Showing papers by "Charles A. Dinarello published in 1995"

A randomized, controlled trial of IL-10 in humans. Inhibition of inflammatory cytokine production and immune responses.

Abstract: In vitro, IL-10 inhibits T cell proliferation and LPS-induced monocyte production of IL-1, TNF-alpha, IL-6, and IL-8. We studied the safety and immunomodulatory effects of IL-10 administration in humans. Seventeen healthy volunteers received a single i.v. bolus injection of either human IL-10 (1, 10, or 25 micrograms/kg) or placebo. Routine safety parameters, lymphocyte phenotypes, T cell proliferative responses, and stimulus-induced cytokine production were assessed before and 3, 6, 24, and 48 h after injection. There were no adverse symptoms or signs after IL-10 administration. A transient neutrophilia and monocytosis that peaked at 6 h (45-160% above base line) was observed. However, lymphocyte counts fell by 25% 3 and 6 h after the injection (p < 0.01). In particular, lymphocytes expressing the T cell surface markers CD2, CD3, CD4, CD7, and CD8 were significantly decreased. Mitogen-induced T cell proliferation was suppressed by up to 50% (p < 0.01) in the two higher dose groups. Significant dose-dependent inhibition (65-95%) of TNF-alpha and IL-1 beta production from whole blood stimulated ex vivo with endotoxin occurred after each dose of IL-10. In contrast, there was no reduction in the production of their respective antagonists, TNF soluble receptor p55 or IL-1 receptor antagonist. We conclude that a single intravenous injection of IL-10 is safe in humans, has inhibitory effects on T cells, and suppresses production of the pro-inflammatory cytokines TNF-alpha and IL-1 beta.

Osmotic regulation of cytokine synthesis in vitro

Abstract: These studies were undertaken to investigate the therapeutic mechanism of saturated solutions of KI, used to treat infectious and inflammatory diseases. The addition of 12-50 mM KI to cultured human peripheral blood mononuclear cells resulted in 319-395 mosM final solute concentration and induced interleukin (IL)-8 synthesis. Maximal IL-8 production was seen when 40 mM salt was added (375 mosM) and was equal to IL-8 induced by endotoxin or IL-1 alpha. However, there was no induction of IL-1 alpha, IL-1 beta, or tumor necrosis factor to account for the synthesis of IL-8; the effect of KI was not due to contaminating endotoxins. Hyperosmolar NaCl also induced IL-8 and increased steady-state levels of IL-8 mRNA similar to those induced by IL-1 alpha. IL-8 gene expression was elevated for 96 hr in peripheral blood mononuclear cells incubated with hyperosmolar NaCl. In human THP-1 macrophagic cells, osmotic stimulation with KI, NaI, or NaCl also induced IL-8 production. IL-1 signal transduction includes the phosphorylation of the p38 mitogen-activated protein kinase that is observed following osmotic stress. Using specific blockade of this kinase, a dose-response inhibition of hyperosmolar NaCl-induced IL-8 synthesis was observed, similar to that in cells stimulated with IL-1. Thus, these studies suggest that IL-1 and osmotic shock utilize the same mitogen-activated protein kinase for signal transduction and IL-8 synthesis.

Balance of IL-1 receptor antagonist/IL-1 beta in rheumatoid synovium and its regulation by IL-4 and IL-10.

Abstract: The spontaneous production of IL-1 beta (IL-1 beta) and IL-1 receptor antagonist (IL-1Ra) by rheumatoid arthritis (RA) synovium, and the regulation of their production by IL-4 and IL-10, were studied. Supernatants from cultured synovium pieces from 19 RA patients were assayed for IL-1 beta and IL-1Ra production using ELISA and RIA, respectively. After 10 days of culture, spontaneous production of IL-1Ra was 1.42 +/- 0.43 ng/ml/100 mg of synovium whereas spontaneous production of IL-1 beta was 4.03 +/- 0.90 ng/ml/100 mg of synovium (n = 19). The addition of IL-4 reduced IL-1 beta production by 2.3-fold (p = 0.001) and increased that of IL-1Ra by 2.8-fold (p = 0.003). IL-10 had no significant effect on IL-1Ra production and suppressed IL-1 beta production (primarily in samples producing high levels of IL-1 beta). However, IL-10 was less potent than IL-4 in suppressing IL-1 beta production. IL-1Ra was mainly produced by rheumatoid synovial monocytes/macrophages. IL-4 was more potent than IL-10 in inducing IL-1Ra production by monocytes/macrophages purified from RA synovium, as well as from RA blood. Thus, RA synovium is characterized by an imbalance between IL-1Ra and IL-1 beta production, in favor of the latter. IL-4, and to a lesser extent IL-10, shift this balance in favor of an anti-inflammatory situation.

