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)

Alterations in the expression of cell-surface receptors have been reported in HIV-infected cells for CD4, CD25 (IL-2 receptor), CD2, CD3 and CD8 and CD26. In the present study we provide evidence that CD21 is down-regulated in the human T-lymphoblastoid cell line MT2 after infection with HIV-1 and -2 isolates. The same effect was observed with ICAM-1 (CD54). CD21 expression was monitored by means of fluorescence intensity, its functional ability to bind to C3d and by quantitative measurement of CD21-antigen in supernatants and cell lysates using an immunoassay. In addition, the decrease of CD21 and ICAM-1-specific mRNA suggests a mechanism at a transcriptional level. Our data suggest that HIV might have a direct influence on the receptor expression.
 ...
PMID:Reduced CD21 (CR2) and CD54 (ICAM-1) expression in MT2 cells with HIV-1 or HIV-2 strains. 759 Sep 24

The risk of developing adult T-cell leukemia (ATL) associated with neonatal infection by human T-cell leukemia virus type I (HTLV-I) suggests that early events triggered by HTLV-I might be of crucial importance in initiating the multistep lymphoproliferative process leading several decades later to the development of leukemic disease. Thus, infection of thymocytes early in life might be directly correlated with the development of ATL. In the present study, we show that in vitro infection of mature (CD2+CD3+) or immature (CD2+CD3-) thymocytes resulted in the exogenous interleukin (IL)-2-dependent proliferation of HTLV-I-positive thymocytes, most of them displaying a CD2+CD3-CD4+ phenotype and expressing the CD25 molecule, the alpha chain of the IL-2 receptor. Furthermore, the CD80 and CD54 antigens, normally expressed by thymic stromal cells, were detected on these transformed thymocytes, indicating that HTLV-I infection may disturb the cooperation between thymocytes and their thymic environment. These HTLV-I-positive thymocytes were producing significant amounts of IL-6, which was found to be implicated in their proliferation and in the expression of CD25, as demonstrated by blocking experiments using a monoclonal antibody to IL-6. The present study suggests that immature thymocytes may provide an environment favorable to the unfolding of events leading to leukemia.
 ...
PMID:Human immature thymocytes as target cells of the leukemogenic activity of human T-cell leukemia virus type I. 763 51

We explored the role of a new cytokine, IL-2 receptor-inducing factor (IL-2RIF), in intestinal mucosal immunity and in the regulation of integrin beta 7 receptors on intestinal lymphocytes. Most SIEL (small intestine intraepithelial lymphocytes) were M290 (alpha M290 beta 7) positive, while only 10 to 15% of SIEL were R1-2 (alpha 4) positive. The expression of alpha 4 (R1-2) and beta 7 (M293) but not alpha M290 beta 7 integrin on SIEL was up-regulated by IL-2RIF. Incubating SIEL with IL-2RIF resulted in the up-regulation of CD45RB and down-regulation of CD44. About 50% of LPL (lamina propria lymphocytes) were alpha M290 beta 7 positive, while only 20% of LPL were alpha 4 positive. The expression of alpha M290 beta 7 integrin on LPL was down-regulated and alpha 4 and beta 7 integrin was up-regulated by IL-2RIF. Incubating LPL with IL-2RIF resulted in the up-regulation of CD44 and no significant change of CD11a, CD45, CD45RB, and ICAM-1. These results suggested that SIEL and LPL may play a different role in intestinal mucosal immunity and that IL-2RIF may play an important role in regulating the functions of integrins beta 7 on IEL and LPL.
 ...
PMID:Expression of beta 7 integrins and other cell adhesion molecules on mouse lymphocytes and their modulation by a new cytokine, IL-2 receptor-inducing factor. 763 47

Acute P. falciparum malaria is associated with a loss of antigen-responsiveness of peripheral T cells, depletion of T cells characterized by high surface expression of the adhesion molecule LFA-1, and increased plasma levels of the T-cell activation marker soluble IL-2 receptor (sIL-2R). In the present study we show that clinical episodes of P. falciparum malaria produced an increase in plasma levels of soluble ICAM-1 (sICAM-1) and ELAM-1 (sELAM-1). The increase was transient and subsided slowly (sICAM-1) or rapidly (sELAM-1) following drug cure. The increases in plasma sICAM-1 and sELAM-1 were significantly correlated, and were furthermore associated with a concomitant increase in plasma levels of sIL-2R. Finally, plasma levels of sICAM-1, but not sELAM-1, were inversely correlated to the fraction of peripheral T cells having high surface expression of LFA-1, the receptor for T-cell adhesion to ICAM-1. Taken together, these observations suggest that acute P. falciparum malaria is characterized by a state of endothelial inflammation associated with the adherence of activated T cells.
 ...
PMID:Increased plasma levels of soluble ICAM-1 and ELAM-1 (E-selectin) during acute Plasmodium falciparum malaria. 768 46

