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Biomedical subjects

D Novick

Publications and source records attributed to D Novick.

At least 55 records · Page 3Linked to original sources
PubMed1996

Soluble IL-6 receptors (sIL-6R) in hematological patients receiving immunotherapy with IL-2/IFN-alpha or donor lymphocytes following bone marrow transplantation.

Soluble interleukin-6 receptor (sIL-6R) has previously been shown to potentiate the activity of interleukin-6 (IL-6) which may display antitumor activity. Therefore, we evaluated sIL-6R levels in the sera of 15 patients who received cytokine-mediated immunotherapy with (IL-2/IFN-alpha), and 15 patients who received cell-mediated immunotherapy post-BMT, in an attempt to reduce the relapse rate. sIL-6R levels were evaluated pre-, during and post-cytokine or cell-mediated immunotherapy, using IL-6R-specific monoclonal antibodies (McAb) and double-sandwich ELISA. In normal controls, sIL-6R levels were found to be 20 +/- 3 ng/ml. sIL-6R levels increased significantly during IL-2/IFN-alpha immunotherapy in comparison to pre- or post-immunotherapy levels (74 +/- 9 ng/ml vs 46 +/- 6 ng/ml, and 50 +/- 9 ng/ml, respectively) (n = 15) (P < 0.05). sIL-6R levels also significantly increased following donor lymphokine activated killer (LAK) cells, given in addition to IL-2, in comparison to base line levels (87 +/- 3 ng/ml vs 60 +/- 2 ng/ml) (n = 6) (P < 0.05). Increased levels of sIL-6R were observed in BMT patients treated with immunotherapy.

Adolescent↗
PubMed1995

Soluble and membrane-anchored forms of the human IFN-alpha/beta receptor.

The recently cloned ligand binding component of the type I human interferon-alpha/beta receptor (IFN-alpha/beta R) and its soluble analogue (p40) were characterized. p40 is a potent inhibitor of type I IFNs and antibodies directed against p40 completely block the activity of type I IFNs in human cells. These antibodies immunoprecipitate cellular 102-kDa (major) and 51-kDa (minor) forms of IFN-alpha/beta R. We find that the 51-kDa IFN-alpha/beta R. Two types of cDNA clones were isolated and sequenced, a 1.5-kb cDNA coding for the transmembrane 51-kDa IFN-alpha/beta R and a 4.5-kb cDNA coding for p40. In addition to ligand binding, IFN-alpha/beta R is directly involved in signaling, because it becomes phosphorylated at Tyr residues on ligand binding and it is physically associated with the cytoplasmic tyrosine kinase JAK1.

Amino Acid Sequence↗
PubMed1995

Soluble tumor necrosis factor receptors and soluble interleukin-6 receptor in fetal and maternal sera, coelomic and amniotic fluids in normal and pre-eclamptic pregnancies.

The aim of this study was (a) to measure soluble tumor necrosis factor receptors (sTNF-Rs) and soluble interleukin-6 receptor (sIL-6-R) in coelomic and amniotic fluids, cord and maternal sera in pregnancy and labor, (b) to examine whether the changes in concentrations of biologically active TNF and IL-6 are related to changes in their soluble receptors, and (c) to determine if levels of soluble receptors in pre-eclamptic disorders differ from normal pregnancies at delivery. Materials collected from 206 women during pregnancy and at delivery were analyzed for soluble receptors by enzyme-linked immunosorbent assay (ELISA). All receptors were present in higher concentrations in coelomic than in the corresponding amniotic fluid. Concentrations increased in amniotic fluid from first to second trimester. The level of sIL-6-R then remained unchanged to term, but there was a decrease in the sTNF-Rs which might account for the simultaneous appearance of bioactive TNF. Labor did not affect the concentration of any receptor in amniotic fluid. In maternal serum, sTNF-Rs increased with gestational age and labor in parallel with IL-6. The origin and physiological importance of these soluble receptors are still unknown. In pre-eclamptic disorders p55 sTNF-R was elevated in maternal serum before initiation of labor compared to normal pregnancy.

Adolescent↗
PubMed1995

Ligand-induced association of the type I interferon receptor components.

Two transmembrane polypeptides, IFNAR and IFN-alpha/Beta R, were previously identified as essential components of the type I interferon (IFN) receptor, but their interrelationship and role in ligand binding were not clear. To study these issues, we stably expressed and characterized the two polypeptides in host murine cells. In human cells, native IFN-alpha/beta R is a 102-kDa protein but upon reduction only a 51-kDa protein is detected. In host murine cells human IFN-alpha/beta R was expressed as a 51-kDa protein. Host cells expressing IFN-alpha/beta R bound IFN-alpha 2 with a high affinity (Kd of 3.6 nM), whereas cells expressing IFNAR exhibited no ligand binding. Upon coexpression of IFNAR and the 51-kDa IFN-alpha/beta R, the affinity for IFN-alpha 2 was increased 10-fold, approaching that of the native receptor. We show by cross-linking that both the cloned (51-kDa) and native (102-kDa) IFN-alpha/beta R bind IFN-alpha 2 to form an intermediate product, while IFNAR associates with this product to form a ternary complex. Hence, IFNAR and IFN-alpha/beta R are components of a common type I IFN receptor, cooperating in ligand binding. Ligand-induced association of IFNAR and IFN-alpha/beta R probably triggers transmembrane signaling.