IL-6 and IL-8 production from cultured human endothelial cells stimulated by infection with Rickettsia conorii via a cell-associated IL-1 alpha-dependent pathway.

Abstract: Mediterranean spotted fever due to infection by Rickettsia conorii, is characterized by a general vasculitis. This vasculitis is thought to be due to a direct injury to endothelial cells induced by R. conorii. However, production and activity of cytokines on endothelial cells is an important pathway in inflammation, and part of the underlying mechanism of vasculitis. In the present studies, human umbilical vein endothelial cells (HUVEC) infected with R. conorii actively secrete high levels of IL-8 and IL-6 (P < 0.002, and P < 0.03, respectively, compared with uninfected cells). IL-1alpha, IL-1beta, or TNFalpha were not detected in the culture supernates. Nevertheless, IL-6 and IL-8 production was due, in a large part, to a cell-associated form of IL-1 alpha expressed on R. conorii-infected HUVEC, since production of these cytokines was suppressed by 80% (P = 0.0001) and 85% (P < 0.04) by the addition of IL-1 receptor antagonist, or anti-IL-1alpha antibodies (60% inhibition, P < 0.01 and 65% inhibition, P < 0.05, respectively) and IL-1alpha was measured after lysis of R. conorii-infected HUVEC but not in uninfected cells (P < 0.01). Rickettsial lipopolysaccharide does not seem to be involved, since polymyxin B did not reduce cytokine secretion. On the contrary, infection by intracellular R. conorii appears to be necessary to induce IL-1alpha and subsequently IL-8, since formalin-fixed R. conorii did not induce cytokine production. These observations demonstrate that R. conorii-infected HUVEC secrete IL-6 and IL-8 via the induction of cell-associated IL-1alpha, providing a possible mechanism for the vasculitis observed in Mediterranean spotted fever.

Abnormal vitamin B6 status in rheumatoid cachexia : association with spontaneous tumor necrosis factor α production and markers of inflammation

Abstract: Objective. To compare vitamin B6 levels in rheumatoid arthritis (RA) patients and healthy control subjects. Methods. We measured levels of vitamin B6 in 23 adults with well-controlled RA, and in 23 healthy control subjects matched for age, sex, race, and weight. Results. Although plasma folate and vitamin B12 concentrations and erythrocyte B6 activity coefficients were similar in the patients and controls, plasma levels of pyridoxal-5′-phosphate (PLP) were lower in the RA patient group (mean ± SD 46.1 ± 48.1 versus 69.3 ± 58.4 nmoles/liter; P ≤ 0.004). In multivariate analyses, PLP was inversely associated with tumor necrosis factor α (TNFα) production by peripheral blood mononuclear cells (PBMC) (P < 0.001), after adjustment for age, pain score, erythrocyte sedimentation rate, and use of nonsteroidal antiinflammatory drugs. Conclusion. PLP levels are reduced in patients with RA. This reduction is associated with TNFα production by PBMC.

Interleukin 1 induces HIV-1 expression in chronically infected U1 cells: blockade by interleukin 1 receptor antagonist and tumor necrosis factor binding protein type 1.

