically active domains of diphtheria toxin and the full-length sequence for interleukin-2 (IL-2), efficiently targets lymphoma cells expressing the high-affinity IL-2 receptor (IL-2R) consisting of the alpha/p55/CD25, beta/p75/CD122, and gamma/p64/CD132 chains. In vitro studies demonstrated that the retinoid X receptor (RXR) retinoid, bexarotene, at biologically relevant concentrations of 10(-6) M to 10(-8) M, upregulated both the p55 and p75 subunits of the IL-2R and enhanced 5- to 10-fold the susceptibility of T-cell leukemia cells to denileukin diftitox. To determine whether this biomodulatory effect could be recapitulated in vivo, we treated 14 patients with relapsed or refractory cutaneous T-cell lymphoma with escalating doses of bexarotene (75 mg/day-300 mg/day) and denileukin diftitox (18 mcg/kg per day x 3 days every 21 days) in a phase 1 trial. Overall response was 67% (4 complete responses, 4 partial responses). Modulation of IL-2R expression was observed at or above a bexarotene dose of 150 mg/day. Four patients experienced grade 2 or 3 leukopenia, and 2 had grade 4 lymphopenia. Our results demonstrate that the combination of denileukin diftitox and bexarotene is well tolerated and that even low doses (150 mg/day) of bexarotene are capable of in vivo upregulation of CD25 expression on circulating leukemia cells.
 ...
PMID:A phase-1 trial of bexarotene and denileukin diftitox in patients with relapsed or refractory cutaneous T-cell lymphoma. 1581 59

Denileukin diftitox (ONTAK; Seragen Inc, San Diego, CA) is a fusion protein designed to direct the cytocidal action of diphtheria toxin to cells that overexpress the IL-2 receptor. The human IL-2 receptor exists in three isoforms: low (CD25), intermediate (CD122/CD132), and high (CD25/CD122/CD132) affinity. The high-affinity form of this receptor is expressed on activated T lymphocytes, activated B lymphocytes, and activated macrophages. A number of leukemias and lymphomas, including cutaneous T-cell lymphoma, chronic lymphocytic leukemia, and B-cell non-Hodgkin's lymphoma, express a component of the receptor. Ex vivo studies have shown that denileukin diftitox interacts with the high- and intermediate-affinity IL-2 receptor on the cell surface and undergoes internalization. Subsequent cleavage in the endosome releases the diphtheria toxin into the cytosol, which then inhibits cellular protein synthesis, resulting in rapid cell death. This article examines the clinical profile and potential benefits of denileukin diftitox in the treatment of cutaneous T-cell lymphoma and other hematologic disorders.
 ...
PMID:Clinical experience with denileukin diftitox (ONTAK). 1651 70

We demonstrate that humans have a phenotypically and functionally distinct subset of B lymphocytes that express the interleukin (IL)-2 receptor (IL-2R) alpha-chain, cluster of differentiation (CD) 25. We found that one-third of the circulating CD20+ B cells expressed CD25 and, using fluorescence-activated cell sorter (FACS) analysis, that these cells were significantly larger and more granulated than B cells not expressing CD25. The simultaneous expression of the other two subunits (CD122 and CD132) and the proliferative responses of cells expressing CD25 to IL-2 suggested that, in addition to CD25, functional IL-2 receptors were expressed on this cell population. CD25 expression on B cells was selectively up-regulated by Toll-like receptor 2 (TLR2), TLR4, and TLR9 ligands but not by a TLR3 ligand or Epstein-Barr virus (EBV) stimulation. Blockade of the nuclear factor (NF)-kappaB pathway completely abolished CD25 up-regulation by these B cells. Interestingly, CD25+ B cells expressed significantly higher levels of surface immunoglobulins but lacked the ability to secrete immunoglobulin (Ig), as compared with CD25- B cells. Furthermore, CD25+ B cells performed significantly better as antigen-presenting cells in allogeneic mixed lymphocyte reactions (MLR), which may be a result of their expression of high levels of the costimulatory molecules CD27 and CD80. Finally, blocking of CD25 on B cells led to an almost total abrogation of MLR. Our results indicate that CD25+ B cells have distinct phenotypic and functional properties, including the ability to contribute to antigen presentation, which is linked to their expression of CD25. Finally, the differential regulation of CD25 expression via selective TLR ligands suggests a role for CD25+ B cells in bridging innate and acquired immune responses.
 ...
PMID:Phenotypic and functional characterization of human CD25+ B cells. 1655 69

The contribution of tumor associated macrophage (TAM) to the induction of major histocompatibility complex (MHC) class I expression in vivo has not been reported precisely. In this study, we utilized Interleukin-2 (IL-2) cDNA-introduced B16 melanoma cells (B16/IL-2) and vehicle-alone control cells (B16/mock) to examine whether TAM could contribute to the induction of MHC class I on B16 cells in vivo. Interestingly, although B16/mock and B16/IL-2 did not express MHC class I in vitro, MHC class I was strongly expressed in vivo in B16/IL-2 in comparison to B16/mock. Although in vivo treatment of anti-NK1.1 antibody abolished MHC expression in B16/mock in vivo, the same treatment did not influence MHC expression in B16/IL-2. Interestingly, both anti-asialo GM1 and anti-CD11b treatment strongly decreased MHC expression in B16/IL-2. TAM expressed both asialo GM1 and CD11b antigen, and TAM recovered from B16/IL-2 produced interferon gamma (IFNgamma) 6 times more than that from B16/mock. In addition, TAM recovered from B16/IL-2 secreted 33.64 times more IFNgamma in response to in vitro administration of IL-2. Therefore, we checked whether or not IL-2 could influence the expression of IL-2 receptors. TAM recovered from IL-2 expressed middle affinity receptor of IL-2 (CD122 and CD132) while that from B16/mock expressed low affinity receptor (CD25 and CD132). Finally, we observed that B16 cells became apoptotic with IFNgamma treatment in vitro. These results suggested that IL-2 augmented activation of TAM would play the main role in induction of the MHC class I molecule through secretion of IFNgamma, and would contribute to the IFNgamma-mediated apoptosis induction in tumor cells.
 ...
PMID:Interleukin-2 augmented activation of tumor associated macrophage plays the main role in MHC class I in vivo induction in tumor cells that are MHC negative in vitro. 1659 36


<< Previous 1 2 3 4 5 Next >>