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)

Synovial fluid mononuclear cells (SFMC) from patients with active rheumatoid arthritis characteristically respond poorly to mitogens. In this study, mitogenic antibodies reactive with the CD3(T3) antigen on human T lymphocytes were used to analyze the basis for the deficiency. OKT3-induced proliferation and release of interleukin 1 (IL-1) and interleukin 2 (IL-2) from SFMC were depressed in all patients. Purified IL-1 or recombinant IL-2 restored proliferative responses in SFMC and increased IL-2 receptor density. Exogenous IL-1 also enhanced IL-2 release. Fractionation of SFMC supernatants on phosphocellulose columns revealed the presence of IL-1 and a potent IL-1 inhibitor. The monocyte-derived IL-1 inhibitor blocked IL-1-dependent responses of normal peripheral blood lymphocytes to OKT3, but had no effect on IL-2-dependent events. These results suggest that IL-1 inhibitor(s) in SFMC impair(s) OKT3-induced mitogenesis by interfering with the effects of IL-1 on T lymphocytes. The net result is deficient IL-2 secretion, IL-2 receptor expression, and impaired cellular proliferation. This novel inhibitory circuit provides a rational explanation for the diminished function of synovial fluid T lymphocytes in rheumatoid arthritis patients.
J Clin Invest 1986 Sep
PMID:Basis for defective responses of rheumatoid arthritis synovial fluid lymphocytes to anti-CD3 (T3) antibodies. 309 36

Interferon (IFN)-alpha and IFN-beta ("type I" IFNs), but not IFN-gamma reduced phytohemagglutinin- or pokeweed mitogen (PWM)-induced proliferation in cultures of human mononuclear leukocytes. Proliferation induced by specific antigens (tuberculin PPD or tetanus toxoid) or by exogenous interleukin 2 (IL-2) was strongly inhibited by type I IFNs and, to a lesser extent, by IFN-gamma as well. Inhibition of proliferation in mitogen-stimulated cultures was not due to a reduced production of IL-2 or to an inhibition of IL-2 receptor expression. Type I IFNs inhibited immunoglobulin (Ig) production in PWM-stimulated unseparated mononuclear cells, whereas IFN-gamma enhanced Ig production in such cultures. In cultures of purified B cells type I IFNs caused a stimulation of Ig production and this B-cell differentiation factor (BCDF)-like activity of IFNs was synergistically enhanced in the presence of IL-2. IFN-gamma produced less BCDF-like activity than type I IFNs. These results show that in some instances type I IFNs can be more potent in affecting functions of cells of the immune system than IFN-gamma.
Cell Immunol 1986 Sep
PMID:Modulation of lymphocyte proliferation and immunoglobulin synthesis by interferon-gamma and "type I" interferons. 309 92

MRL/MP-lpr/lpr (MRL/l) mice spontaneously develop an age-related autoimmune disease concomitant with interleukin-2 (IL-2) defects. Induction of IL-2 receptor (IL-2R), IL-2 production and subsequent de novo DNA synthesis in MRL/l mice by the tumour-promoting phorbol ester 12-o-tetradecanoyl phorbol 13-acetate (TPA) and calcium ionophore (A23187) were examined. These two compounds given together induced significant IL-2R expression, IL-2 production, and de novo DNA synthesis of spleen cells from this murine strain, as did concanavalin A (Con A) plus TPA. TPA and A23187 may bypass the early steps of activation by mitogens in murine lymphocytes. However, even though these IL-2 defects could be overcome to some extent, the response of MRL/l mice to these stimuli was considerably lower than the enhanced IL-2R expression and IL-2 production of MRL/MP-+/+(MRL/n) control mice. These results suggested that the failure to respond to mitogens in these mice may be due, at least in part, to failure of receptor signal transduction, and to defects of molecular and biochemical reactions following signal transduction.
Immunology 1986 Sep
PMID:Synergistic induction by calcium ionophore and phorbol ester of interleukin-2 (IL-2) receptor expression, IL-2 production, and proliferation in autoimmune MRL/MP-lpr mice. 309 71