Two major populations of extrathymically differentiated T cells exist in the liver and intestine. Such T cells in the liver have TCR of intermediate intensity (i.e., intermediate TCR cells) and constitutively express IL-2 receptor beta-chain (IL-2R beta), whereas those in the intestine, especially intraepithelial lymphocytes, have TCR of bright intensity, consisting of a mixture of IL-2R beta+ and IL-2R beta-. All mature thymocytes and thymus-derived T cells seen in the peripheral immune organs are TCR-bright+ IL-2R beta- under resting conditions. When the expression pattern of adhesion molecules, including CD44, L-selectin, LFA-1 and ICAM-1, was compared among these T-cell populations, they displayed quite unique patterns of expression. All extrathymic T cells in the liver, intestine, and even other organs were CD44+ L-selectin-LFA-1++ICAM-1+, whereas thymocytes and thymus-derived T cells were CD44-L-selectin+LFA-1+ICAM-1-. This inverted expression of adhesion molecules between extrathymic T cells and thymus-derived T cells might be associated with their unique tissue-localization.
 ...
PMID:A similar expression pattern of adhesion molecules between intermediate TCR cells in the liver and intraepithelial lymphocytes in the intestine. 779 43

32 monoclonal antibodies reactive with human CD antigens were tested against tamarin peripheral blood lymphocytes, ConA blasts and lymphoblastoid B cell lines derived from tamarin cells. Reagents that cross-react with MHC class I and II, B cells (CD20, -21 and -23), monocytes (CD14) and NK cells (CD16, -56) have been identified. In addition monoclonals that cross-react with T cells (CD2, CD3), the CD4/CD8 subsets of T cells and the IL-2 receptor (CD25) are reported. A monoclonal against the beta chain of LFA-1 (CD18) cross-reacted strongly, but there was only a very poor cross-reaction with a monoclonal against the alpha chain of CD11a. Two monoclonals tested against ICAM-1(CD54) were negative.
 ...
PMID:Selection of monoclonal antibodies for the identification of lymphocyte surface antigens in the New World primate Saguinus oedipus oedipus (cotton top tamarin). 783 81

The biological significance of the signals triggered by the interaction of cell surface expressed LFA-1 and ICAM-1 has been investigated in Con A and immobilized anti-CD3 mAb stimulated cultures. When added at the beginning of activation in the presence of Con A, soluble anti-LFA-1 and anti-ICAM-1 mAbs could strongly inhibit cell proliferation. Such inhibitory effect was also exhibited in the proliferative response of thymocytes to immobilized anti-CD 3 mAb activation. However, the soluble anti-LFA-1 mAb was unable to inhibit the proliferation of primed thymocytes preactivated with Con A for 24 h or of IL-1 + IL-2 activated fresh thymocytes. Anti-LFA-1 mAb could profoundly inhibit Con A-induced thymocytes to produce IL-2 and IL-6 and to reduce IL-2 receptor expression. By contrast, anti-LFA-immobilized on plastic plates together with immobilized anti-CD 3 mAbs or CD 3 cross-linking with LFA-1 by secondary antibodies resulted in an enhanced activation signals for thymocytes to proliferate compared with that activated by anti-CD 3 alone. Thus, mAb to LFA-1 is a functional molecule for thymocyte activation, mediating signals contributed to very early phases of signal transduction through TCR/CD 3 pathway, and that LFA-1 might provide a costimulatory signal for expression of IL-2 R and IL-2 production.
 ...
PMID:[Functional roles of LFA-1 involved in signal transduction for thymocyte activation]. 787 72