Abstract: Cytokines and cytokine antagonists modulate human immunodeficiency virus (HIV) replication in vitro and may be involved in HIV disease pathogenesis. An understanding of these cytokine networks may suggest novel treatment strategies for HIV-seropositive persons. U1 cells, a chronically infected promonocytic cell line, were stimulated with interleukin 1α (IL-1α), IL-1β or tumor necrosis factor (TNF) for 24 hr. The effects of these cytokines, and of anti-IL-1 receptor type 1 and type 2 (IL-1RI and II) antibody, IL-1 receptor antagonist (IL-1Ra), and recombinant human TNF binding protein type 1 (rhTBP-1, a form of TNF receptor p55), on HIV-1 replication, as measured by ELISA for HIV-1 p24 antigen, were determined. The effects of IL-1 and IL-1Ra on nuclear factor-κB (NF-κB) DNA binding activity, as measured by electrophoretic mobility shift assays, were also determined. IL-1α and IL-1β increased p24 antigen production in a concentration-dependent manner. IL-1Ra completely, and rhTBP-1 partially, suppressed IL-1-induced p24 antigen production. IL-1 increased NF-κB DNA binding activity and IL-1Ra blocked this effect. Since IL-1Ra blocks IL-1 from binding to both the IL-1RI and IL-1RII, monoclonal antibodies directed against each receptor were used to ascertain which IL-1R mediates IL-1-induced HIV-1 expression. Antibody to the IL-1RI reduced IL-1-induced p24 antigen production. Although anti-IL-1Rn antibody blocked the binding of 125IL-1-1α to U1 cells by 99%, this antibody did not affect IL-1-induced p24 antigen production. IL-1β enhanced TNFα-induced HIV expression when added before or simultaneously with TNFα. IL-1 induces HIV-1 expression (via the IL-1RI) and NF-κB activity in U1 cells. These effects are blocked by IL-1Ra and partially mediated by TNF. IL-1 enhances TNFα-induced HIV replication in U1 cells.

Circulating interleukin-1 receptor antagonist concentrations are increased in adult patients with thermal injury.

Abstract: OBJECTIVE To investigate the balance between circulating concentrations of interleukin (IL)-1 and its natural inhibitor interleukin-1 receptor antagonist (IL-1Ra) in human inflammation. DESIGN Prospective case-control study. SETTING University hospital burn care unit. PATIENTS Fifteen patients with second- or third-degree thermal injuries of 7% to 78% of total body surface and 15 healthy age- and sex-matched control subjects. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Median plasma IL-1Ra, but not IL-1 beta or tumor necrosis factor-alpha (TNF-alpha) concentrations were markedly increased on the day of admission in patients with thermal injuries compared with controls (1615 [range 426 to 23,800] vs. 494 [range 196 to 1093] pg/mL; p < .001). In survivors, the median IL-1Ra concentration normalized 12 to 21 days after admission. The concentration of IL-1Ra on the day of admission was weakly positively correlated to the extent and degree of thermal injury (r2 = .46; p < .05). IL-1Ra on days 1 to 3 was highest in three nonsurvivors with inhalation injuries compared with survivors (2166 [range 1362 to 36,624] vs. 1344 [range 665 to 13,085] pg/mL; p < .05). IL-1Ra increased significantly after debridement and skin transplantation (preoperatively 742 [range 488 to 1506] vs. postoperatively 1431 [range 1286 to 2107] pg/mL; p < .01). In nonsurvivors, median IL-1Ra was 3.6-fold higher than IL-1 beta on days 1 to 2 and 36-fold higher than IL-1 beta in three patients with bacteremia. IL-1Ra was studied for its relationship to previously reported parameters of the acute-phase response determined in the same samples from these patients. The increased concentrations of IL-1Ra coincided with a decrease in serum albumin concentration and increases in rectal temperature. However, IL-1Ra did not correlate with rectal temperature, plasma concentrations of endotoxin, IL-1 beta, or TNF-alpha either at admission or in follow-up samples. CONCLUSIONS Thermal injury causes an increase of circulating IL-1Ra, especially in patients with inhalation injuries. With the current plasma assays for IL-1 beta, IL-1Ra may be a more sensitive marker of human inflammation than IL-1 beta or TNF-alpha.

Rolipram, a specific type IV phosphodiesterase inhibitor, is a potent inhibitor of HIV-1 replication.