Isolated and combined effects of the calcium ionophore A23187 and of the protein kinase C activator phorbol myristate acetate (PMA) on T cell activation parameters were analysed on unprimed Balb/c lymph node T lymphocytes (LNL). High doses of PMA were mitogenic for resting T cells, but non-mitogenic doses of PMA induced T cell proliferation in combination with A23187, which was non-mitogenic by itself. Mitogenesis induced by a combination of A23187 and PMA (A23187/PMA) showed the following characteristics: it was not abolished after extensive depletion of accessory cells; purified L3T4+, but not Lyt2+ T cells responded in the absence of accessory cells; mitogenesis was completely blocked by a mixture of two monoclonal antibodies directed to the murine interleukin 2 (IL-2) receptor (7D4/3C7mAbs); cyclosporin A, dibutyril cyclic AMP, and T cell K+ channel blockers quinine and verapamil all blocked mitogenesis. A marked synergism between A23187 and PMA was noted in induction of T cell enlargement, IL-2 release, and induction of IL-2 responsiveness. No synergism was noted in IL-2 receptor expression, A23187 and PMA being able to induce IL-2 receptors alone. Calcium ionophore induced IL-2 receptor expression, but failed to induce IL-2 release and IL-2 responsiveness. Addition of A23187/PMA to the IL-2-dependent CTL-L clone did not result in cell proliferation. Addition of A23187/PMA to Con A-activated T cell blasts leads to a vigorous proliferative response. This response is blocked by 7D4/3C7 mAbs, indicating a role for endogenously produced IL-2 in this case. The results indicate that T cell mitogenesis by A23187/PMA is IL-2-dependent, and suggest a critical role for protein kinase C in IL-2 release and induction of IL-2 responsiveness. In addition, the data suggest distinct, but co-operative pathways of IL-2 receptor induction, controlled by elevated Ca2+ alone and by protein kinase C. Subsequent intracellular events of T cell activation by A23187/PMA may be quite similar to those triggered by Con A, since both kinds of stimulation are blocked by agents such as cyclosporin A, dbcAMP and K+ channel blockers.
Clin Exp Immunol 1986 Sep
PMID:Analysis of isolated and combined effects of calcium ionophore and phorbol ester on T lymphocyte activation. 309 19

Activated T cells express at least two distinct affinity classes of interleukin-2 (IL-2) receptors. The number of low-affinity receptors per cell is normally 10-30 times greater than that of the high-affinity receptors, and the difference in the dissociation constant between the two classes of receptors is in the order of 1,000-fold. In this report normal human T cells are used in a cellular system in which the number of low-affinity receptors can be manipulated. It is demonstrated that a cell population could be achieved with such low levels of low-affinity IL-2 receptors that almost half of the surface pool of anti-IL-2 receptor antibody (anti-Tac) binding sites represented high-affinity receptors. By using this cellular system it was possible to show that anti-Tac recognizes both receptor classes with similar affinity and that IL-2 inhibits Tac binding to both receptor classes in a competitive fashion. Tac antigens were purified from surface 125I-labeled cells expressing high levels of high-affinity IL-2 receptors, but low levels of the low-affinity receptor class, and this preparation was compared with another pool of Tac antigens obtained from cells expressing the normal 10- to 20-fold excess of low-affinity IL-2 binding sites over high-affinity IL-2 receptors. Biochemical characterization by peptide mapping by limited proteolysis and two-dimensional gel analysis revealed that these distinct preparations of Tac antigens were indistinguishable.(ABSTRACT TRUNCATED AT 250 WORDS)
EMBO J 1986 Sep
PMID:Structural analysis of high- versus low-affinity interleukin-2 receptors by means of selective expression of distinct receptor classes. 309 17

Interleukin 2(IL-2), a lymphokine that is produced by helper T cells, plays a key role in the proliferation of T lymphocytes by interacting with a specific cell surface receptor. Recent studies demonstrated that the IL-2 receptor exists in two forms having different affinities to the ligand and the growth signal seems to be delivered by IL-2 bound to the high affinity, but not the low affinity, receptor. In man, both forms of the IL-2 receptor can be recognized by a monoclonal antibody, anti-Tac. Using this antibody, a cDNA that encodes Tac antigen has been cloned from ATL-derived T cell line. Transfection of the cloned cDNA into mammalian non-T cells, however, resulted in the expression of only a non-functional, low affinity IL-2 receptor. This observation raised a question whether or not the cloned cDNA for Tac antigen actually encodes the functional, high affinity IL-2 receptor. In order to clarify this problem, Tac antigen cDNA was obtained from human PBL cDNA library. This cDNA was connected to RSV-LTR and was transfected into mouse thymoma derived T-cell line EL4, and L929 fibroblast. Then transformants that constitutively express Tac antigen were established. IL-2 binding assay demonstrated that EL4 transformants expressed high affinity as well as low affinity human IL-2 receptor. In contrast, L929 transformants expressed only a low affinity receptor. The growth of the EL4 transformants harboring the high affinity human IL-2 receptor was inhibited by virtue of the specific interaction of the receptor with human, but not mouse, recombinant IL-2. These results demonstrate: the cloned cDNA dose encode a functional IL-2 receptor, the affinity of the IL-2 receptor is variably modified by post-translational events and 3. IL-2/receptor interaction leads to the reversal of the cell growth in EL4 cells. The reconstitution system described here will be of great use in elucidating the mechanism of T cell growth.
Hokkaido Igaku Zasshi 1986 Sep
PMID:[Expression of functional human interleukin 2 receptor in mouse cells by using gene transfection]. 309 55

