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)

Tumor cells from 5 human B cell non-Hodgkin's lymphoma (B-NHL) patients were investigated for proliferative activity and idiotypic (Id+) immunoglobulin (Ig) secretion in serum-free medium without deliberate addition of B cell growth or differentiation factors (BCDF). These data were compared with cell surface marker expression, notably of activation antigens such as 4F2 and interleukin-2 (IL-2) receptor. Cells from all patients became 4F2 positive at the end of the 6-day culture period. Freshly drawn cells from 3 out of 5 patients expressed the IL-2 receptor (CD25; Tac antigen) or acquired this marker during culture in vitro and secreted relatively high levels of Id+ Ig in vitro. This correlated with elevated serum Id levels (greater than or equal to 0.5 micrograms/ml in vitro versus greater than or equal to 20 micrograms/ml in vivo). In the 2 CD25 (Tac)- B-NHL patients serum Id levels were below the detection limit and the amount of Id+ Ig secreted in vitro did not surpass 50 ng/ml. Only the B-NHL cells from a single patient were initially CD25 (Tac) positive and only these cells proliferated in serum-free culture. To test whether IL-2 receptor expression in the 3 CD25 (Tac)+ patients was functional, recombinant IL-2 (rIL-2) either alone or in conjunction with BCDF and recombinant IL-4 (rIL-4) was added to the cultures. In 2 out of 3 CD25 (Tac)+ patients rIL-2 was capable of enhancing proliferation or Ig secretion. In addition rIL-2 was found to enhance BCDF-mediated but not rIL-4 mediated responses. The third CD25 (Tac)+ B-NHL population was resistant to any of these lymphokines. Thus, this serum-free culture system may accurately reflect patient serum Id levels. IL-2 appears to regulate not only the in vitro but also the in vivo Ig secretion by neoplastic B cells.
 ...
PMID:Idiotypic immunoglobulin secretion by human B cell non-Hodgkin's lymphomas is related to the expression of the interleukin-2 receptor. 312 22

Cell sorter-purified small splenic L3T4+ cells from B6 mice were clonally expanded under limiting dilution (LD) conditions by coculture for 4-6 days with irradiated allogeneic stimulator cells in culture medium supplemented with various growth factor preparations. Proliferating L3T4+ cell clones were detected by [3H]thymidine uptake; interleukin 2 (IL-2) production of restimulated L3T4+ cell clones was measured in a sensitive colorimetric assay. IL-3 (but not IL-1 or IL-4) supported clonal expansion in vitro of many L3T4+ cell clones produced IL-2. The data were consistent with the hypothesis that only a single titrated precursor cell was limiting in the system. In the response to class II (bm12) H-2 alloantigen, 1 in 40-200 L3T4+ cells was induced to clonal growth; in the response to class I (bm1) H-2 alloantigen, a tenfold lower frequency (1 in 600-800) of inducible L3T4+ B6 cells was measured. A fraction of the generated L3T4+ cell clones showed IL-2-independent growth: anti-IL-2 receptor monoclonal antibodies (MoAb) (7D4 and PC61.5) blocked the proliferation of about 80% of the IL-2-producing L3T4+ cell clones, while about 20% of these clones seemed resistant to inhibition of proliferation by these MoAb. We have thus defined an LD system with high cloning efficiency for L3T4+ cells that does not depend on exogenous IL-2 supplements.
 ...
PMID:Limiting dilution analysis of the response of murine L3T4+ spleen cells to alloantigen. 312 76

Supernatants from phorbol myristate acetate (PMA)-stimulated EL4.IL2 cells (EL4.PMA), but not recombinant IL-2 (rIL-2), induced the production of cytotoxic T lymphocytes (CTL) in low density murine spleen cell cultures. CTL induction in these cultures was completely abrogated by treatment with anti-Thy-1 or anti-Lyt-2 antibody plus complement but not by anti-L3T4 antibody plus complement. Fractionation of EL4.PMA on a Sephadex G-150 column demonstrated that the CTL-inducing activity in EL4.PMA eluted with an apparent molecular weight of about 44,000 and was partially separated from IL-2. This 44,000 MW material was shown to contain insignificant amounts of PMA. Following a 3-day culture period with the partially purified factor, C57BL/6J thymocytes could proliferate and differentiate into cytotoxic cells in response to rIL-2, whereas there was no proliferation or generation of cytotoxic cells when the thymocytes were cultured in rIL-2 alone. The number of IL-2 receptor-positive cells in C57BL/6J thymocytes also increased from 1.1% to 22.8% after 3 days of culture in the partially purified factor. Recombinant IL-4 (BSF-1) and IL-5 (TRF), when used alone or in combination with rIL-2, were unable to induce a cytotoxic response under similar culture conditions. These findings are consistent with the interpretation that EL4.PMA contains a novel lymphokine that directly, or indirectly, induces the expression of IL-2 receptors on resting CTL precursors without intentional stimulation by specific antigen. In the presence of IL-2, these precursors may then differentiate into effector CTL.
 ...
PMID:Antigen-independent activation of cytotoxic T cells by lymphokines. 313 7