Abstract: Objective To determine the effects of rolipram, a specific type IV phosphodiesterase inhibitor, on tumor necrosis factor (TNF)-alpha production and HIV-1 replication. Design TNF-alpha enhances HIV-1 replication in vitro; blocking TNF-alpha and thereby inhibiting HIV-1 replication may therefore potentially delay progression of HIV disease. Pentoxifylline is a non-specific phosphodiesterase inhibitor that blocks TNF-alpha synthesis and HIV-1 replication in vitro and has been shown in preliminary clinical studies to decrease viral replication in HIV-1-infected patients. Rolipram, which selectively inhibits the predominant phosphodiesterase isoenzyme of monocytes, inhibits lipopolysaccharide (LPS)-induced TNF-alpha with 500-fold greater potency than pentoxifylline. We, therefore, hypothesized that rolipram would be a powerful inhibitor of HIV-1 replication. Methods The effects of rolipram and pentoxifylline on TNF-alpha production and HIV-1 replication were determined in infected and uninfected peripheral blood mononuclear cells (PBMC), in a chronically infected promonocytic cell line (U1) and in an acutely infected monocytic cell line (BT4A3.5). TNF-alpha was determined by specific radioimmunoassay and HIV-1 replication was measured by p24 antigen and HIV-1 mRNA production. Results Rolipram inhibited TNF-alpha production in LPS- and phorbol myristate acetate (PMA)-stimulated PBMC and in PMA-stimulated U1 cells. Rolipram also inhibited HIV-1 replication in the U1 cell line, as well as in acutely infected PBMC and BT4A3.5 cells. Depending on the experimental conditions, rolipram was 10-600 times more potent, on a molar basis, than pentoxifylline. Conclusion Rolipram is a potent inhibitor HIV-1 replication and therefore deserves further investigation as a potential therapeutic agent in the treatment of HIV-1-infected patients.

Coagulation of Whole Blood Stimulates Interleukin-1β Gene Expression

Abstract: To study interleukin (IL)-1 beta gene expression, reverse transcription-polymerase chain reaction was used on 25-microL whole blood samples from 11 healthy subjects. Coagulated and unclotted whole blood was compared. There was no evidence of IL-1 beta gene expression in any time zero samples (i.e., whole blood from which mRNA was immediately extracted) from 11 subjects, whereas a 388-bp band representing IL-1 beta mRNA was detected in all coagulated samples. No mRNA for IL-1 beta was detected in EDTA-anticoagulated whole blood, although in these samples the addition of lipopolysaccharide as a positive control induced the expression of IL-1 beta. In time course studies on samples allowed to clot, mRNA for IL-1 beta was detectable after 30 min. These findings demonstrate that IL-1 beta gene expression is not present in circulating cells of healthy subjects and that coagulation is a stimulus for IL-1 beta gene expression. This may be a mechanism by which thrombosis produces inflammation and fever.

Human vascular smooth muscle cells produce an intracellular form of interleukin-1 receptor antagonist

Abstract: Interleukin-1 (IL-1) is a proinflammatory monocyte- and macrophage-derived cytokine that has potent vasorelaxant effects on vascular smooth muscle cells (VSMC). VSMC themselves also express both IL-1 alpha- and beta-genes, suggesting that IL-1 may be an autocrine regulator of VSMC function. The present study demonstrates that human saphenous vein VSMC (HSVSMC) produce IL-1 receptor antagonist (IL-1Ra), a specific inhibitor of IL-1 action. IL-1Ra was produced constitutively in most experiments, and its production was upregulated by phorbol 12-myristate 13-acetate and by IL-1 beta. IL-1Ra produced by HSVSMC remained predominately cell associated and was not detectable extracellularly. Furthermore, reverse transcription-polymerase chain reaction analysis and cDNA sequencing indicated that HSVSMC express the alternatively spliced form of IL-1Ra which lacks the signal peptide present in secreted IL-1Ra. HSVSMC also produced IL-1 alpha and the precursor form but not the mature form of IL-1 beta. These results suggest that HSVSMC lack active IL-1 beta-converting enzyme. Like IL-1Ra, IL-1 beta precursor and IL-1 alpha remained cell associated, predominately in the cytosolic fraction. IL-1 beta induced production of both IL-1Ra and IL-1 alpha at each time point and concentration tested. In contrast, platelet-derived growth factor and transforming growth factor-beta augmented production of IL-1Ra, but not that of IL-1 alpha. These results are suggestive of an autocrine role for cell-associated IL-1Ra, as well as for IL-1 alpha and IL-1 beta, in the regulation of VSMC function.