3T3 Cells↗
PubMed1994

The human interferon alpha/beta receptor: characterization and molecular cloning.

We describe a universal ligand-binding receptor for human interferons alpha and interferon beta (type I IFNs). A soluble 40 kDa IFN-alpha/beta receptor (p40) that blocks the activity of type I IFNs was purified from urine and sequenced. Antibodies raised against p40 completely block the activity of several type I IFNs and immuno-precipitate both a cellular 102 kDa IFN-alpha/beta receptor and its cross-linked complexes with IFN-alpha 2. The receptor is a disulfide-linked dimer, consisting of 51 kDa subunits. We isolated and expressed a 1.5 kb cDNA, coding for the IFN-alpha/beta receptor. Its 331 amino acid sequence includes a leader and a transmembrane region, while its ectodomain corresponds to p40. IFN-alpha/beta receptor is physically associated with the cytoplasmic Tyr kinase JAK1, hence, in addition to ligand binding, it is directly involved in signal transduction.

3T3 Cells↗
PubMed1994

Serum soluble interleukin 6 (IL-6) receptor and IL-6/soluble IL-6 receptor complex in systemic juvenile rheumatoid arthritis.

By using a sandwich ELISA, soluble human IL-6 receptor (sIL-6 R) levels were measured in the sera of 20 healthy children and of 25 patients with systemic juvenile rheumatoid arthritis (JRA). In patients with systemic JRA, serum sIL-6 R levels (114.6 +/- 37.7 ng/ml) were significantly lower (P < 0.01) than those of healthy children (161.2 +/- 45.5 ng/ml). Serum sIL-6 R levels were negatively correlated (r = -0.610, P < 0.001) with serum IL-6 levels measured with the B9 cells. The serum IL-6/sIL-6 R complex was detected using an ELISA based on a monoclonal antibody to IL-6 for capture and on a monoclonal antibody to human sIL-6 R for detection. Healthy controls had little, if any, detectable serum IL-6/sIL-6 R complex (OD 0.024 +/- 0.027), while the majority of patients with systemic JRA presented measurable serum IL-6/sIL-6 R complex (OD 0.492 +/- 0.546). IL-6 levels estimated in the circulating IL-6/sIL-6 R complexes were in the range of nanograms per milliliter and approximately 20-fold higher than those measured by the B9 cells. Since serum C-reactive protein concentrations were much more correlated with serum levels of IL-6/sIL-6 R complexes (r = 0.713, r2 = 0.51, P < 0.0001) than with the serum IL-6 levels measured with the B9 cells (r = 0.435, r2 = 0.19, P = 0.05), the large quantities of serum IL-6 present in IL-6/sIL-6 R complexes appear to be biologically relevant in vivo, at least as far as the induction by IL-6 of acute phase protein production.

Adolescent↗
PubMed1994

Isolation and characterization of a soluble form of the LDL receptor, an interferon-induced antiviral protein.

Interferons (IFNs) act by inducing several intracellular antiviral proteins. We report here that IFNs also induce an extracellular soluble protein that inhibits vesicular stomatitis virus (VSV) infection. This protein accounts for 25%-50% of the total antiviral activity elicited by IFN. The antiviral protein was purified to homogeneity from culture supernatants of IFN-treated cells by several chromatographic steps, to give a single 28-kDa active polypeptide. Upon sequencing, this novel protein corresponded to the N-terminal ligand-binding domain of the human 160-kDa low-density lipoprotein receptor (LDLR). In addition, we find that IFN induces the cell surface LDLR and this phenomenon may explain previous reports on reduction of serum cholesterol in IFN-treated patients. Viruses produce soluble cytokine receptors that inhibit their respective cytokines, thereby assisting virus infection. It appears now that host cells employ similar molecules for the opposite role of controlling virus infections.

Amino Acid Sequence↗
PubMed1993

An antiviral soluble form of the LDL receptor induced by interferon.

Interferons, which induce several intracellular antiviral proteins, also induce an extracellular soluble protein that inhibits vesicular stomatitis virus (VSV) infection. This 28-kilodalton soluble protein was purified to homogeneity and identified by protein sequencing as the ligand-binding domain of the human 160-kilodalton low density lipoprotein receptor (LDLR). The existence of an antiviral soluble LDLR was confirmed by immunoaffinity chromatography with monoclonal antibody to LDLR. This soluble receptor mediates most of the interferon-triggered antiviral activity against VSV, apparently by interfering with virus assembly or budding, and not by inhibiting virus attachment to cells.