A bovine papilloma virus-derived vector was used to direct the high level expression in mouse C127 cells of three different cDNAs encoding the human interleukin-2 receptor. These were: the previously described cDNA clone isolated from the T-cell lymphoma, HUT-102; a cDNA clone isolated from mitogen-activated, normal peripheral blood T cells; and an altered version of the HUT-102 receptor in which Ser247, believed to be the site of protein kinase C-mediated phosphorylation, has been changed to an Ala residue. Fluorescence-activated cell-sorting using a monoclonal antibody directed against the human IL-2 receptor was used to derive stable lines of C127 cells expressing from 2-6 X 10(6) IL-2 binding sites per cell. However, all of these receptors bound IL-2 with low affinity.
Mol Immunol 1986 Sep
PMID:High level stable expression of human interleukin-2 receptors in mouse cells generates only low affinity interleukin-2 binding sites. 309 20

Phorbol ester phorbol myristate acetate (PMA) induces proliferation in nonmalignant human B cells and B cells from a patient with B prolymphocytic leukemia (B-PLL). Mitogen-free T cell-derived conditioned medium acts synergistically with PMA in inducing proliferation of B-PLL cells but does not enhance the PMA-stimulated outgrowth of nonmalignant B cells. Interleukin 2 (IL-2) has no effect on the outgrowth of B-PLL cells, and monoclonal antibodies against the IL-2 receptor do not influence the response to PMA and conditioned medium. Recombinant interferon-gamma (IFN-gamma), in contrast, is a potent enhancer of PMA-induced proliferation of B-PLL cells. With gel filtration techniques and with the use of anti-IFN-gamma antibodies, it is shown that IFN-gamma in the conditioned medium is responsible for the observed increase in B-PLL cell proliferation. Preincubation of B-PLL cells with IFN-gamma induces responsiveness to PMA, whereas IFN-gamma alone had no effect on these cells when pretreated with PMA. The combined data show that, in the presence of PMA, native and recombinant IFN-gamma are growth factors for B cells from a B-PLL patient and that IL-2 is not involved in this process.
Blood 1987 Sep
PMID:Induction of proliferation of B prolymphocytic leukemia cells by phorbol ester and native or recombinant interferon-gamma. 311 13

In vitro lymphocyte proliferative response to purified protein derivative of tuberculin (PPD) was investigated in patients with tuberculosis. Peripheral blood lymphocytes (PBL) from patients with advanced, refractory tuberculosis showed a significantly depressed response compared with the response of PBL from patients with newly diagnosed tuberculosis (P less than 0.01). A further characterization of this low responsiveness to PPD revealed that PBL from these advanced tuberculous patients failed to generate interleukin-2 (IL-2) in response to PPD stimulation. IL-2 receptor (Tac antigen) expression on the surface of T cells after PPD stimulation was also impaired, although to a lesser extent, in the patients with advanced, refractory tuberculosis. We attempted to overcome the depressed in vitro response observed in PBL from patients with advanced, refractory tuberculosis and found that the addition of exogenous, recombinant IL-2 returned the depressed PPD-induced PBL proliferation in these patients to the level of response observed in PBL from patients with newly diagnosed tuberculosis. The addition of recombinant IL-2 also had a restorative effect (up regulation) in vitro on the partly impaired PPD-induced IL-2 receptor expression by PBL from the patients with advanced, refractory tuberculosis. Our results suggest that recombinant IL-2 may offer a novel approach to the therapy of advanced, drug-resistant tuberculosis.
Infect Immun 1987 Sep
PMID:Recombinant human interleukin-2 reverses in vitro-deficient cell-mediated immune responses to tuberculin purified protein derivative by lymphocytes of tuberculous patients. 311 46

The murine interleukin 2 (IL-2) receptor is a 55- to 60-kDa glycoprotein (p58) that binds IL-2 at a high and low affinity. In this investigation, we have identified sublines of EL4 that vary in their capacity to express high affinity IL-2 receptors after transfection of the IL-2 receptor cDNA. These and other cell populations were used to determine whether unique membrane molecules were specifically associated with the high affinity IL-2 receptor. Irreversible chemical cross-linking of [125I]IL-2 to only high affinity IL-2 receptors resulted in detection of IL-2 cross-linked to p58 as a 70- to 75-kDa band and other complexes of 90 to 95 kDa, 115 kDa, 150 kDa, 170 to 190 kDa, and 245 kDa. Antibodies specific for p58 resulted in precipitation of each of these complexes. However, disruption of noncovalent interactions prior to immunoprecipitation resulted in an inability to detect the material at 90 to 95 kDa. Therefore, we conclude that this complex most likely represented IL-2 cross-linked to a 75- to 80-kDa subunit that was noncovalently associated with p58. The other complexes greater than 150 kDa may represent these subunits cross-linked to each other. The detection of all the cross-linked complexes larger than 75 kDa appeared to be directly related to formation of high affinity IL-2 receptors because IL-2 was cross-linked only to p58 for three cell lines that exclusively expressed low affinity IL-2 receptors. Thus, high affinity murine IL-2 receptors are comprised of at least one alpha (p58)- and beta (p75)-subunit. Our data also raise the possibility of a more complex subunit structure.
J Immunol 1987 Sep 15
PMID:The murine interleukin 2 receptor. Irreversible cross-linking of radiolabeled interleukin 2 to high affinity interleukin 2 receptors reveals a noncovalently associated subunit. 311 79


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