Modulation of Acute Myeloblastic Leukemia (AML) Cell Proliferation and Blast Colony Formation by Antisense Oligomer for IL-1 Beta Converting Enzyme (ICE) and IL-1 Receptor Antagonist (IL-1ra)

Abstract: Peritoneal dialysis is in widespread use for the treatment of chronic renal failure. Infection is still one of the major complications and can include peritonitis and pericannular problems. The rate of peritonitis is currently 0.5 episodes per patient year with disconnect systems, and there are about 0.4 exit-site infections (ESIs) per patient year. ESI is associated with a high rate of catheter removal and replacement. Staphylococcus aureus is a common cause of peritonitis and accounts for more than half of all ESIs. Nasal carriage of S. aureus is associated with a much higher rate of ESI. Treatment of ESIs is unsatisfactory. The type of exit-site care, however, does influence the rate of infection and prophylaxis with oral rifampicin and local or nasal mupirocin has been claimed to reduce ESIs. A large multicentre double-blind trial of nasal mupirocin has just been completed and preliminary results show a reduction in the incidence of S. aureus-induced ESI. The cost benefits of such a regimen are being evaluated.

Glycosylated recombinant human tumor necrosis factor binding protein-1 reduces mortality, shock, and production of tumor necrosis factor in rabbit Escherichia coli sepsis.

Abstract: ObjectiveTo examine the effect of glycosylated recombinant human tumor necrosis factor binding protein-1 (r-hTNF binding protein-1), the extracellular domain of the tumor necrosis factor receptor p55 produced in mammalian cells, in a rabbit model of circulatory shock due to Escherichia coli.DesignPr

Interleukin-10 enhances human immunodeficiency virus type 1 expression in a chronically infected promonocytic cell line (U1) by a tumor necrosis factor alpha-independent mechanism.

Abstract: TNF-alpha enhances HIV-1 replication in acutely and chronically infected cells and likely contributes to the wasting associated with the acquired immunodeficiency syndrome. Agents that inhibit TNF-alpha activity should theoretically delay the progression of disease, and several are currently in clinical trials. We hypothesized that IL-10, a cytokine that suppresses the gene expression and synthesis of TNF-alpha in monocytic cells, might inhibit HIV-1 replication. As expected, IL-10 suppressed PMA-induced TNF-alpha production in U1 cells; however, when U1 cells were cultured in the presence of PMA and increasing doses of IL-10, a dose-dependent increase in HIV-1 expression was observed. IL-10 also enhanced IL-1 beta-, TNF-alpha-, and GM-CSF-induced HIV-1 expression in U1 cells, and this occurred, at least in part, at the level of transcription. We next stimulated cells under conditions of TNF-alpha blockade. When PMA-induced TNF-alpha activity and HIV-1 replication were blocked by the presence of soluble TNF receptors, IL-10 independently enhanced HIV-1 replication. In contrast, other agents that are capable of blocking TNF-alpha synthesis or TNF-alpha activity either had no effect (IL-13 and IL-4) or inhibited HIV-1 expression (soluble TNF receptors and pentoxifylline) in U1 cells. These data suggest that IL-10, while inhibiting TNF-alpha synthesis, has an independent mechanism of action that enhances HIV-1 replication. Therefore, IL-10 may have undesirable effects in HIV-1-infected patients.

Biologically active fragments of IL-1β

Abstract: The subject invention concerns a nucleic acid comprising a nucleotide sequence encoding human interleukin-1 (IL-1), and fragments thereof, and the polypeptides and peptides obtained. Specifically, the subject invention comprises the cloning of a cDNA synthesized by reverse transcription of poly(A)RNA isolated from adherent human monocytes stimulated with bacterial endotoxin. Human IL-1 is useful to induce the production of IL-2 by activated T-cells; it also acts on B-cells and NK-cells. The subject invention further concerns antibodies that are immunoreactive with human IL-1β proteins.

Blocking interleukin-1 in sepsis

Abstract: Interleukin-1 (IL-1) is a polypeptide which possesses a broad spectrum of biological activities, many of which are associated with disease. It has been studied for its ability to induce fever, sleep and anorexia, elevate prostaglandins and nitric oxide, stimulate the release of pituitary hormones, elevate hepatic acute phase proteins, increase gene expression for other cytokines and augment the proliferation of T and B lymphocytes. In addition, IL-1 increases the synthesis of collagenases and decreases the synthesis of proteoglycans, resulting in joint destruction. More recently, IL-1 has been shown to induce hypotension and upregulate endothelial cell adhesion molecules, both important parameters of the septic shock syndrome. IL-1 also possesses host defense properties. For example, pretreatment with IL-1 non-specifically reduces lethality to bacterial and fungal infections, even in the absence of circulating neutrophils. IL-1 has been given to humans in clinical trials; as increasing doses are given, IL...