Amino Acid Sequence↗
PubMed1993

Interleukin-6 inhibits the proliferation of B-chronic lymphocytic leukemia cells that is induced by tumor necrosis factor-alpha or -beta.

Tumor necrosis factor (TNF-alpha) acts as a growth stimulatory factor on leukemic B lymphocytes from many patients with chronic lymphocytic leukemia (CLL). Because TNF induces production of interleukin-6 (IL-6), which has been shown to be a growth factor for myeloma and other transformed B cells, we examined the possibility that IL-6 mediates the growth-stimulatory effect of TNF on B-CLL cells. In fact, we found that IL-6 is an inhibitor of B-CLL growth. The addition of recombinant human IL-6 markedly decreased the TNF-induced B-CLL growth, and this decrease was even greater when soluble IL-6 receptor, known to act as IL-6 agonist, was added with recombinant IL-6. Conversely, neutralizing monoclonal antibodies to IL-6 and to the IL-6 receptor potentiated the growth stimulation of TNF on B-CLL cells, in line with the possibility that IL-6 functions as a negative feedback regulator of an autocrine TNF action on these B-leukemic cells. Evidence is presented that production of IL-6 by monocytes and B cells of CLL patients is low, suggesting that administration of IL-6 may be beneficial in CLL to reduce the eventual growth stimulation by TNF and, possibly, also the deficiency in platelets and Ig production in this disease.

Animals↗
PubMed1992

Soluble interferon-alpha receptor molecules are present in body fluids.

Soluble forms of the interferon-alpha receptor (sIFN-alpha R) were identified in human serum and urine by Western blotting with monoclonal antibodies (MAb) directed against IFN-alpha R, and by immunoprecipitation (Iptn) of a covalently cross-linked complex of IFN-alpha R and [125I]IFN-alpha with anti IFN-alpha MAb. Elevated levels of sIFN-alpha R were found in sera of hairy cell leukemia patients. The soluble receptor from serum migrated as a 55 kDa protein in SDS-PAGE, and, as expected, the cross-linked product migrated as a 75 kDa protein. The soluble receptor from urine was found to be a protein of mol. wt. 45 kDa and its cross-linked complex migrated as a 65 kDa protein. The calculated mol. wt. of the entire extracellular domain of the IFN-alpha R prior to post-translational modifications is 47,000. Since there are 12 potential glycosylation points in this extracellular domain, its actual mol. wt. may be as high as 70,000 Da. It is therefore concluded that sIFN-alpha R molecules, corresponding to truncated forms of the extracellular domain of the cell surface IFN-alpha R, are present in human serum and in normal human urine.

Animals↗
PubMed1992

Enhancement of interleukin 6 cytostatic effect on human breast carcinoma cells by soluble IL-6 receptor from urine and reversion by monoclonal antibody.

Interleukin 6 receptor soluble urinary protein (IL-6-R-SUP), a purified urinary protein binding IL-6 and identified as a truncated 50 kDa soluble form of the 80 kDa IL-6 cellular receptor, was tested for its biological activity. Addition of IL-6-R-SUP enhances the growth stimulation of mouse plasmacytoma T1165 by subliminal concentrations of human recombinant IL-6. Since this effect could be due to a lower affinity of human IL-6 for the mouse cell receptor, we tested the effect of IL-6-R-SUP on human cells. We show that the growth-inhibitory effect of IL-6 on breast carcinoma cells is enhanced by addition of IL-6-R-SUP to these human cells although they possess abundant IL-6 receptors. With IL-6-R-SUP, complete growth inhibition by IL-6 could be achieved and the cells became more sensitive to low levels of IL-6. These effects were prevented by a monoclonal antibody against IL-6-R-SUP which blocks IL-6 binding to cells. The naturally occurring IL-6-R-SUP may help to increase the growth-regulatory action of IL-6.

Animals↗
PubMed1992

Expression of active human interferon-beta in transgenic plants.

Tobacco plants were transformed with the human gene for interferon-beta (IFN-beta). Transformation was determined by the polymerase chain reaction (PCR), and expression was determined by Western blot analysis, by purifying the IFN from the transgenic plants, and by bioassays indicating its activity in human cells. Plants expressing IFN-beta were self-pollinated. IFN-beta-expressing progeny plants were selected and produced active IFN-beta, indicating stable transformation.

Base Sequence↗
PubMed1991

Differential signal transduction via T-cell receptor CD3 zeta 2, CD3 zeta-eta, and CD3 eta 2 isoforms.