The inhibitory effects of CsA in cell-mediated immunity are well known. There is controversy about whether CsA directly inhibits the function of accessory cells as well as T lymphocytes. We have used northern blotting to compare the effects of CsA on several human monocyte and T cell mRNAs, and we have performed "CsA-pulsing" experiments to separately evaluate the effect of the drug on accessory and T cells during lymphocyte mitogenesis. CsA blocked the induction of several lymphokine mRNAs in stimulated T cells including IL-2, IFN-gamma, and IL-4. CsF, an analog that is ten times less active than CsA as an immunosuppressant, was some ten times less active in inhibiting lymphokine gene expression in culture. CsA and CsF had little effect on the mRNA for the 55 KD low-affinity IL-2 receptor, but there was decreased expression of the TAC antigen. Exogenous IL-2 reversed the CsA-mediated suppression of cell proliferation and TAC expression. This indicates that the primary block with cyclosporines is at the level of lymphokines rather than lymphokine receptors. CsA did not reduce the levels of several monocyte mRNAs, however. These included c-myc and Il-1 alpha/beta mRNAs, induced by PMA plus Con A, as well as HLA-DR alpha and gamma-Ip10 mRNAs in monocytes treated with IFN-gamma. When monocytes were pulsed with CsA, there was no reduction in their subsequent accessory function for anti-CD3 and lectin responses. T lymphoblasts pulsed with CsA, however, did not proliferate or release growth factor. Likewise in the primary MLR between dendritic cells and T cells, dendritic cells were not impaired following pulsing with CsA, whereas treated T cells made 70% less IL-2. The primary site of action of CsA therefore seems to be the production of lymphokines by T lymphocytes.
 ...
PMID:Evidence that cyclosporine inhibits cell-mediated immunity primarily at the level of the T lymphocyte rather than the accessory cell. 313 67

In the model system used here, cross-linking of T-cell receptor structures (TCR) by antigen-presenting cells (APCs) is substituted by the use of anti-F23.1 anti-T-cell receptor monoclonal antibody immobilized on Sepharose beads. We show that CR cross-linking of resting murine CD8+ T cells seeded at low cell densities is insufficient to induce responsiveness to the growth-promoting effect of interleukin-2 (IL-2), i.e. fails to induce expression of functional IL-2 receptors. The macrophage cell-line product, IL-2 receptor-inducing factor (RIF), but not IL-1, IL-3, IL-4 and interferon-gamma (IFN-gamma) functions efficiently as a co-stimulator. Once activated, growth of CD8+ T cells is driven entirely by IL-2. We conclude that two restriction points control the activation of resting CD8+ T cells. While cross-linking of TCR is essential as the first step, RIF is required as the competence factor to induce IL-2 responsiveness. We consider the possibility that the ability of APCs to produce RIF determines the immunogenicity of APCs towards antigen-reactive resting CD8+ T cells.
 ...
PMID:Two distinct signals regulate induction of IL-2 responsiveness in CD8+ murine T cells. 313 55

Recently, we reported the isolation of a cDNA clone that encodes a polypeptide which has B cell and T cell growth factor activities. The amino acid sequence of this polypeptide deduced from the nucleotide sequence of the cDNA clone showed significant homology with mouse B cell stimulating factor-1. Because of its multiple biologic activities, it was designated interleukin 4 (IL-4). Here we describe the effects of supernatants of Cos-7 mouse cells transfected with the IL-4 coding cDNA clone in a mammalian expression vector, on human thymocyte T cells and T cell clones. The T cell growth-promoting effect of IL-4 on preactivated T cells was not inhibited by monoclonal antibodies against IL-2 or the IL-2 receptor, indicating that the IL-4 activity is independent from IL-2 or the IL-2 receptor. IL-4 induces a low proliferative response in thymocytes and peripheral blood lymphocytes, but the response was considerably enhanced by preactivation of the thymocytes or peripheral blood T cells. Both T4+ and T8+ antigen-specific proliferative and cytotoxic T cell clones and T3 natural killer clones proliferated in response to IL-4. But one of six T4+ and one of four T8+ T cell clones were consistently found to be unresponsive. The proliferative responses to IL-4 were always lower than those obtained with IL-2. Most of the T cell clones generally became unresponsive to IL-4 10 days after stimulation, but still responded well to IL-2. These results indicate that the responsiveness to IL-4 is relatively short lasting and is regulated by activation signals. Interestingly, IL-4 acted in synergy with IL-2 in promoting the growth of T cell clones. Our results establish that IL-4 can act as a T cell growth factor independently of IL-2.
 ...
PMID:Recombinant interleukin 4 promotes the growth of human T cells. 349 96