Major adhesion routes between lymphoid cells involve the receptor/ligand pairs LFA-1/ICAM-1 and CD2/LFA-3, in addition to VLA or CD44 molecules. In this study we evaluated the role of these adhesion receptors in the proliferative response of lymphoid cells to interleukin-2 (IL-2). Blocking studies were performed with a panel of monoclonal antibodies (mAb) directed against these adhesion molecules. Selective inhibition of recombinant (r)IL-2-induced cell proliferation was observed with mAb directed against the alpha or beta subunit of LFA-1 or to its ligand ICAM-1. Interestingly, rIL-2-induced proliferation was also inhibited by NKI-L16, and anti-1 alpha antibody known to enhance cell-cell interaction. Resting lymphocytes were preferentially susceptible to the inhibition, particularly in an early phase of culture and when stimulated with a relatively low dose of rIL-2. By using mAb that specifically could block distinct rIL-2 activation pathways, LFA-1/ICAM-1 interaction was found to be required for p55 IL-2 receptor (IL-2R)-mediated interaction of rIL-2 with its high-affinity receptor, but not for p75 IL-2R-mediated responses. Furthermore, it was shown that the rIL-2 response of T lymphocytes, but not of natural killer cells, was dependent on LFA-1/ICAM-1 interaction. This suggests that LFA-1/ICAM-1 interaction is required for an optimal rIL-2 response of cells capable of IL-2 secretion. Our data provide evidence for the hypothesis that adhesion receptor-directed release of IL-2 may result in a locally high concentration of IL-2 that triggers high-affinity IL-2R signaling and up-regulates p55 IL-2R to enhance cytokine responsiveness.
 ...
PMID:Role of LFA-1/ICAM-1 in interleukin-2-stimulated lymphocyte proliferation. 790 74

Helicobacter pylori colonization of the human gastric mucosa causes a long-term, not self-limiting inflammation, suggesting that the microbe has properties to protect itself against the host immune defence system. Recently we were able to demonstrate that H. pylori suppresses the in vitro proliferative response of human peripheral blood mononuclear cells to antigens as well as to mitogens without affecting cell viability. The purpose of this study was to clarify which cell subsets of mononuclear cells are influenced by H. pylori. The use of monocytes which had been pretreated with a soluble cytoplasmic fraction of H. pylori (30 micrograms ml-1) led to a suppressed proliferation of T cells after PHA-activation. Activation of isolated T cells with PHA and PMA revealed that the proliferative response of lymphocytes could also be inhibited independently of monocytes. The anti-proliferative effect was associated with a reduction of IL-2 receptor (CD25) expression as well as an inhibition of blastogenesis. Furthermore, the spontaneous proliferation of EBV-transformed B cell lines was suppressed in a dose-dependent manner. FACS-analysis of HLA-DR, ICAM-1 and CD14 expression on the surface of monocytes revealed an influence of H. pylori on CD14 expression at a concentration of 30 micrograms ml-1, while the expression of HLA-DR and ICAM-1 was not affected at this concentration.
 ...
PMID:Suppression of human mononuclear cell response by Helicobacter pylori: effects on isolated monocytes and lymphocytes. 790 99

The present study was designed to quantify the level of the soluble form of ICAM-1 (sICAM-1) produced by mononuclear cells (MNC) of rheumatoid arthritis (RA) patients, and to correlate these levels with the disease activity and with the amounts of cytokines or rheumatoid factors (RF) produced by MNC. Unstimulated synovial fluid (SF) MNC produced higher amounts of sICAM-1 than peripheral blood (PB) MNC in RA patients (P < 0.01). sICAM-1 production by PHA-stimulated MNC was higher in RA SF MNC than RA or normal PB MNC (P < 0.01). The amounts of SICAM-1 produced correlated with the amounts of soluble IL-2 receptor produced (P < 0.02) but not with IL-1B or the Lansbury activity index in RA PB MNC. sICAM-1 correlated with the amounts of soluble CD23 and IL-4 produced by normal PB MNC (P < 0.01). The amounts of sICAM-1 correlated with IgG-RF (P < 0.02) and IgM-RF (P < 0.01) produced by unstimulated MNC obtained from the bone marrow (BM) of RA patients. ICAM-1 expression of T-lymphocyte subsets, B lymphocytes, and monocytes obtained from RA PB and RA BM assayed by two-color flow cytometry ranged from 0.1 to 6%, which was not appreciably different from that of normal controls. The monocyte fraction of RA PB MNC produced significantly higher amounts of sICAM-1 than lymphocyte fraction. These results suggest that sICAM-1 produced by MNC may be a marker of cell activation in T and B lymphocytes, in contrast to the transient increase of ICAM-1 expression.
 ...
PMID:Production of soluble ICAM-1 by mononuclear cells from patients with rheumatoid arthritis patients. 791 53


<< Previous 1 2 3 4 5 6 Next >>