The T-cell antigen receptor (TCR) consists of an antigen-binding heterodimer, termed Ti, which is noncovalently associated with the invariant CD3 subunits (gamma, delta, epsilon, zeta, and eta). The CD3 zeta and -eta subunits form either homodimeric or heterodimeric structures in turn associated with the other components of the TCR complex. This feature increases the structural complexity of TCRs by creating "isoforms." Both CD3 zeta and -eta are thought to play an important role in signal transduction triggered by antigen/major histocompatibility complex. To compare signaling functions of TCR isoforms, MA5.8, a CD3 zeta-eta- variant of the cytochrome c-specific, I-Ek-restricted T-cell hybridoma 2B4.11, was stably transfected with cDNAs encoding CD3 zeta and/or CD3 eta, and resulting clones were characterized. The findings indicate that signals inducing Ca2+ mobilization, phosphatidylinositol turnover, and interleukin 2 production are each transmitted by the above TCR isoforms. In contrast, tyrosine phosphorylation of the CD3 zeta subunit but not the CD3 eta subunit follows TCR stimulation. Given the general importance of tyrosine phosphorylation for receptor signaling, it is likely that this difference between TCR isoforms plays a regulatory role in T-lineage function by qualitatively or quantitatively altering signaling events.

Animals↗
PubMed1991

Monoclonal antibodies to the soluble human IL-6 receptor: affinity purification, ELISA, and inhibition of ligand binding.

Soluble IL-6 receptor (IL-6-R) purified to homogeneity from normal human urine was used for immunization of mice and rabbits. Spleen cells derived from a mouse showing a high binding titer to IL-6-R in an inverted solid phase radioimmunoassay (IsRIA) and in a Western blotting analysis were fused to mouse myeloma cells. The hybridomas were screened by the IsRIA, and 30 positive clones were isolated and characterized. They were suitable for affinity purification of the IL-6-R and for its detection by Western blot analysis, by ELISA and by sandwich type sRIA. Most of them inhibited the binding of labeled IL-6-R to IL-6 in a solid phase RIA.

Animals↗
PubMed1990

Purification of soluble cytokine receptors from normal human urine by ligand-affinity and immunoaffinity chromatography.

Affinity chromatography of crude human urinary proteins on either human recombinant interleukin-6 (rIL-6) or human recombinant interferon-gamma (rIFN-gamma) or anti IFN-gamma receptor (IFN-gamma-R) monoclonal antibodies (McAb) yielded the two respective soluble receptors in significant amounts. A single sequence of 30 amino acid residues was obtained by N-terminal microsequencing of the protein peak purified in tandem by affinity chromatography on an IL-6 column and reversed-phase high-performance liquid chromatography. This sequence was identical with the predicted N-terminal sequence of IL-6-R as previously reported. The purified IL-6-R retained its biological activity. It was used for the preparation of specific anti IL-6-R monoclonal antibodies. Analysis of the eluted proteins from both IFN-gamma and anti IFN-gamma-R columns by inhibition of solid-phase radioimmunoassay, enzyme-linked immunosorbent assay, sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting proved the existence of soluble IFN-gamma-R in normal urine. This finding together with the already known presence of soluble TNF receptors and a soluble IL-2 receptor found both in plasma and in urine indicates that release of soluble cytokine receptors into body fluids is a general phenomenon which occurs under normal physiological conditions.

Chromatography, Affinity↗
PubMed1990

Two tumor necrosis factor-binding proteins purified from human urine. Evidence for immunological cross-reactivity with cell surface tumor necrosis factor receptors.

Two proteins which specifically bind tumor necrosis factor (TNF) were isolated from human urine by ligand (TNF)-affinity purification, followed by reversed phase high performance liquid chromatography. The molecular weights of the two proteins, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were similar (about 30,000). Both proteins provided protection against the cytocidal effect of TNF in vitro and both bound TNF-alpha more effectively than TNF-beta. Antibodies raised against each of the proteins had an inhibitory effect on the binding of TNF to cells, suggesting that both proteins are structurally related to the TNF receptors. However, the two proteins differed in NH2-terminal amino acid sequences: Asp-Ser-Val-Cys-Pro- in one and Val-Ala-Phe-Thr-Pro- in the other. The NH2-terminal sequence of the former protein was invariable, while that of the latter was truncated to varying degrees. The two proteins were also immunologically distinct. The relative efficacy of anti-sera against the two proteins in inhibiting the binding of TNF to cells varied markedly from one line of cells to another. Evidence has been presented recently for the existence of two distinct molecular species of cell surface receptors for TNF and for differential expression of those two receptors by cells of different lines. The findings presented in this study are consistent with the notion that the urinary TNF-binding proteins constitute soluble forms of the two molecular species of the cell surface TNF receptors.

Binding, Competitive↗