The IL-2 receptor (IL-2R) consists of three subunits, the IL-2R alpha, IL-2R beta, and IL-2R gamma chains, the last of which is also used in the receptors for IL-4, IL-7, IL-9, IL-13, and IL-15. The IL-2-induced proliferative signals emanate from the cytoplasmic domains of IL-2R beta and IL-2R gamma, but the nature and function of the signaling molecules that transmit these signals are not fully understood. Here we summarize our current understanding of the mechanisms by which IL-2R transmit signals by using multiple protein kinases. In fact, at least four protein tyrosine kinases (PTKs) are physically associated with IL-2R: p56lck (and its members), Syk PTK, and the Janus kinases, Jak1 and Jak3. cDNA expression studies revealed that the activation of these PTKs is critical for IL-2-induced proliferative signal transmission. Our findings indicate that a unique property of the IL-2R cytoplasmic domains is to recruit a variety of signaling molecules, which may suggest a mechanism by which these PTKs and other signaling molecules function in concert.
 ...
PMID:IL-2 signaling involves recruitment and activation of multiple protein tyrosine kinases by the IL-2 receptor. 748 66

The majority of patients with Dermatitis Herpetiformis (DH) have a gluten-sensitive enteropathy which may be triggered by a T cell-mediated immune response to gluten. Using a proliferative assay, the responses to gluten fraction III, recall antigens and mitogens of peripheral blood mononuclear cells (PBMC) and gut T cell lines (TCL) isolated from patients with Dermatitis Herpetiformis (DH) and normal controls were studied. In most cases, neither PBMC nor gut T cell lines (which were predominantly CD3+, CD4+, TCR alpha beta +) from either controls or patients proliferated in response to gluten fraction III alone. However, the addition of 10 U/ml IL-2 to PBMC cultures containing gluten fraction III resulted in a marked increase in proliferation in 9/19 DH patients and 7/11 controls compared to IL-2 alone. Furthermore, gluten-induced upregulation of IL-2 receptor (CD25) expression was demonstrated on PBMC from 4/4 patients with DH and 2/3 controls after 7 days' culture with antigen. A similar effect by exogenous IL-2, or the same concentration of IL-4, was observed in 8/11 (P = 0.02) and 5/6 respectively DH, and 3/4 normal gut T cell lines. No difference was observed in the response of DH and control PBMC to Tetanus toxin, Candida albicans and PPD; both normal and DH gut T cell lines were unresponsive to these antigens. However, the addition of IL-2 increased the response to Candida albicans by DH gut T cell lines. Moreover, the response of DH gut T cell lines to PHA (P < 0.001), Concanavalin A and anti-CD3 were markedly reduced compared to PBMC from the same patients. These findings suggest that gluten-specific T cells present in the blood and gut of normal and DH individuals are activated by but do not proliferate in response to specific antigen.
 ...
PMID:Lack of proliferative response by gluten-specific T cells in the blood and gut of patients with dermatitis herpetiformis. 749 50

Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3-dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin-like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL-13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS.
 ...
PMID:The insulin receptor substrate-1-related 4PS substrate but not the interleukin-2R gamma chain is involved in interleukin-13-mediated signal transduction. 749 80

The cellular and molecular regulation of IL-4 mRNA expression in human tonsillar T lymphocytes was examined to define the mechanisms responsible for biphasic IL-4 mRNA expression in this lymphoid organ. Tonsillar T cells expressed IL-4 mRNA in a biphasic manner with peaks at 8 and 24 h after PHA stimulation. De novo protein synthesis was not required for IL-4 mRNA expression because cycloheximide treatment of tonsillar MNC did not ablate the response. Nuclear runoff assays demonstrated transcription of the IL-4 gene at 8 and 24 h, which was not affected by addition of actinomycin D. Separation of T cells into naive (CD45RAhi/CD29lo) and primed (CD45RAlo/CD29hi) subpopulations revealed that although naive and primed T cells expressed IL-4 mRNA at 8 h, the 24-h peak of IL-4 mRNA expression was solely due to primed (CD45RAlo/CD29hi) Th cells. This effect was tissue specific and IL specific in that 1) primed peripheral blood T cells had only one peak of IL-4 mRNA expression at 8 h and 2) in primed tonsillar T cells, mRNA expression of IL-2, IL-6 and IL-2 receptor and c-myc was not delayed. Thus, IL-4 mRNA expression in the tonsil differs depending on the surface expression of different isoforms of the leukocyte common Ag. The tissue- and stimulus-specific regulation of IL-4 mRNA in different lymphoid tissues may play an important role in regional immunoregulation.
 ...
PMID:Tissue-specific regulation of IL-4 mRNA expression in human tonsil. 750 59


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>